Tuesday, December 27, 2005

Surveillance: What Bush Should Have Done

Should all international communications be scanned by the NSA? Possibly, but not without warrants and accountability.

President Bush should have established automated mechanisms to scan messages for content, but he should also have created safeguards against use of the information by humans, and obtained the consent of Congress (which was in Republican hands, by the way).

What kinds of safeguards might be appropriate? Well, human translators might be permitted to analyze flagged messages, but they would only have access to the identities of the participants under court order. Also, the collected information should only be available for use in counterterrorism cases. Otherwise, this technology will be abused by people on fishing expeditions.

As it stands, Bush broke the law by illegally wiretapping communications. He wants us to trust him after all his lies. Trust him? Let's see, how did Bush put it? "Fool me once, shame on — shame on you. Fool me — you can't get fooled again."

I think there are even odds that Bush will be impeached if the Democrats take back Congress in 2006.

Thursday, December 22, 2005

Intelligent Design: The story so far

I've been debating ID online for the last couple of months. These are my conclusions so far.

The ID Claims
Some of the ID folks I have debated accept most of mainstream evolutionary science. Some even accept macroevolution, i.e., the idea that speciation is explained by natural selection and mutation. What they generally don't accept is that the pool of genes that is responsible for even the most primitive life could have evolved using undirected mechanistic processes. Instead, the sharper IDists focus on "front loading" - the idea that a designer programmed all the original genes, and mechanistic evolution took over from there. They're basically saying that a designer built all of the lego blocks, and natural processes built stuff out of those blocks.

Needless to say, they don't want to talk about the designer, who is presumed to be God. However, the term "supernatural explanation" is an oxymoron. The supernatural is a name we give to the unexplainable. Invoking the supernatural gives you a well-deserved one-way ticket out of the scientific enterprise. So ID proponents aim to find some scientific signature of design, but without reference to the nature of the designer.

To this end, IDists have tried to cook up some measures of whether or not a system is designed. The first measure is something called irreducible complexity (IC). A system is IC if it does not function if any one of its multiple parts is removed. For example, the blood-clotting mechanism in humans may fail if any one of certain proteins are not present. IDists argue that IC systems could not have evolved (at least not with high probability) because a system with multiple components could not have evolved incrementally, but would have to have evolved all at once.

As defined, IC systems do exist. However, the conclusion that they could not have evolved has been soundly refuted. For the ID claim to be valid, they have to show that none of the components of the IC system could have had any selective advantage outside the IC system itself. If a protein used in blood-clotting has no possible use outside the clotting mechanism, then ID has a more compelling case. However, if that protein has any other benefits to a life form, then evolution will have replicated the genes for making that protein anyway. It doesn't even matter whether life still has an alternative need for that protein. Though the protein may no longer be needed for anything except blood-clotting, as long as it was once useful for something, evolution has no trouble accounting for it.

The other idea that ID proponents refer to is something called complex specified information or CSI (yes, it's named after the TV show). CSI is very poorly defined. The concept has no credibility among mathematicians and scientists. ID advocate William Dembski has tried to cook up a formula for calculating CSI, but it has been solidly refuted. Dembski has claimed that information cannot be created through unguided mechanistic processes, but this is clearly false. Genetic computer algorithms do this every day by computing solutions to complicated problems.

Design as Science
Certainly, there are situations in which design is a scientific hypothesis. In archaeology and criminal investigations we regularly pursue design hypotheses. However, in these cases, we also know through direct experimental test that intelligent entities are present and available to do the designing.

What about cases where we have no other evidence of intelligence? The search for extraterrestrial intelligence (SETI) is a case in which we hope to detect intelligence in transmissions without otherwise observing the intelligent aliens. If we see a narrowband transmission containing a repeating sequence prime numbers, we're likely to think that it originated from an intelligent source. There are two things that would tip us off to the intelligence behind such a message. The first is artificiality - the signal is unlike anything predicted by alternative natural causes. The second is utility - narrowband transmissions containing mathematical data have utility to an intelligence.

Artificiality
Artificiality is sometimes easy to detect. If you find a intricate, mathematically precise structure made of a bulk material (like a titanium alloy), then this is a good signature of life, if not intelligence. Bulk materials like metals can easily be studied in the lab, and we can generally test the material to see that it doesn't spontaneously form such structures over a range of different formation conditions.

Yet, the artificiality of a structure is extremely difficult to detect when we don't have the knowledge or skillset to be able to synthesize a comparable structure in the lab. This is the case with the nanomachinery of living cells. Today, we have neither the knowledge nor the technology to fabricate an artificial amoeba. So, we don't understand the dynamics of cell structure formation or abiogenesis. For this reason, we cannot point to biological structures and say they are artificial because they are not expected under the laws of biochemistry. For all we know, such structures might have formed easily in Earth's primordial soup.

You can't claim the artificiality of a structure when you don't have detailed knowledge of the physics involved in its history.

Utility
Utility is a more compelling signal of design. Let's revisit our SETI example. Narrowband signals are harder to generate, but they use a lot less power, and power efficiency is useful. Also, a sequence of transmitted primes has utility as a universal greeting message for alien civilizations.

The same applies for the common examples of intelligent design by humans. For example, we can observe that a flint axe has utility to a creature that has limited intrinsic ability to cut flesh and bone.

Consider a simple steel girder. Such a girder has utility in construction. In fact, any collection of regularly shaped macroscopic objects will typically have a utility. We manufacture things in regular sizes so that we can apply rule-based procedures to them in their application or for commerce.

Language symbols also have utility for storing information. Even if we could not translate the text in a message, we might be able to perceive some utility to its design.

Now, evolution also predicts we will find structures that have utility. The one utility evolution predicts is survival. Evolutionary processes will generate structures that have selective advantages, i.e., that make their biological hosts fitter in their respective environments. So, if you're looking for signs of ID in biological life, you need to look for structures that have utility, but which have no survival benefit (neither for the species in question, nor for its ancestors).

So, if you look at a biological structure, e.g., the human eye, you cannot argue that its utility is enough to infer ID unless you can show that the human eye has no selective advantage (which, clearly it does have).

One problem for ID proponents who favor early-stage design (as opposed to ongoing intelligent tampering) is that sexual reproduction, mutation and natural selection will probably have pruned from ancestral life any feature which had no selective advantage. If an alien seeded Earth's life with programmed DNA, any part of that program that wasn't related to the system's survival would likely have been eliminated by natural evolutionary processes.

Prediction
When challenging ID proponents to make predictions, they commonly respond by saying that unguided evolution (UE) makes no predictions. IDists are making two mistakes when they do this. The first is in assuming that ID and UE are theories. They are not theories per se. They are classes of theories. A theory that aims to explain a facet of evolution using specific unguided mechanistic processes would be categorized as a UE theory. A theory that proposed that a biological system was designed for a particular utility by a particular designer using some specified technique would be a theory that falls into the ID category.

UE contains many predictive theories. UE theories predict inherited mutations, varying rates of speciation, patterns of adaptation, etc. UE theories are statistical. They cannot predict exactly what evolution will produce, only that it will produce something with statistical, selective advantage in its environment. UE is predictive because it contains theories that are predictive.

ID fails to be predictive because there are no scientific theories that fall into the ID category. In an effort to bypass the question of God, IDists ignore the question of utility. A discussion of utility would force them to speak about the utility of life beyond mere survival. Unless you know something about the designer, you cannot say what would be useful to him/her/it/them. This forces them to consider artificiality alone, and to hopelessly do so in a realm where the physics are poorly understood.

A Word About Probability
You'll hear ID proponents talk about the low probabilities that life formed by undirected mechanistic processes. Most of this handwaving is pure bantha poodu. I once saw a presentation in which the speaker spoke of the astronomical odds against a DNA molecule forming out of its constituent atoms in a vacuum! What does this have to do with evolution? Nothing. It just generates irrelevant numbers to throw at non-expert audiences. No one thinks that life formed by individual atoms flying together all at once. Atoms would have formed into precursors like amino acids, proteins, and membranes. More complex molecules would have formed from the precursors. Little research has been done in this area, so no one knows the odds of life forming in a planet-sized bath of such precursors. It could be unlikely, or it might be a virtual certainty. We don't know.

However, even if we did know that the formation of life is improbable under those conditions, one cannot use this as an argument for design. We are not independent observers of the creation of life on this planet. We are dependent observers. We are not free to observe life not forming on Earth 3.8 billion years ago. That is, the probability that life formed on Earth and led to our existence is unity.

This scenario is very different from us, say, observing that new life developed independently on another planet. In that case, our existence as observers does not depend on the formation of life on this other world. If we see life improbably popping up elsewhere, then we have a clue that we don't understand what's happening in abiogenesis.

This question of observer independence is closely related to the Doomsday Argument and the Adam and Eve Paradox. If you try to apply probability measures when you're not an independent observer, you run into all sorts of nasty paradoxes.

By the way, sound reasoning about probability reveals that there is no cosmological fine-tuning problem, either.

Conclusion
There are two scientific signatures for design: artificiality and utility.

Our ability to detect artificiality is limited by gaps in our knowledge of natural phenomena in biochemistry. Today, ID relies on these gaps in our knowledge of natural processes to suggest that artificiality lurks within biology.

The only utility we have observed in life so far is selective advantage. This is exactly what we would expect of life that was created through unguided evolutionary processes. As far as I can tell, there are no ID predictions about utility because God has no scientific utility for life.

No trace of ID has been found by either method. No experiment has been proposed to test an theory of ID because there are no actual theories of ID.

The frequent misbehavior of ID proponents cited by the Judge in the Dover case has raised the bar even higher for ID theories. ID theories (if we ever see any) will require extraordinary evidence in order to overcome the noise of all the false claims floating around in ID-land.

Where's the Outrage?

...asks Arlene Getz at Newsweek.com:
Tutu recalled teaching in Jacksonville, Fla., when Bush won re-election in 2004. "I was shocked," he said, "because I had naively believed all these many years that Americans genuinely believed in freedom of speech. [But I] discovered there that when you made an utterance that was remotely contrary to what the White House was saying, then they attacked you. For a South African the deja  vu was frightening. They behaved exactly the same way that used to happen here - vilifying those who are putting forward a slightly different view." Tutu made these comments to me exactly a year ago next week. I haven't seen any reaction from him about the latest eavesdropping revelations, but I doubt he is remotely surprised at the U.S. president's response: a defense of the tactic, together with a warning that the government would launch an investigation to find out who leaked the news to The New York Times.
For most of my life, I've been a trusting sort of chap. I really want to be able to give the government the benefit of the doubt when they say they'll spy on us with care.

However, Bush is asking us to trust him. And no one should. This is a man who has called the Constitution of the United States "a goddamned piece of paper." A man who has trashed international treaties and abandoned the Geneva conventions. He has explicitly championed torture. He's given the Pentagon the job of the State Department, and allowed the military to do domestic investigation of civilians.

Some will say that he's really pulling out the stops in an effort to protect America. They would be wrong. What about border control? Our southern border is totally porous. This makes no sense. His foolish attack on Iraq has weakened us militarily and diplomatically, and made terrorism far, far worse. Thanks to Bush, thousands of new terrorists have become trained veterans of urban warfare. The man is thoroughly incompetent, to say the least.

Ask yourself this question. Why does Bush need to illegally spy on Americans without a warrant when there is already a secret court designed to facilitate legitimate national security needs?
The 11-member Foreign Intelligence Surveillance Court is perhaps the most secretive in America, created by the Foreign Intelligence Surveillance Act (FISA). It reviews U.S. government requests for surreptitious eavesdropping to gather intelligence on potential U.S. enemies. Last year, according to a report to Congress, it received 1,758 warrant requests -- and approved all but four.
Bush has consistently tried to remove transparency and accountability from government. Here is yet another case where he asks Americans to trust him instead of trusting institutions.

Five years ago, the United States was the leader of the free world. The USA stood for freedom, human rights, technological innovation and liberal democracy. Now, we stand for spying, torture, imprisonment without due process, invasion without due cause, breaking treaties, fundamentalism, and incompetence. What's next? When do you say enough is enough? Is there any outrage that Americans will not tolerate?

Oh yeah. Consensual sex in the oval office.

Tuesday, December 20, 2005

I propose a toast!

To science!

The Intelligent Design movement suffered a major setback today. Not only did they lose the Dover, PA trial, they got a shellacking.

PZ Meyers over at Pharyngula has all the juicy details, including these quotes from the court's opinion:

Moreover, cross-examination revealed that Professor Behe's redefinition of the blood-clotting system was likely designed to avoid peer- reviewed scientific evidence that falsifies his argument, as it was not a scientifically warranted redefinition.
...
We therefore find that Professor Behe's claim for irreducible complexity has been refuted in peer-reviewed research papers and has been rejected by the scientific community at large.
ID is a politico-religious movement that aims to undermine the scientific enterprise by redefining it to incorporate the supernatural. That's basically what the judge said:
In his ruling, Jones said that while intelligent design, or ID, arguments “may be true, a proposition on which the court takes no position, ID is not science.” Among other things, he said intelligent design “violates the centuries-old ground rules of science by invoking and permitting supernatural causation”; it relies on “flawed and illogical” arguments; and its attacks on evolution “have been refuted by the scientific community.”
It's about time someone put a stop to their unpleasant scheme.

This evening, I'm going out to celebrate.

Wednesday, December 14, 2005

Inference and Bayes' Theorem

Say you want to calculate the probability that your theory T is correct given observations O. According to Bayes' Theorem, the probability of T given O is

P(T|O) = P(O|T) P(T) / P(O)

where P(O|T) is the probability of O given T, and P(T) is the prior probability of T without accounting for observations O. P(O) is the prior probability of O.

P(O|T) is the degree to which T predicts O. If T doesn't predict O then either (i) T predicts that O is unlikely/impossible, or (ii) T is uncorrelated with O.

Let's consider case (ii) where T is consistent with O but doesn't preferentially predict O.

If T is consistent but uncorrelated with O, then the probability of O given T is just the probability of O. That is P(O|T) = P(O). Consequently, P(T|O) = P(T). In this case, you cannot make any inference of T from O.

More intuitively, the probability that a theory T is inferred by observations O is proportional to the force with which T predicts O. If T doesn't preferentially predict O, you are not justified in making an inference from O to T.

For an Intelligent Design theory to be inferred from the data, it must be specific enough to predict something about the observations.

One objection to this conclusion would be to claim that an arbitrary T can always be fitted to O such that it preferentially predicts O. For example, one might claim that "T is the generic theory that there is an unknown agent that is responsible for O." However, the problem here is that T is no longer an inference from O. It is a paraphrasing of O. (After all, we originally set out to answer the question "what is the unknown agent responsible for O?")

So, how do we know whether or not T is just paraphrasing O? We can know this by counting parameters. If we have N data points, we need N parameters to paraphrase the data without making any inferences. For example, we can always write the next number in a sequence as the sum of the previous number and some parameter tuned to give us the correct answer.

Therefore, an inference is a theory T with fewer parameters in it than O. Since there are fewer parameters in T than in O, some proper subset of O must be predicted by T from the remainder of the data in O.

Generic ID makes no predictions, not even within the existing data we have. It has more free parameters than any amount of data we throw at it. It is, at best, a paraphrasing of the data.

We can certainly infer the action of intelligent agency from some data sets, but only when our intelligent agent theory is predictive in some way.

Monday, December 12, 2005

More on Inference and Explanation

Suppose my car won't start. Is there an acceptable explanation which explains how the car fails to start that does not also predict that the car will not start?

For example, I would predict that, if the fuel line were cut, the engine would not start. So, a cut fuel line sounds like an explanation, whether it is probable or not.

However, I cannot accept that my car will not start because "roses are red." Roses are indeed red, and their redness is perfectly consistent with my car not starting. However, the redness of roses does not predict that my car won't start.

Nor would I accept the "explanation" that an undetectable gremlin prevented the engine from starting. The undetectability of gremlins (and their unpredictable nature) renders the gremlin just another word for "ignorance of cause."

So, a plausible explanation is a picture of a cause and effect relationship. If the proposed cause is unknowable, or does not predict the effect, then you don't have an explanation.

Therefore, any valid explanation of a phenomenon must predict that phenomenon from knowable facts (i.e., from chemistry, physics, etc.).

To claim that there is no physical theory that explains a physical phenomenon is to claim that there is no explanation of that phenomenon at all.

Saturday, December 10, 2005

Pegasus Exists

I apologize for the length of the following brain dump. Writing is my way of forcing myself to think these things through.

Unlike The Golden Age of Balloning, there no fees or penalties imposed for not reading this post.

Radical Empiricism
I have really taken an interest in Radical Empiricism. I'm not buying into the philosophy of William James wholesale. Instead, I merely claim that thought and emotion are experienced, and should be accorded a more equal footing with the physical experiences of taste, touch, sight, sound and smell.

Suppose we redefine the term empirical to refer to any pattern which is experienced, i.e., not just patterns among the five senses. This radical empiricism asserts that all the things we think and feel are also empirical because we experience them. So, the very idea of, say, "Pegasus", commits us to its existence, at least among mental sensations.

Of course, in common use, we don't normally say that purely mental things "exist." So what is the connection between existence in this radical empiricism and existence in the everyday sense? It is clear that the more familiar use of the verb "to exist" signifies a correlation between a mental pattern and a physical one. Thus, in common use, claiming that "Pegasus exists" is the same as asserting that one can experience patterns in the five physical senses that correlate with the mental pattern of Pegasus.

The correlations between patterns of mental sensation and patterns of physical sensation need not be direct. Finding feathers with equine DNA would qualify as an indirect correlation between the mental and physical patterns that would be Pegasus.

Philosophical Existence
Philosophically, the question of existence gets more complex. The world of sensation appears to us "as if" there is an external world that impresses upon our senses.

In the scientific world, existence still retains the same meaning as it does in everyday use, namely, as a correlation between mental sensations and physical ones. This is why it is perfectly valid under radical empiricism to formulate a theory of quarks that explains the experimental data, even though quarks are not observable. Quarks themselves exist as mental patterns that correlate indirectly with physical observations.

Though we are permitted to ask whether mental patterns have corresponding physical patterns, we cannot ask whether there is a correlation between mental patterns and things that, even in principle, cannot imprint upon our senses. The question is simply malformed because there is nothing to correlate the thoughts with. Neither the verb "to exist" nor the noun "thing" has any meaning beyond experience or potential experience.

From this perspective, a multitude of metaphysical problems are just a result of misclassifying thought as something beyond experience, a classification which seems, at best, an artificial distinction among experienced things.

Consider platonism. Here's how the Stanford Encyclopedia of Philosophy briefly defines it:
Platonism is the view that there exist such things as abstract objects - where an abstract object is an object that is wholly non-spatial and non-temporal (i.e., that doesn't exist in space or time) and, hence, is entirely non-physical and non-mental.
Are platonists claiming the existence of things not experienced? If so, they would be taking language far beyond its realm of applicability.

Philosophical Inferences
How precisely can we state the limitations of knowledge given that our only window on the world is an empirical one? Historically, we have been very successful in identifying patterns in the world of physical sensation that are well-explained by structures that exist only in mental models (e.g., the aforementioned quarks). We have also been able to do the reverse. We have correlated physical observations with patterns of mental sensation using lie detectors or functional Magnetic Resonance Imaging.

What is not so obvious is whether it is possible to infer information from sensation that is wholly non-empirical. I claim that such inferences are impossible.

If I have a set of propositions P = {P1, P2, P3, ...}, I can only make an inference, N, from these propositions if N has some implications for the truth of my set of propositions P. That is, knowing N and some subset of P, I can derive the remainder of P.

Therefore, any inference I make from a set of sensations must have implications for that set of sensations. This rules out any possibility of inferring anything non-empirical from empirical facts.

Furthermore, when we say that a mental conception is "about something," we're saying that the conception correlates with some other sensation, mental or physical. This raises doubt about whether non-empirical propositions are really about anything at all.

What Doesn't Exist
The non-existence of a thing is the absence of a sensation that correlates with a mental conception. There are mental and physical things that don't exist. Prime numbers between 7 and 11 would be an example of a mental sensation that does not appear to exist. However, we can only say that we have searched for a thing and found nothing, not that there is no possibility that such a thing will be found. We can have very high confidence that certain patterns (especially some mathematical ones) will not be found to exist, but I have proposed no mechanism to guarantee certainty of non-existence.

Science, Physical and Mental
If there are well-defined patterns in sensation, what are the properties of such patterns, and how can we find them?

We perceive correlations in sensation. We can see a man on horseback, water under a bridge, water flowing downstream, and apples falling from trees. We can see the patterns of arithmetic in collections of objects, and the simultaneous presence of two sensations.

We can also correlate the correlations themselves. We can correlate the man on horseback riding across a bridge under which water flows downstream. What we don't see is a correlation of correlations that denies one of the correlated sensations. We don't simultaneously correlate the pattern of the man on horseback riding across a bridge under which water flows downstream with the pettern of the same horse with no rider.

There is a name for this latter kind of correlation: an inconsistent correlation. Not only do we perceive the world to be largely consistent, we have little use for inconsistent information. Any action that is inconsistently correlated with the experience of something desirable, might just as frequently produce the experience of something unpleasant. It would be fair to say that an action that has an inconsistent correlation with a particular outcome is not truly correlated with that outcome at all.

Logic is the procedure used for detecting inconsistencies in correlations. By correlating sensations with symbols, we can implement the rules of logic more formally as symbolic logic.

If there are useful correlations to be found in sensation, they must obey the rules of logic. The search for useful correlations is a search through all of the logically consistent mental patterns that can be correlated with observations. That is we are looking for a mental pattern that acts as a model of the world, so that our observations appear as if the world fits the model. This is why mathematics is important. Not only are mathematical structures empirical themselves, they also represent an enumeration of logically consistent models that can be correlated with a logically consistent physical world.

From here, it is easy to see why the scientific method works. We locate a logically consistent mathematical structure that can be correlated with our observations of the world, then we use that same structure to predict future observations and correlations. If the prediction turns out to be wrong, we modify the mathematical model and try again.

There is a very important empirical fact about mathematics that has implications for this analysis. Given a finite number of experiences and correlations, there are an infinite number of mathematical models that can be correlated with those experiences. If I provide you with some points on a graph, you can fit a curve to those points, but you cannot be certain that you have correctly fitted your curve to all the points that might appear on the graph in the future.

Meaning
What implications does radical empiricism have for meaning in language? Given the experience of a language proposition, we can only interpret it by correlating it with other experiences. This means that meaning in language is a scientific endeavor. No language proposition has infinite precision in its meaning because no correlation confers infinite precision. Instead, we form a scientific theory about the meaning of the proposition that has implications for how we expect to see the proposition used (correlated) in the future. That is, to have meaning, a proposition must be correlated reliably with something other than the symbolic sense data in which it is written. The meaningful proposition must claim definite implications, if it is true versus if it is false.

The extent of the implications of a proposition map out the domain of its meaning. If a proposition has implications only within a related set of propositions about mental sensations, then the proposition's meaning does not extend to physical patterns. The propositions of algebra do not, by themselves, have meaning that extends to the physical world. All propositions are evaluated within a specified context. This allows a proposition and its negation to be true in two different contexts without contradiction. The separation of contexts is what eliminates the simultaneous truth of the propositions from rendering the system inconsistent. Note that context boundaries may not be on sense boundaries. Two purely mental contexts may be totally independent, e.g., two algebra problems can exist without contradiction in their respective contexts, despite having axioms that would conflict if they were in the same context.

A scientific theory combines the propositions of mathematics with the empirical propositions of physical experience. The theory creates a new context in which the mathematical propositions have implications for the physical ones. This merged context is created by rules of correspondence between mental and physical sensations. In such a system, physical sensations are added to the system as new axioms. If the new empirical axioms render the system inconsistent, then the theory is disproved. If the new empirical axioms are consistent, then the theory is confirmed.

In contrast, a metaphysical system is one in which propositions about mental sensations are declared to have no implication for physical sensation. This is a denial that the metaphysical propositions share context with the physical world. However, creating this kind of separation is no different from the establishment of a mathematical context. Thus, at best, metaphysics is no different from mathematics, save for the evocative symbols it uses.

Friday, December 09, 2005

Inference

Consider the numeric sequence:

1, 2, 3, 5, 7, 11, ?, ?, ?,...

There are an infinite number of formulas that could generate this sequence.

Consider these conjectures:
1) The sequence is generated by an unknown formula that produces {1, 2, 3, 5, 7, 11} and follows it with indeterminate numbers.

2) The sequence is generated by a formula that produces {1, 2, 3, 5, 7, 11} and follows it with the sequence {6, 3, 2, 6,...}.

3) The sequence is an ascending list of integers evenly divisible only by themselves and 1.

The list of such consistent conjectures is infinite. Which ones do you infer?

I can see three criteria that we might apply to determine whether or not an inference is valid:

(A) A conjecture is inferred if it merely replicates the data, i.e., it is consistent with the data.

(B) A conjecture is inferred if it replicates some subset of the data, and makes a prediction about the future.

(C) A conjecture is inferred if it replicates some subset of the existing data from another subset of the existing data, i.e., it internally predicts the data.
If you go with criterion (A), then every data set should lead you to infer a solution like #1. But #1 isn't explanatory. You don't know anything more about the data (or the future) if you accept solution #1.

Solution #2 has the added virtue that it is predictive. However, it has more free parameters than the data set. You have no more reason to infer this theory instead of a different theory that will predict any other number as the next number in the series. This solution could be inferred by criterion (B).

Solution #3 meets criterion (C). You have reason to choose solution #3 based only on the data in the existing set. Any number in the sequence predicts the next and previous number in the sequence.

To summarize the criteria met by these solutions:




Criterion ACriterion BCriterion C
Solution 1YesNoNo
Solution 2YesYesNo
Solution 3YesYesYes


I claim:

i) that all three solutions are consistent, but not all are inferred, unless inference means the same thing as consistency. I reject criterion A.

ii) that a solution must be future-predictive to be scientific, but that future prediction alone is not adequate for inference. I reject criterion B.

iii) solutions that are internally predictive are inferred. Your inference should enable you to predict some subset of your data from another subset of your data. I accept criterion C.

This issue of inference came up in a recent discussion about Intelligent Design. My claim is that generic ID doesn't make any predictions, either internally or externally. Therefore, it's not even inferred, let alone scientific. However, if your ID theory is specific enough to allow you to predict, say, one aspect of the fossil record from another aspect, then you can make an inference. Your inference may be less than scientific, but it is, at least, an inference. To do this, you have to know enough about the physical limitations of the designer to say why the data is the way it is.

The next question is, are there any explanations that meet criterion B, but not C?

I'm guessing there aren't because any such solution wouldn't explain the existing data set. It would just be a wild guess about the future.

Tuesday, December 06, 2005

The 2004 Torture Referendum

A recent poll finds that sixty-one percent of Americans approve of torture. In 2004, I echoed the sentiment that the American people had a simple choice in the November presidential election. That choice was to vote for or against Abu Ghraib. At the time, I thought it a clever rhetorical device. It's now abundantly clear why this device failed to have much persuasive effect on my fellow citizens. They did vote on the torture issue, but in favor of George W. Bush.

Monday, December 05, 2005

Everything is Empirical

Yesterday, I found David Hume's book, An Enquiry Concerning Human Understanding at Project Gutenberg.

Published posthumously in 1777, the text remains lucid:
Every one will readily allow, that there is a considerable difference between the perceptions of the mind, when a man feels the pain of excessive heat, or the pleasure of moderate warmth, and when he afterwards recalls to his memory this sensation, or anticipates it by his imagination. These faculties may mimic or copy the perceptions of the senses; but they never can entirely reach the force and vivacity of the original sentiment. The utmost we say of them, even when they operate with greatest vigour, is, that they represent their object in so lively a manner, that we could almost say we feel or see it: But, except the mind be disordered by disease or madness, they never can arrive at such a pitch of vivacity, as to render these perceptions altogether undistinguishable. All the colours of poetry, however splendid, can never paint natural objects in such a manner as to make the description be taken for a real landskip. The most lively thought is still inferior to the dullest sensation. - Paragraph 11
It is common in everyday speech to separate the empirical (the things we experience in the world of the five senses), from the rational (the things that happen inside our minds). But isn't it better to consider every aspect of experience as constituting empirical fact?

If so, thought and imagination should also be considered empirical. We make discoveries in our minds by way of reason and explanation, and we remember our thoughts much the way we remember a day at the beach.

Breaking down the artificial separation between the rational and the empirical is liberating. As Hume explains above, our liberation costs us nothing in our ability to distinguish imaginary things from physical things.

However, we must surrender absolute certainty in making our escape:
There is a species of scepticism, antecedent to all study and philosophy, which is much inculcated by Des Cartes and others, as a sovereign preservative against error and precipitate judgement. It recommends an universal doubt, not only of all our former opinions and principles, but also of our very faculties; of whose veracity, say they, we must assure ourselves, by a chain of reasoning, deduced from some original principle, which cannot possibly be fallacious or deceitful. But neither is there any such original principle, which has a prerogative above others, that are self-evident and convincing: or if there were, could we advance a step beyond it, but by the use of those very faculties, of which we are supposed to be already diffident. The Cartesian doubt, therefore, were it ever possible to be attained by any human creature (as it plainly is not) would be entirely incurable; and no reasoning could ever bring us to a state of assurance and conviction upon any subject. - Paragraph 116
[Hmmm. Perhaps it is time to change my blog subtitle!]

Hume's skepticism does not deprive us of logic, mathematics, science or meaning. Hume's philosophy is infused with practicality. It merely admits that all conclusions we might reach in these endeavors have some degree of uncertainty. With diligence and repetition, the uncertainties of constructions like logic, mathematics and meaning can be made arbitrarily small.

Saturday, December 03, 2005

Historians: Bush Worst President Ever

An informal survey of historians suggests George W. Bush will be remembered as the worst president in U.S. history.

  • He has taken the country into an unwinnable war and alienated friend and foe alike in the process;

  • He is bankrupting the country with a combination of aggressive military spending and reduced taxation of the rich;

  • He has deliberately and dangerously attacked separation of church and state;

  • He has repeatedly "misled," to use a kind word, the American people on affairs domestic and foreign;

  • He has proved to be incompetent in affairs domestic (New Orleans) and foreign (Iraq and the battle against al-Qaida);

  • He has sacrificed American employment (including the toleration of pension and benefit elimination) to increase overall productivity;

  • He is ignorantly hostile to science and technological progress;

  • He has tolerated or ignored one of the republic's oldest problems, corporate cheating in supplying the military in wartime.

Monday, November 28, 2005

Escaping Mind Traps

A Mind Trap (see also, Jedi Mind Trick) is a picture of the world that is self-reinforcing. Once inside the mind trap, everything you see will be confirmation that the picture is correct. The mind trapper usually attaches some strings to the trap so that you give them money or follow their commands.

So how do you tell whether someone is trapping you or telling you something real about the world?

When someone tells you something real about the world, they are making a prediction of some kind. For example, if someone tells you that it is less expensive to give people prescription drugs than it is to pay for the consequences of not doing so, they're making a testable prediction.

However, if they tell you God exists, and you should act in certain prescribed ways, but that nothing you ever see will ever be in contradiction with their holy book, well... reach for your light saber! The messenger is either stuck in the trap or is the trapsetter him/herself.

Evidence cannot point to a conclusion when that conclusion does not predict the evidence. Being consistent with the evidence isn't enough for inference.

A lot of people don't understand this. This is why there are numerous mutually-exclusive belief systems that make no predictions, and why believers in such systems always see the evidence (indeed, all things) as confirming their beliefs. Once inside the trap, believers often give up their critical thinking, outsource their ethical analysis, pay the trapsetter large sums of cash, and in the worst case scenario, do harm to others.

Believing in pictures of the world that make no predictions is the surest way to self-delusion.

By the way, Intelligent Design also "predicts" whatever you observe, no matter what you observe. It, too, is a mental trap. Accept its premise and you'll see designed stuff everywhere, but nothing you ever see will be inconsistent with Intelligent Design.

Wednesday, November 23, 2005

Science and Poker

Science is a bit like poker. You have to ante up some predictions, and you have to have some skin in the game. It keeps us all honest. However, the proponents of Intelligent Design want a free pass. They never put their claims on the line because they never make a falsifiable prediction. Instead, they point to issues that remain as-yet-unexplained from the perspective of Darwinian evolutionary models, and try to count that as evidence for Intelligent Design. Sorry, but you don't get to take the Jackpot without making a bet. ID advocates deserve to be thrown out of the casino.

Wednesday, November 16, 2005

Whys are Hows

Many people claim that scientific explanations of life and cosmology can answer the "how" questions, but not the "why" questions.

That got me thinking about what the "why" question really means. Why actually means how. "Why did the chicken cross the road" means "How did the chicken come to cross the road."

This leads us into a definition of explanation.

When we ask how (or why), we are always asking about the connection between a puzzle and its environment. We are asking what must be true of the local environment such that the puzzle makes sense within it.

The physics questions, of course, fit into this pattern quite well.

"How does this bridge support the weight of the freight train that crosses it?"

There are rules in this environment (e.g., Newton's Laws, and the properties of the elements, steel in particular) that, when taken in combination with the puzzle, form a consistent whole. Given this consistent whole, the bridge can, indeed must, support the weight of the train.

Why questions aren't any different.

"Why did I choose to study physics?"

My parents encouraged my interest in science. When I showed them that I knew about a subject, I was rewarded for my study. In high school, I was good a physics because I had spent so much of my youth thinking about the concepts within it. I also wanted to know the secrets of the universe (who doesn't?). I wanted a starship and a TARDIS, if it was available. I could also get government funding to study the subject. And so on.

All of these environmental factors shaped my personality, and when the time came to decide, I could hardly make any other choice.

By the way, nothing in this analysis prohibits chance events. Consistency is the driving force, not full determinism.

However, there are some questions for which "how" questions make no sense.

When the puzzle in question is the totality of the environment, the questions become meaningless. There is no enclosing environment in which the environment can be said to fit. The environment is just a self-consistent structure, dependent on nothing external.

Here's an example. Suppose we consider a geometric structure governed by certain rules. The structure is formed by line segments in 3D space. Every line segment must meet two or more other line segments at both of its endpoints. There are many such structures, one of which would be the tetrahedron below:



Now, suppose we ask "how is the red line explained by the structure?"

We can say that the environment is such that there are intersections of pairs of lines at both endpoints of the red line, so we have to draw the red line to complete the figure according to the rules of the system. Said another way, without the red line, the environment (the other lines) would not form a consistent system.

Yet, it makes no sense to ask "how is the structure explained by the structure?"

The structure forms a self-consistent whole, and it is meaningless to ask how it is explained by an enclosing structure when there is no such enclosing structure.

Certainly, each individual part of the structure is consistent with its surrounding parts. If we can say this is true of every part of the structure, then we might say it explains itself.

If we observe the universe to be a self-consistent structure with a single, initial event, we need no further explanation of why or how the universe is consistent with anything else.

The Humanist Quiz

Hardhat



You are an atheist, a rationalist, a believer in the triumph of science and of reason over libido. You can’t stand mumbo jumbo, ritual, spiritual nonsense of any kind, and you refuse to allow for these longings in others.

Astrologers, Scientologists and new–age crystal ball creeps are no different in your view from priests, rabbis and imams. They’re all just weak–minded pilgrims on the road to easy answers. Nature as revealed by science is awesome enough for you, but it’s a nature that needs curbing and taming by us on our evolutionary journey to perfection.

Your heroes are Einstein, Darwin, Marx and — these days — Gould, Blakemore, Watson, Crick and Rosalind Franklin. Could you be hiding a little behind those absolutist views, worried that, if you let in a few doubts and contradictory ideas, the whole edifice might crumble? Loosen up a bit and try to enjoy the amazing variety of human belief systems. Don’t worry — it’s unlikely you’ll end up chanting your days away in some distant mountain cult.

What kind of humanist are you? Click here to find out.



Of course, the results aren't totally accurate. I'm not hiding, nor is Marx one of my heroes. But the quiz was fun.

Wednesday, November 09, 2005

My Problem With Religion and Metaphysics

I fear that the outcome of metaphysical thinking will be needless suffering.

I don't want to suggest that all religious people will cause suffering, but that this approach to life is intrinsically blinding and unreasonable.

Here's how I think metaphysical thinking works:

1) Arbitrarily assume metaphysics M. (Or read about someone else's assumptions in an ancient book.)

2) M is consistent with every possible experience. It's not falsifiable because it's metaphysical.

3) Attach to M the imperatives Y, e.g., Pray at specific times, don't eat shellfish, sacrifice a virgin, accumulate wealth, don't accumulate wealth, keep slaves, whatever.

Now, observe that the imperatives Y don't have to lead to any particular outcome. Every outcome is consistent with M. So any Y can be "justified" by M, even though M and Y are completely arbitrary. If sacrificing virgins causes pain and suffering, you can claim it's God's will, or that God somehow balances things out in inherently unobservable ways.

I find this to be wholly unreasonable because any behavior can be justified if you admit metaphysical thinking. A "nice" metaphysician may reject "bad" imperatives, but he cannot criticize the bad imperatives of other faiths when they use the very same derivational methods that the metaphysician used himself (i.e., blind assumption).

To render a religion reasonable, you have to require that 1) your beliefs can be falsified (i.e., M is no longer metaphysical), or 2) that there are no imperatives founded on metaphysical claims.

Fortunately, many people are unwilling to accept Y or M if the outcomes are inconsistent with what they subjectively consider to be "good" outcomes. So, for example, the vast majority of people around the world will reject militant Islam (as metaphysics) or terrorist jihad (as imperative) because they regard the acts and their outcomes to be objectionable. This is what I mean by morality determining faith, and not vice versa.

Are there any religions that might be, how shall I put it... harmless?

Well, if the religion had no imperatives, that would probably be harmless entertainment.

Another possibility is if M merely specified what outcomes were classified as desirable. In this case, science and technology would be the tools used to make those outcomes happen. I find this idea suspect, but less so than any mainstream religion.

To summarize, the main problem I have with religion is that it isolates imperatives from outcomes, by tying imperatives to metaphysics instead. I consider action without concern for outcome to be irrational.

Bush just borrowed another $5,000 in your name

Throughout the first 224 years (1776-2000) of our nation's history, 42 U.S. presidents borrowed a combined $1.01 trillion from foreign governments and financial institutions according to the U.S. Treasury Department. In the past four years alone (2001-2005), the Bush Administration has borrowed a staggering $1.05 trillion.



I'm not exactly sure how this is calculated. In October, the national debt rocketed past $8 trillion. I assume the calculation here is based only on U.S. government bonds sold directly to foreign nations.

No wonder most Americans think the country is headed in the wrong direction.

It is.


FLASHBACK: May 1, 2000
Clinton announces record payment on national debt

President Bill Clinton said Monday that the United States would pay off $216 billion in debt this year, bringing to $355 billion the amount of the nation's debt paid down in the three years since the government balanced the budget and began running surpluses.

In a written statement, Clinton said the $216 billion payment represented the largest debt paydown in American history, and he said that the federal government's long-term debt is now $2.4 trillion lower than projected to be when he first took office.

However, the U.S. government still has a long way to go before it pays down the entire national debt, which now stands at $5.7 trillion.

Tuesday, November 08, 2005

No More Common Men

From MSNBC's coverage of the Virginia Governor's race:
Before a crowd of Republican volunteers and activists Bush praised Kilgore as a man who grew up on a farm and "understands how the common man thinks." Kilgore, he said, "doesn’t have a lot of fancy airs.”
I'm so sick of this "common man" rubbish!!! Ignorance and simple-mindedness is not a virtue. It is a curse!

The President is a fine example of everything that's wrong with this approach. Here's a man who doesn't read, can't speak English, doesn't care what's going on in the world, doesn't care about the people's problems, aspires to nothing, and is a disgrace to our once great nation.

We want leaders who are learned, who are diplomats, who are great orators, who appreciate the arts, who understand the sciences, and who care for the plight of the common man. And such men are not common.

Sunday, November 06, 2005

Don't Impeach Bush for Lying

A report in yesterday's New York Times makes it clear that the Bush administration quoted the claims of Iraqi exiles and Al Qaeda prisoners as justification for invading Iraq. Yet, in 2002, the CIA regarded these claims as fabrications. Armando at Daily Kos says that this shows Bush lied to the American people to spur the Iraq War. Certainly plausible.

However, there is another possibility. The White House Iraq Group may have just been saps and suckers for terrorist misdirection. The terrorists got exactly what they wanted out of 9/11, namely, an expansion of holy war on both sides. Instead, of being treated as criminals, the jihadists are treated like soldiers. (And, thanks to the abuse scandals, there's no apparent difference in prisoner status between a soldier and a terrorist). Al Qaeda couldn't have asked for a better outcome.

Bush is weak and dangerously incompetent. The first and most vital role of the executive is to protect the nation. It is for his inability to live up to this role that Bush should be impeached.

Friday, November 04, 2005

God's Defense Attorneys

Advocates of Intelligent Design (ID) claim that ID makes real predictions. In particular, they predict that there will be gaps in the fossil record, and that the designer would create life by re-using existing organic technology (i.e., we will see common descent).

Now anyone who has even watched a documentary on evolutionary biology knows that a) the fossil record has gaps, and b) that there is common descent.

ID is a scam. They claim to predict what they already know to be the case.

But what does ID really predict?

Fossils are only preserved in very rare cases, like when an animal dies and is washed into a river bed and buried in fine silt. So gaps in the fossil record are what we should expect, no matter what the origin of life.

Common descent is the one thing specifically not predicted by ID. There's no reason why a designer should reuse DNA technology in every life form, and no reason why species should appear to have common ancestry. A designer could put rabbits in the Precambrian and robot mice in the Cretaceous. That's what ID predicts. Of course, nothing like this has ever been found, so ID doesn't claim this prediction.

By itself, ID makes no real predictions, because the designer could have done anything for any reason. Instead, generic ID merely predicts that we can't explain the origins of life. That's not a falsifiable theory, and it's definitely not science.

ID could render itself a science by making specific claims about the designer. What is she like? What tools did she use, and why did she use them? Where are those tools now? How did the limitations of the designer lead to the designs we see today? Needless to say, ID proponents, who are religiously motivated, won't go there.

ID experts claim to be the peers of scientists. But they're not. They are not fellow detectives trying to solve a mystery. They are defense attorneys for God, arguing that the detectives can't prove their case. The scientific jury isn't buying it, so they have to try their case in the court of public opinion.

Wednesday, November 02, 2005

Good Night, and Good Luck

I saw this movie on Saturday night, and let me tell you, it is a great movie.

The movie covers about four weeks in 1954 at the climax of Senator Joseph McCarthy's anti-communist witch-hunts. Edward R. Murrow and the CBS newsroom courageously challenged McCarthy's fear-mongering anti-Americanism, knowing that they too would inevitably be labeled as communists by McCarthy.

At several points in the film, I wanted to cheer. I highly recommend this movie.

Tuesday, November 01, 2005

United Brotherhood of It's None of Your Damn Business

What consenting adults do in he privacy of their own homes is none of anybody else's damn business. You want to ban a woman's right to choose, porn, French fries, science education, and birth control?

Well, if you do, your guns are next, and so is your religion.

And there are good reasons to ban them both. Thousands of people die needlessly in our gun culture, and not just in gun battles between gun owners. The lives of innocent people are destroyed every day by someone else's right to own a gun. Religion? A system designed to deprive people of critical thinking? A system responsible for the deaths of billions? Sounds like a threat to national security to me.

If I can tolerate your dogmas and killing machines, I think you can tolerate my right to privacy. It's the American way.

The American way is all about freedom. Freedom comes with responsibility. People can do harm with guns, religion and sex, but Americans choose to be free anyway. You get the whole package. You don't get to pick and choose freedoms based on arbitrary criteria, and you don't have the right to use the state to tell people what to do in the privacy of their own homes.


The title of this post is taken from the film The American President.

Saturday, October 29, 2005

Mr. Opportunity Cost

That's George W. Bush's legacy. All the opportunities that were missed because of this president.

We lost the opportunity to pay off the national debt because Bush insisted on giving tax breaks to America's millionaires.

We lost the opportunity to prevent some natural disasters by not taking aggressive action on CO2 emissions. Some global warming related disasters were inevitable because the world acted too late, but instead of starting to cut emissions now, Bush just ignored the problem. Maybe we'll get another decade of disasters thanks to Bush.

We got hit on September 11th 2001 largely because Bush ignored the terrorist threat. Outgoing Clinton officials warned him that Al Qaida was threat number one. He even got a memo from the intelligence services in August. What did he do? Nothing. He just wasted time, effort and goodwill on a useless missile defense system.

America's lead in technology is fading fast. Without public investment in nanotech or alternative energy, Americans will have no economic advantage over other nations. Jobs and money will flow elsewhere because who wants to pay Americans four times as much as, say, the Indians for comparable work? Sorry kids. America was once a great nation, like ancient Greece. Then Bush became president. He opened up free trade without securing American economic advantage. The very richest Americans got much richer because they had international portfolios. Everyone else got screwed.

After 9/11, the world stood with us in solidarity. We could have created a new world order, and solved old conflicts across the globe. Nope. Bush decided to go to war for personal reasons, and now America is seen by most people around the world as a threat as big as terrorism itself. Bastard.

The military. Bush lied and sent us to war without cause and without planning. He broke every rule of the Powell Doctrine. Now thousands of soldiers and civilians have died for less than nothing. We are now less safe than we were before, and the terrorists have benefited massively from our folly.

Okay, I have places to go to day, so I'll finish this very long list some other time.

Today's missed opportunity is in Kashmir earthquake relief. The U.N. says it needs $250 million for urgent relief needs like food and helicopters. This is needed to maintain supply lines for three million people living in the region. The U.N. says that this is our last chance to keep thousands of people alive in a region that recently saw 55,000 deaths.

Bush, you idiot! Help these people! You're all "culture of life" until people get born, then you don't give a damn! So, now millions more around the world will know that the United States could have saved the lives of thousands of Muslims in the region, could have taken a leadership role, but chose not to. $250 million is a pittance for what we would all be getting.

Another day, another lost opportunity.

Sunday, October 23, 2005

Why Singularities Don't Need a Cause

Causality, the idea that everything has a prior cause, serves an important function in physics. It makes predictions possible. If future conditions do not depend on past conditions, then the universe would be unpredictable. You can think of the laws of physics as being rules that constrain the future to depend on the past.

In physics, there's also the concept of locality. Let's say that events do depend on the past, but that signals from the past can travel faster than light. In that case, there would be frames of reference in which the future appears to affect the past. Naturally, this won't do because, again, we would be unable to make any predictions. Instead, each event is dependent on prior events in its "reverse light-cone."

Your reverse light-cone contains all the things in the past that might affect your current state. This cone is big. It is roughly 300,000 kilometers in radius for each second you go back into the past. Your current state is affected by the light and gravity of Apollo hardware sitting on the Moon's Sea of Tranquility as it was a bit more than a second ago (the Moon is roughly 400,000Km away). Anyway, physics requires that events be consistently related to prior events that are in their reverse light-cone.

What would happen if there were one, single, initial event in history? Causality would be meaningless for the initial event as there would be no prior events for the initial event to depend on. In the case of the Big Bang, the reverse light-cone gets squashed so that it contains no prior events. Therefore, science can be completely consistent without the need for something to cause the first event.

I think it's interesting to consider conservation laws for initial events, too. Conservation laws, like the conservation of energy and momentum, are due to symmetries. Noether's Theorem tells us that when a physical system has a symmetry, there is a corresponding conserved charge. In the case of energy and momentum, the symmetry is that of translation through space and time. Because the laws of physics don't change between yesterday and tomorrow, or between my house and yours, then energy and momentum are conserved over that time, too.

Yet, if there is one single event at the beginning of all space and time, there is no symmetry of translation in space and time. We cannot compare the laws of physics one second before the Big Bang to those one second after the Big Bang because there was no universe to compare against beforehand. Therefore, we should not expect energy or momentum to be conserved by the first event of the Big Bang.

Thursday, October 20, 2005

What is real?


The following is based on my comments at the blog Tu Quoque.

I propose the following definition of the term "real":

A thing is real to the extent that one can settle propositions about that thing empirically (or computationally).

In a logical positivist sense, all meaningful propositions are real (e.g., "456 + 341 = 797" is empirically verifiable). Strings of meaningless symbols are also real to the extent that we can state empirically testable propositions about those strings. Likewise, people and atoms are real to the extent that propositions about them are testable.

By this standard, even fiction has some level of reality. The fictional world of J.K. Rowling's Harry Potter is real, but only to the extent that we prefix our empirical propositions by "in the non-physical construction by J.K. Rowling..." We can create propositions about Hogwarts that can be empirically tested by verifying their consistency with Rowling's construction. However, outside of that specified literary context, Hogwarts is not real.

I think we can conclude that reality isn't a simple attribute like the truth value of a proposition. Instead, reality is a demarcation of context for meaningful propositions.
Two entities are part of the same reality when the very same empirical tests can be applied to both entities.
I anticipate an objection to my claim based on a very narrow interpretation of what constitutes the "same empirical tests". The critic may ask, under my criteria, whether thunder and lightning are part of the same reality? I would answer that they are. Correlations of between empirical tests are themselves empirical. Using photodetectors and microphones, we can easily correlate thunder and lightning, but neither sensor will register anything when Hermione Granger casts a spell.

So, this is based on my definition of what the symbol "real" means. The key aspect of this definition is that it contains within it a relatively unambiguous recipe for determining whether something is real or not.

Now, you can dispute my definition. You may prefer a different definition, but my claim is that your definition is meaningless unless you have a recipe for deciding what is and what isn't real.

You see, the term "real" doesn't have a meaning until we define the term in a more precise fashion. I think much of the reason why metaphysics is so confusing to us is that we have a vague, gut, intuitive feeling for what "real" means. We then try to reason about what things are real based purely on the gut. Intuitively, it sounds like a good idea, but it's really a confusion.

Instead, let's create a set of rigorous definitions for what real means (real[0], real[1],... we'll call mine real[0]), and then we can talk logically about what things are real.

Again, you may object to my definition on the grounds that there are things that you feel are real which do not conform to my definition. However, unless you have a rigorous alternative test procedure (real[1], say), your definition is just a gut feeling, and the definition of what is real gets reduced to how each of us personally feels about it.

As with the Principle of Verifiability, my statement about what is real is merely a definition. As such it is meaningful in the logical positivist sense as long as it specifies a procedure for determining reality.

Terror Postgrads

The Director of the Canadian Security Intelligence Service says Iraq has become a "post-graduate faculty for terrorism":

"We all obviously hope the conflict in Iraq ends soon, but then worry about what all these people are going to do," he said. "They will re-migrate around the world and return home.

"At the end of the day a lot of the issues that motivate these people are so varied and different that they will carry on possibly beyond their service in Iraq and continue to be motivators, what are now well-trained, highly effective, dangerous people."

Thursday, October 13, 2005

Verifying the Principle of Verifiability

At the core of logical positivism lies the Principle of Verifiability:

the meaning of a proposition is its method of verification or falsification.
A common criticism of logical positivism is that the Principle of Verifiability is not itself verifiable or falsifiable. As I shall show, the Principle meets its own criteria.

The Principle is not an empirical observation. The Principle defines meaning as being equivalent to "having logical consequences". Being a definition for a property, the Principle's own meaning merely requires that there be a recipe for determining the value of that property. Given a proposition, the recipe is straightforward: identify other propositions (physical or analytical) that are implied by or that refute the proposition under scrutiny.

The reader may object to the use of an arbitrary definition as the founding principle of a philosophy. Who is to say what the definition of meaning really is?

Well, the logical positivist definition of meaning sets the bar very low. It would be unreasonable to say that we would know the meaning of a proposition if we could not say what the implications of that proposition were. In other words, if you want to dispute the Principle of Verifiability, you would have to claim that a proposition has meaning or sense even when one cannot state what other propositions (again, empirical or analytic) would be implied or negated by its truth.

Thus, the Principle of Verifiability is a definition, much like the definition of any other mathematical concept like "prime number". It meets its own criteria of verifiability because it lays out a procedure for determining whether a proposition has meaning, just as the Sieve of Eratosthenes lays out a procedure for finding prime numbers.

To abandon the Principle of Verifiability is to admit that a proposition can have meaning even when it has no implications.

Wednesday, October 12, 2005

Sex and Blue Skies

MSNBC's Brian Alexander has an excellent piece about the Attorney General's new War on Porn. I don't think that the government should completely ignore minor law enforcement problems just because there are higher priorities like counter-terrorism. However, as Alexander points out, studies show that porn isn't a problem! A.G. A.G. should stop wasting taxpayer dollars scanning porn sites, and go after some actual criminals.

It is my opinion that Alberto Gonzales is engaged in political pandering to two constituencies: the religious wingnuts who see sex for pleasure as the root of all evil, and a vocal minority of parents who want the government to be responsible for raising their kids their way.

I'm not saying that a parent's job is an easy one. Quite the contrary. The ubiquity of online porn makes it difficult for children surf safely. However, there's no practical alternative to conscientious parental guidance (and good Web filtering) in this case. We can't effectively police the entire Internet without disconnecting huge chunks of it. That would hurt everything from trade to democracy to human rights.

In my opinion, parents should explain to children precisely what is and isn't acceptable activity, and parents should feel justified in setting reasonable limits on their childrens' behavior. Even if that means that their kids can't take part in every teenage social event, or can't surf the Internet without some form of supervision or surveillance.

Creating safety zones for teens is time-consuming, and comes with great responsibility. Simply erecting an information shield around the child to prevent access to all things sexual doesn't sound like a workable plan to me. Young people deserve information about safe sex and their sexual development, and they should get that information from appropriate sources (e.g., their parents).

Okay, so I'm not saying anything radical, here. I reckon most people would agree that, ideally, teens should be celibate. What about sex among consenting adults?

In my view, sex is like a blue sky or a starry night. Sex is something to be enjoyed and appreciated, something that enhances our quality of life. I think it's mean-spirited and malicious to make people feel guilty for enjoying the innocent gifts that Nature has provided to us. And the pleasure of sex is an especially good gift.

This is why authoritarian efforts to stifle consensual sexual behavior, or speech about such behavior, really bothers me. If anything, we should be making sex more wonderful, more safe, more socially acceptable and more available to adults. We should be fighting the social ills that are correlated with sexual activity, not fighting or stigmatizing the act itself.

Monday, October 10, 2005

Pulp Religion

My last post was deliberately provocative, and a bit misleading.

The study shows that higher rates of Christian religiosity don't correlate with better societal health. This should probably put to rest the old assumption that if people were more religious, then society would be better off. The United States is the most Christian, most religious developed nation, and its levels of murder, suicide and STD's are much higher than in other developed nations. In other words, making America more Christian isn't necessarily going to make us better off. Not that I don't expect Christians to want more conversions, even if it does nothing to improve society.

These charts don't imply that all religion is the direct cause of social ills. Indeed, I think it's possible that some very liberal forms of Christianity may even have a net benefit.

So what are the primary causes of these problems? The first is that America has one of the highest poverty levels of any developed nation. This poverty (and there being more guns than people) probably contributes to the very high murder rate.
The U.S. also ranks something like 20th in public education. There's no national health system, and no proper support for the mentally ill.

So why is high religiosity (in this case, Christianity) correlated with these problems? My short answer is that poverty and low education standards breeds what I would call "pulp religion."

Before I describe pulp religion, let me describe "thoughtful religion." There are dedicated theologians who study at the world's great universities. Though they're not paid much, they care deeply about the truth. They trust logic and see the weaknesses of common religious arguments. They are rarely ever dogmatists of fundamentalists. Laypersons who subscribe to liberal faiths also think the same way. They know that it's absurd to believe that the Bible is literally true, but they have faith in a higher being anyway. They are essentially secular in behavior, and they use God to motivate their own good behavior.

In contrast, pulp religion is fundamentalist, dogmatic, authoritarian and commercial. Let's take these one by one.

Fundamentalist. The Bible cannot be literally true. Even if we agreed on what God wanted, the Bible still wouldn't be literally true. It is riddled inconsistencies and impossibilities, and it contradicts scientific fact.

Dogmatic. The pulp church teaches people to outsource their morality. It claims to have moral authority and to be able to set rules for behavior. Instead of sex education, they prefer useless moralizing. When the bad behavior inevitably occurs, they excuse the bad behavior by allowing its believers to assign blame to evil spirit(s).

Authoritarian. Pulp churches want to legislate their agenda. They are most distressed that they can only tell you what to do.

Commercial. Simple rule here. If your church is rich, it's a fake. It's a business like any other. Oh, except that it gets an unconstitutional tax break.

In short, America is big on pulp religion, and pulp religion is bad for society. Generally, the more educated and affluent people are, the harder it is for pulp religion to make a profit.

What America needs is national health care, a progressive tax system (where the wealthy are taxed more than the middle-class, today the wealthy pay a lower rate), and a solid investment in public education. It most certainly doesn't need public religion.

Tuesday, September 27, 2005

Religiosity and Social Ills

What is the correlation between religiosity and social ills like abortion, teen pregnancy, sexually transmitted diseases, suicide and homicide?

The correlation is quite good. As The Times says:

According to the study, belief in and worship of God are not only unnecessary for a healthy society but may actually contribute to social problems.

The research paper that is the source for these claims has some wonderful charts on the topic. It's hard to pick a favorite, but I like this one:

(U=United States)

Eschew free thought, critical thinking and intellectualism, and these are the tragic results you get.

Quoting paragraph 18 of the paper:

No democracy is known to have combined strong religiosity and popular denial of evolution with high rates of societal health. Higher rates of non-theism and acceptance of human evolution usually correlate with lower rates of dysfunction, and the least theistic nations are usually the least dysfunctional. None of the strongly secularized, pro-evolution democracies is experiencing high levels of measurable dysfunction.

Once again, thanks to Pharyngula for the link.

Sunday, September 25, 2005

Magnificent Desolation

Magnificent Desolation is the new IMAX 3D film about the Apollo Moon landings. Seeing it yesterday, I had two thoughts.

First, if you've read about Apollo 15's mission to Hadley Rille and seen the photos, you'll appreciate how difficult it is to gauge scale and distance on the Moon's surface. It always bothered me that, though I was told I was looking at a 1,500-foot structure, I couldn't see it in the photos. In this film, you get to see what it's really like. What is it like? Well, it is almost as difficult to gauge distances on the Moon in 3D as it is in 2D. However, they do show the astronauts walk to the precipice overlooking Hadley Rille, and it's very impressive. It makes you realize just how dangerous the lunar environment can be, when you can't gauge how deep the adjacent Canyon is!

Second, though I would gladly accept a NASA Moon mission assignment, I can see the benefits of telepresence. Telepresence wouldn't have to get much better than an IMAX movie to be just like the real thing (minus the lunar gravity experience, of course). Now, how much bandwidth are we talking about? IMAX's 70mm frame is 10 times the size of 35mm film. If 35mm film is equivalent to around 14 Megapixels (just a ball park estimate), we're talking 140 Megapixels per frame, 280 MP for stereo. Multiply by 24 frames per second, and 4 bytes per pixel and you get about 26.8 Gigabytes per second, uncompressed. Okay, so live viewing might be tricky (especially given the transmission and processing delays), but it needn't be live. Not a lot happens on the Moon.

Why scientists dismiss 'intelligent design'

An excellent article found on MSNBC describing why ID has no scientific leg to stand on.

There's an upcoming court test of ID in public education in Dover, Pennsylvania. There are two reasons why this should be an easy victory for science. First, as my first link points out, there are no good scientific reasons to teach ID. The second is that the only remaining reason to teach ID in science class is religious. Indeed, it appears that the ID textbook proposed by Dover used the word Creation instead of Intelligent Design in its draft form, right up until printing time. Oops!

Tuesday, September 20, 2005

Existence Confusion

We sometimes paraphrase meaningful propositions in ways that are not strictly meaningful.

Take the proposition all Carbon 14 atoms will eventually decay. Literally, this proposition can never be tested. However, physicists would accept this as meaningful because they can translate it into a meaningful proposition, namely, the mean lifetime of Carbon 14 is 5,500 years. Technically, a Carbon 14 atom need never decay (though it would be extraordinarily improbable).

When you provide me with a philosophical proposition, I can try to squeeze it into a meaningful context, or paraphrase it so it does. I can almost always do this, as I demonstrated.

However, some propositions are designed to be resistant to this sort of reformulation. Suppose you give me just such a proposition:

A necessary, uncaused being exists.

If you accept my claim that a proposition must be part of a logical model and a choice of symbols to be meaningful, then we have to identify what that context is.

Here, you use the term "exists". You might mean this in a way that is different from when we say that "this cup of tea exists." We'll rewrite your verb as $exists until we know what it means.

For everyday, physical objects, existence is predicated on a specific definition of what empirical attributes the objects have. They are said to exist not when we can imagine them, but when we observe them.

For example, if you say that "a cup of tea exists on the table", and I look at the table and find that there is only a bowl of sugar on the table, then I have falsified your claim. Without these tests the verb to exist would be useless because elephants could exist on the table just as well.

So in your proposition, what are the specific, observable qualities of this being that would afford its existence if we observed them?

If you don't have any such qualities, then the verb you are using is just $exists not normal exists.

In the latter case, what does $exists mean? Perhaps, it is the fictional interpretation of exists, e.g., Chewbacca's third heart exists if we could only do an MRI on him in the Star Wars Universe. I doubt this because you have not shown what experiment, real or fictional would validate your claim.

Your claim is that this being (whatever a being is in this context) has a property of $existence which is as yet undefined. This is what I mean when I say it is meaningless.

The fact that confused people, some philosophers among them, feel they "understand" your proposition is not adequate to make your case. People think they understand a lot of things that they don't. In this specific case, people have an intuitive sense of what existence is. In their brains there is a cluster of neurons that fires when the concept of existence is triggered. This region forms as we grow up, using the verb to exist in the coffee cup sense. However, once we have a word for this existence property, it is tempting to trigger this region of the brain out of context. It is tempting to say that existence is just an attribute of a thing that makes it real.

This is confusing to us because we intuitively think things can exist independently of their properties. Next, we start saying X exists where X is something unobservable. It sounds grammatically correct, and it seems intuitively possible, but it is actually nonsense. It is a psychological illusion.

Now, your proposition may still form part of a logical structure, but unless you can define $exists in some rigorous way, you really aren't saying anything about the world.

Suppose you provide me some other interlocking propositions. Maybe "If a being A $exists, then there is a being B that does not $exist". (I have no idea what this means, but it would seem to logically relate to your proposition.) Even in that case, none of your interlocking propositions have any empirical consequences except for their own computational self-consistency. What makes such a proposition about the world? Nothing, I would say.

Friday, September 16, 2005

LogicSat 1

Gotta get me one of these handy space satellites.

10cm on a side, built and launched for around $50,000.

Thursday, September 15, 2005

Logical Positivism: Another Angle

This post combines some of my recent statements about metaphysics with the Principle of Verifiability.


Mathematical Systems
Mathematical systems are based on axioms, propositions that are assumed to be true without proof. From these axioms we can derive theorems, or truths which follow from those axioms. Pick different axioms, and you either get a different mathematical system, or you get an inconsistent system.

Physical Theories
A physical theory is a mathematical system that is augmented with axioms of empirical fact and with a correspondence function from mathematical propositions to empirical ones. The empirical axioms are assumed to be true because they have been observed. Physical theories make predictions by stating which additional empirical axioms would be compatible with the system of propositions. If we observe some empirical axiom that is not consistent with the theory, then the theory is "falsified." Physical theories are never intended to apply over all possible empirical observations. So, a falsifying experiment does not necessarily falsify the theory completely, it might just limit its domain of applicability. Newtonian mechanics has been falsified for speeds close to the speed of light, but this has only limited its domain of applicability. We still use Newtonian mechanics to build cars and bridges.

Fictional Worlds
A fictional world is a physical theory of a world in which the empirical axioms are not fixed by our experience, but fixed by our design. Such a system could make predictions about what other fictional empirical axioms could be added. For example, we know from fictional empirical facts that some life forms in the Star Wars universe are immune to Jedi mind tricks.

Products of Systems
I can take two independent mathematical systems and compose them into a new space of propositions. For example, I take two algebraic systems, R and F, and create a new system R×F ("the product of R and F"). The propositions of R×F are like (Ri, Fj).

Propositions in R do not contradict those in F, even if they are written using the same strings of symbols. For example, there might be a proposition (x = 7, x = 5) in R×F. This is perfectly consistent because the symbol x has a different context. Propositions in R are meaningless in F because they have no logical consequences in F. This is analogous to getting two consecutive algebra problems in a workbook, one with x = 5 and one with x = 7. No problem.

Factoring
Suppose that systems R and F share some axioms. I can combine R and F into a single system by creating a new system, R+F ("R union F"), which is founded on the axioms of both systems and contains every proposition of R and F. There is no guarantee that R+F will be consistent (e.g., if R contains x = 5 and F contains x = 7).

Suppose that R+F happens to be consistent. I can factor R+F into R×F by creating the two proper subsets of the axioms of R+F, in this case the set of axioms of R and the set of axioms of F, and rebuilding them independently as R and F.

Now suppose that R+F is a physical theory. If I factor R+F into R×F, and R contains no empirical axioms, then R is purely mathematical, and F is a physical theory. R contains mathematics which is extraneous to F. Any empirical axiom can be added to R without contradiction, but not every empirical axiom can be added to F without contradiction. That is, I can factor a physical theory with extraneous mathematics into pure mathematics plus a refined physical theory. This process of refinement aims to isolate just those axioms of a theory that have bearing on empirical axioms that might later be added to the system.

Suppose I have a system of Newtonian mechanics augmented with the mathematics of noncommutive algebra (NCA), I can factor this (N+NCA) into one system of Newtonian mechanics and another system of NCA (N×NCA). The NCA system doesn't have any correspondence with empirical facts, so it is extraneous to Newtonian mechanics. In other words, NCA doesn't do anything for my theory of mechanics. It just adds irrelevant propositions to it. I could have started from a system containing Newtonian mechanics and any random mathematical system that was without a correspondence function. The lack of a correspondence function linked to the axioms of this mathematical system allows me to factor out the extraneous mathematics.

Meaning of Strings of Symbols
Suppose you provide me with a string of symbols and claim it to be a meaningful proposition, P (e.g., P: E = mc2). I must ask in which system does P have meaning? Certainly, I could locate some mathematical system M and some choice of symbols for M where this proposition has some meaning. But, by choosing an alternate symbolic representation of M, P could have the opposite meaning. So, by itself, P has no meaning. It only has meaning in the context of a logical system where P can be related to other propositions in a symbol-independent way. P only has distinct meaning in a system when we designate what strings of symbols are consistent or inconsistent with it. That is, we must designate what propositions, if true, would be consistent with P and which would falsify it. If we cannot do this, then we cannot claim to know the meaning of P. In other words, the meaning of a proposition is its method of verification or falsification.

When I give you a string of symbols representing a proposition, your brain is working to find a context (a logical system and a symbolic representation of that system) in which the proposition has meaning. The goal of logical positivism is to make these meanings clear. Intuitively, we can almost always find a meaning for a string of symbols. Unfortunately, intuition is sometimes subjective and misleading.

If I provide you with a set of propositions like 'God is good' and 'God created the universe outside of time and out of nothing', you can only make sense of these propositions by confusing different systems. You create one logical system, G, in which God is a symbol, and in which propositions like 'God is greater than everything' are true. Then you use symbols like 'universe', 'create', 'nothing', 'time', and 'good' from the system of empirical science, E. So you try to make sense of the propositions in the context of G+E. Unfortunately, because propositions about G are compatible with every possible empirical axiom, G+E is factorable into G×E. In other words, propositions about God and reality are factorable into mathematical statements and scientific reality. The metaphysical propositions drop out from experience just as any extraneous mathematics would drop out of a physical theory. Propositions about God and reality are no more about the world than propositions about noncommutative algebra and reality.


Okay, it's a first draft.

I need to refine my definition of "product". I think I can say that

P+(R×F) = (P+R)×(P+F)

(R-F)+(F-R)+(R×F) = (R+F)×(R+F) = R+F

Where R-F is the set of axioms of R not in F.

Monday, September 12, 2005

Hail Pharyngula!

Want to keep track of the creationist war on science? Look no further than P.Z. Myers' wonderful blog about evolutionary biology. It's called Pharyngula.

One of today's posts is about so-called irreducible complexity. Irreducible complexity is an invention of creationists. It is the claim that certain evolved structures, like the human eye, are not only complex, but would be useless if any of their component parts were missing. Creationists then conclude that the odds of evolution coming up with all of the pieces independently are too remote.

As usual, creationism gets to append this argument to its litany of failures. Myers' blog post explains just how seemingly complex structures can evolve. Creationists ignore the effects of mutations that are harmless and of mutations that are orthogonally beneficial. Evolution is quite capable of building systems that naively appear designed.

I shall add that I'm very impressed with Myers' ability to write great blog posts, and write them so fast. It seems to take me forever to write even the simplest post. (This post originally featured a poker analogy, but it was taking me way too long to write up.)