Nov 25

Will the AGW fraud discredit science?

In response to the mounting evidence of fraud, data falsification, and criminal conspiracy by the “hockey team” clique of climatologists pushing anthropogenic-global-warming (AGW) theory, there has been serious and concerned speculation that the collapse of this scam may damage the credibility of science in general.

This is a reasonable thing to be concerned about, given that the species of toxic slime mold known as “creationists” have been oozing all over the blogosphere with suggestions that evolutionary biology is just as bogus. I think there are three important lessons to be drawn here: one is some reassurance from the history of major scientific frauds, another is a heuristic about when we should be suspicious of “science”, and a third is the importance of transparency.

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Nov 24

Hiding the Decline: Part 1 – The Adventure Begins

From the CRU code file osborn-tree6/briffa_sep98_d.pro , used to prepare a graph purported to be of Northern Hemisphere temperatures and reconstructions.

;
; Apply a VERY ARTIFICAL correction for decline!!
;
yrloc=[1400,findgen(19)*5.+1904]
valadj=[0.,0.,0.,0.,0.,-0.1,-0.25,-0.3,0.,- 0.1,0.3,0.8,1.2,1.7,2.5,2.6,2.6,$
2.6,2.6,2.6]*0.75 ; fudge factor
if n_elements(yrloc) ne n_elements(valadj) then message,’Oooops!’
;
yearlyadj=interpol(valadj,yrloc,timey)

This, people, is blatant data-cooking, with no pretense otherwise. It flattens a period of warm temperatures in the 1940s 1930s — see those negative coefficients? Then, later on, it applies a positive multiplier so you get a nice dramatic hockey stick at the end of the century.

All you apologists weakly protesting that this is research business as usual and there are plausible explanations for everything in the emails? Sackcloth and ashes time for you. This isn’t just a smoking gun, it’s a siege cannon with the barrel still hot.

UPDATE2: Now the data is 0.75 scaled. I think I interpreted the yrloc entry incorrectly last time, introducing an off-by-one. The 1400 point (same as the 1904) is omitted as it confuses gnuplot. These are details; the basic hockey-stick shape is unaltered.

UPDATE3: Graphic is tenmporily unavailable due to a server glitch. I’m contacting the site admins about this.

Nov 23

Open-Sourcing the Global Warming Debate

The email and documents recently netjacked from the Climate Research Unit at the University of East Anglia raise serious questions about the quality of the research being used to underpin major public-policy decisions.

In the open-source software community, we understand about human error and sloppiness and the tendency to get too caught up in a pet theory. We know that the most effective way way to combat these tendencies is transparency of process — letting the code speak for itself, and opening the sources to skeptical peer review by anyone.

There is only one way to cut through all of the conflicting claims and agendas about the CRU’s research: open-source it all. Publish the primary data sets, publish the programs used to interpret them and create graphs like the well-known global-temperature “hockey stick”, publish everything. Let the code and the data speak for itself; let the facts trump speculation and interpretation.

We know, from experience with software, that secrecy is the enemy of quality — that software bugs, like cockroaches, shun light and flourish in darkness. So, too. with mistakes in the interpretation of scientific data; neither deliberate fraud nor inadvertent error can long survive the skeptical scrutiny of millions. The same remedy we have found in the open-source community applies – unsurprisingly, since we learned it from science in the first place. Abolish the secrecy, let in the sunlight.

AGW true believers and “denialists” should be able to agree on this: the data get the last word, because without them theory is groundless. The only way for the CRU researchers to clear themselves of the imputation of serious error or fraud is full disclosure of the measurement techniques, the raw primary data sets, the code used to reduce them, and of their decisions during the process of interpretation. They should have nothing to hide; let them so demonstrate by hiding nothing.

The open-source community has many project-hosting sites that are well adapted for this sort of disclosure. If they require assistance in choosing one and learning how to create and manage an open-source project, I and many others in the open-source community will be happy to provide it.

For the future, we need to restore the basic standards of science. No secrecy: no secrecy of data, no secrecy of experimental methods, no secrecy of data-reduction or modeling code. Such transparency and accountability are especially vital when the public-policy stakes are large. This is among the excellent reasons that both the US and UK have Freedom of Information Acts, and the logic of those acts has perhaps never applied more pressingly than it does here.

Nov 21

Hiding the Decline: Prologue

According to the summaries I’ve seen, the 61 megabytes of email and documents net-jacked from the Climate Research Unit a few days ago do not — quite — reify conservatives’ darkest fantasies about “the team” (as the network of professional anthropogenic-global-warming alarmists communicating through CRU likes to style itself). To do that, they’d have to contain marching orders from the Socialist International.

However, the excerpts I’ve seen are already quite damning enough; among other things, they are evidence of criminal conspiracy to violate the Freedom Of Information act. And I no longer have to speculate about the rest; I’ve downloaded the documents from Pirate Bay and will study them myself.

For those of you who have been stigmatizing AGW skeptics as “deniers” and dismissing their charges that the whole enterprise is fraudulent? Hope you like the taste of crow, because I do believe there’s a buttload of it coming at you. Piping hot.

Am I going to blog about it? Heh…try to stop me…

UPDATE: I’ve read about 10% of the material and started a file of notes on it, but been delayed by preparing for a major release on one of my projects. In the meantime, read this excellent summary with links to the original emails.

Jul 01

The Hand-Reared Cat

In a recent comment, I wrote:

Oddly enough, our cat often does come when called, and is rather good at figuring out what humans want and doing it. A few days ago a photographer came out here to take snaps of me for an AP story on NedaNet and was quite startled when I asked the cat to turn around so her head would face the camera, and she did it.

Our cat’s behavior is not doglike servility, though. She pays careful attention to human hands because she associates them with being petted, and she’s a total friction slut. As a result, you can often fetch her, or get her to move, with hand gestures. I made one that directed her attention towards the photographer.

By an odd coincidence, my wife Cathy insisted less than an hour later that I should watch a video of the Moscow Cats Theater (I’d post a link, but I haven’t found that exact one from here). And we both noticed something; as the cats are walking tightropes and so forth, the human trainers are using encouraging, guiding gestures that seem…familiar to us. And, in fact, the cats often seem visually fixated on the trainers’ hands.

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Mar 14

Sugar and the Bathroom Demon

I am now going to blog about my cat.

No, I have not succumbed to the form of endemic Internet illness in which someone believes the cuteness of his or her feline surpasses all bounds and must therefore be shared with the entire universe. But my cat’s behavior raises some interesting questions about animal (and human!) ethology, which seem worth a little thinking time. There are three things that puzzle me in particular: the nature of the bathroom demon, some aspects of her nurturing behavior, and the mystery of the purr.

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Dec 23

Alzheimer’s and Herpes

There’s been a major breakthrough in the understanding of Alzheimer’s disease. Every face-to-face friend I’ve told about this has found it fascinating, and one of my regulars has rightly suggested I should blog it. It seems many cases of Alzheimer’s may be due to brain infection by the herpes simplex Type I virus — the one that gives you cold sores. Researchers at the University of Manchester have found herpes-simplex DNA in the abnormal beta-amyloid plaques found in the brains of Alzheimer’s patients. The implications are huge.

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Dec 17

Old physicists fade away

A commenter writes, replying to my previous post on Eric and the Quantum Experts:

>Eric, you may still have a chance to revolutionize physics, since decoherence by itself may not completely solve the problem.

Alas, I am probably too old now. There is a way outside chance I could do it, yes, but,…hmm…how to explain this…

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Sep 22

Why Alternative Energy Isn’t

As oil prices recede from all-time dollar highs and some of the hot air gets let out of energy policy debates, it’s a good time to remember that here’s a key concept missing from almost every popular discussion of the subject: energy density. Specialist economists get it, but almost nobody else does. It is important to understanding why most forms of “alternative energy” are mirages, and what a sane energy policy would actually look like.

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Jul 05

Dangerous Sons

Some time back I blogged on Hotness in Hollywood. In it I gave Angeline Jolie props for making a game effort at acting in a a movie with a script so execrable that her best effort was doomed, the original Tomb Raider movie. I also praised Liv Tyler playing Arwen, who became my personal all-time favorite example of screen sexiness in the Lord Of The Rings movies. And yes, I know this means I’m a geek; that’s not news to anybody.

My wife Cathy and I saw Wanted last night. Avoid it if you can’t stand the sight of people being shot through the head; otherwise it’s a fun popcorn movie with lots of implausible but extremely well-choreographed ultraviolence. (Well, OK, I started to giggle during the last knife fight a few minutes before the ending, because with the Marine knife-fighting technique my swordmaster taught my wife and I last year either of us could have filleted those two pirouetting idiots in short order.)

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Dec 01

Mathematics versus reality

In the comments to my posting on the incoherence of Narnia, it has become apparent that some of the respondents are deeply confused about the relationship between mathematical and empirical truth. Symptoms of this confusion have included a superficially plausible but mistaken application of the Law of the Excluded Middle and an an attempt to invoke Gödel’s Incompleteness Theorem to suggest constraints on our ability to obtain empirical truth.

It’s time to bust some myths…

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Aug 28

People Getting Brighter, Culture Getting Dimmer

In response to my previous post noting that the Flynn effect turns out to be a mirage, at least two respondents have suggested that average IQ has actually been falling, and have pointed to the alleged dumbing-down of politics and popular culture in the last fifty years.

I think both those respondents and the psychometricians are correct. That is, it seems to me that during my lifetime I’ve seen evidence that average IQ has risen a little, but that other traits involved in the “smart or stupid” judgment have eroded.

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Aug 26

Out like Flynn

Renowned pychometrician Charles Murray has given us, in The
Inequality Taboo
, a concise summary of the most current science on
group differences in IQ and other measures of capability. Most of it
is not surprising to anybody who has been following the actual science
rather than press accounts severely distorted by the demands of
political correctness.

There is some new information here, however, and perhaps the most
interesting bit is that turns out to be much less to the Flynn effect
than meets the eye. The Flynn effect is the long-term rise in average
IQ scores recorded since IQ began to be measured in the early 20th
century. Advocates of the view that IQ is unimportant or meaningless
have seized on the Flynn effect to argue that IQ is either (a) a
statistical artifact, or (b) almost entirely environmentally driven
(and thus can presumptively be increased by correct social
policy).

Murray’s news is that the Flynn effect is not being driven by a
rise in average g, the measure of general mental ability that accounts
for over 50% of variance in almost all kinds of mental aptitude tests.
Since Spearman discovered the ‘g’ statistic, almost all psychometricians
have accepted that IQ is interesting precisely because it is a good
approxmation of g. Thus, the Flynn effect is basically a mirage —
it’s taking place in the noise, not the signal.

I’m not entirely sure what this means yet, and I don’t believe
Murray or other psychometricians have gotten to the bottom of it
either. But at minimum, it’s very suggestive that IQ differences are
either genetic or driven by environmental factors over which we have
little control. Spearman’s g, in particular, is notoriously
intractable. It is highly heritable according to separated-twin
studies. And while there is good evidence that it can be lowered from
its ‘natural’ genetic level by unfavorable environment (such as poor
childhood nutrition), it apparently can’t be raised by a favorable
one.

Indeed, Murray reports in a footnote evidence from a study in
Denmark that the Flynn effect has leveled off since the early 1990s.
Thus, it may be that we have already maxed out the effects of wealth
and better nutrition on the both the g and non-g components of IQ that
we can manipulate.

Jan 06

What Do You Believe That You Cannot Prove?

I wrote this for John Brockman’s 2005 Edge Question. Can’t see
any good reason not to blog it as well.


I believe that nature is understandable, that scientific inquiry is
the sharpest tool and the noblest endeavor of the human mind, and that
any “final answers” we ever get will come from it rather than from
mysticism, religion, or any other competing account of the universe.
I believe these things without being able to prove them despite — or
perhaps because of — the fact that I am a mystic myself.

Science may be the noblest endeavor of the human mind, but I believe
(though I cannot prove) that the most crippling and dangerous kind of
ignorance in the modern West is ignorance of economics, the way
markets work, and the ways non-market allocation mechanisms are doomed
to fail. Such economic ignorance is toxic, because it leads to insane
politics and the empowerment of those whose rhetoric is altruist but
whose true agenda is coercive control.

I believe that the most important moment in the history of philosophy
was when Charles Sanders Peirce defined “truth” as “predictive power”
and made it possible to talk about confirmation of hypotheses in a
non-circular way.

I believe the most important moment in the foreseeable future of
philosophy will come when we realize that mad old Nazi bastard
Heidegger had it right when he said that we are thrown into the world
and must cope, and that theory-building consists of rearranging our
toolkit for coping. I believe the biggest blind spot in analytical
philosophy is its refusal to grapple with Heidegger’s one big insight,
but that evolutionary biology coupled with Peirce offers us a way to
stop being blind. I beleve that when the insights of what is now
called “evolutionary psychology” are truly absorbed by philosophers,
many of the supposedly intractable problems of philosophy will vanish.

I believe, but don’t know how to prove, a much stronger version of the
Sapir-Whorf hypothesis than is currently fashionable. That is, I
believe the way humans think is shaped in important ways by the
linguistic categories they have available; thinking outside those
categories is possible but more difficult, has higher friction costs.
Accordingly, I believe that some derivation of Alfred Korzybski’s
discipline of General Semantics will eventually emerge as an essential
tool of the first mature human civilizations.

I believe, but don’t know how to prove, that Julian Jaynes was on to
something very important when he wrote about the origin of
consciousness in the breakdown of the bicameral mind.

I judge that that “dark matter” is no better than phlogiston as an
explanatory device, and therefore believe without being able to prove
it that there is something very deeply wrong with the standard model
of cosmology.

I believe, but cannot prove, that the “knowledge interpretation” of
quantum mechanics is pernicious nonsense, and that physical theorists
will essentially develop some testable form of nonlocal realism.

I believe, but cannot prove, that global “AIDS” is a whole cluster of
unrelated diseases all of which have been swept under a single rug for
essentially political reasons, and that the identification of HIV as
the sole pathogen is likely to go down as one of the most colossal
blunders in the history of medicine.

Much of the West’s intelligentsia is persistently in love with
anything anti-Western (and especially anti-American), an infatuation
that has given a great deal of aid and comfort to tyrants and terrorists
in the post-9/11 world. Besides these obvious political consequences,
the phenomenon Julian Benda famously called le trahison des
clercs
has laid waste to large swathes of the soft sciences
through ideologies like deconstructionism, cultural relativism, and
postmodernism.

I believe, but cannot prove, that le trahison des clercs is
not a natural development of Western thought but a creation of
deliberate propaganda, directly traceable to the successes of Nazi and
Stalinist attempts to manipulate the climate of opinion in the early
and mid-20th century. Consequently I believe that one of the most
difficult and necessary tasks before us in the next half century will
be to banish the influence of totalitarian nihilism from science in
particular and our culture in general.

I know how to prove, or at least convincingly demonstrate, that
open-source software development produces better results than
secrecy and proprietary control. I believe that the same advantage
applies to any other form of engineering or applied science in which
the limiting factor of production is skilled human attention, but I
don’t know how to prove that general principle.

Oct 19

Predictability, Computability, and Free Will

I’ve been reading some philosophical discussion of the free-will/determism question recently. Quite a number of years ago I discovered a resolution of this question, but never did anything with it because I assumed I had simply reinvented a well-known position and could not really contribute anything to the debate. However, the research I’ve done recently suggests that my resolution of the question is actually a novel one.

Like a lot of philosophy, the discussion of free will and determinism I’ve seen founders on two errors. One of this is Aristotelianism, an attachment to observer-independent two-valued logic in a system of universal categories as the only sort of truth. The other is a tendency to get snarled up in meaningless categories that are artifacts of language rather than useful abstractions from observed reality.

In this essay, I hope to show that, if one can avoid these errors, the underlying question can be reduced to a non-problem. More generally, I hope to show how ideas from computability and complexity theory can be used to gain some purchase on problems in the philosophy of mind that have previously seemed intractable.

Formulating The Problem

The free-will question is classically put thus: do we really have choices, or are our actions and behavior at any given time entirely determined by previous states of the universe? Are we autonomous beings, who ourselves cause our future actions, or meat robots?

The second way of forming the question gets at the reason most philosophers have for finding it interesting. What they really want to know is whether we cause our own actions and are responsible for them, or whether praise, blame, and punishment are pointless because our choices are predestined.

Thus the free-will question, which is traditionally considered part of metaphysics or the philosophy of mind, is actually motivated by central issues in moral philosophy. At the end of this essay, we will consider the implications of my proposal for moral philosophy.

Classical Determinism And Its Problems

The ways philosophers have traditionally asked these questions conceal assumptions that are false in fact and logic. First, the evidence says we do not live in the kind of universe where classical determinism is an option. In almost all current versions of physical theory there is an irreducible randomness to the universe at the quantum level. Thus, even if we knew the entire state of the universe at any given moment, its future states would not be determined; we can at best predict the probability distribution of those states.

Another characteristic of quantum theory is that observation perturbs the system being observed. Let’s sidestep that for the moment and introduce the concept of a perfect observer, with infinite computational capacity and the ability to take infinitely precise measurements in zero time without perturbing the system under observation. In a universe with quantum randomness, even this perfect observer cannot know the future.

Matters are worse for imperfect observers, who have only finite computational capacity, can take only finitely accurate measurements, and perturb what they measure when they measure it. Even in theories that preserve physical determinism, imperfect observers have two additional problems. One is that they perturb what they observe; the other is sensitive dependence on initial conditions.

Two physical systems that are measurably identical to an imperfect observer and evolve by the same deterministic laws can have different futures because unmeasurably small differences between their present states are chaotically amplified over time — and some of those unmeasurable differences may be produced by the act of observation!

Even in the absence of sensitive dependence on initial conditions, though, an imperfect observer’s attempt to predict the future may fail without warning because his finite computer loses information to round-off errors (there are more subtle limits arising from finite storage capacity, but round-off errors will stand as a readily comprehensible representative of them). And like it or not, human beings are imperfect observers. So even without quantum indeterminacy, we cannot know the future with certainty.

For philosophical purposes, quantum indeterminacy and sensitive dependence on initial conditions in classical (non-quantum) systems have nearly indistinguishable effects. Together, they imply that classical determinism is not an option for imperfect observers, even in the unlikely case that quantum reality is not actually rolling dice.

Non-Classical Determinism and Irreducible Randomness

Philosophers have tended to make a fast leap from the above insight to the conclusion that humans do in fact have free will — but this conclusion is a logic error brought on by Aristotelian thinking. There is an unexcluded middle here: we may be meat robots in a universe that rolls dice, both non-determined and non-autonomous.

Most people (even most philosophers) find the idea that we are puppets on random strings even more repugnant than classical determinism. In classical determinism there is at least a perfect-observer view from which the story makes sense. The religiously inclined can believe in that perfect observer and identify it with God, and the rest of us can take some sort of fatalistic comfort in the face of our adversities that things could not after all have been any different.

In the indeterminate universe we seem to inhabit, the only way for even a god to know the future would be for it to intervene in every single collapse of a quantum state vector, and thereby to create that future by a continuous act of will. But if that were so, the behavior of all the matter in our bodies could be nothing but the god’s will. We’re back to determinism here, but it’s one in which a god is the sole causal agent of everything — good, evil, and apparent randomness. Some varieties of Hindu theology actually read like this; one rather lovely version has it that the entire universe is simply the vibration of the voice of the god Atman (or Brahman) chanting a giant “OM!” and will end untold eons in the future when He next draws breath. In the West this position has been called “occasionalism”.

The trouble with occasionalism is that it’s untestable. There is no observation we can make from within the universe to establish causal intervention from outside it. If we could do so, we would simply extend our conception of “the universe” to the larger domain within which causality operates — including the mind of Atman. The testability problem would immediately re-present itself. (This, of course, is a slightly subtler version of the standard rebuttal to the “First Cause” argument for the existence of a creator-God.)

For those of us unwilling to take occasionalism on pure faith, then, free will is about the only comfort an indeterminate universe can offer. Our experience of being human beings is that some of the time our behavior is forced by factors beyond our control (for example, if we fall off a cliff we will accelerate at a rate independent of our desire or will about the matter), but that at other times we make unforced choices that at least seem to causally originate within our own minds and not elsewhere.

To carry the discussion further, we need to decide what the term “free will” means. Our challenge is to interpret this term in a way that both consistent with its ordinary use and fits into a larger picture that is rationally consistent with physical theory. Try as I might, I can only see two possible ways to accomplish this. One has to do with autonomy, the other with unpredictability.

The Autonomy Interpretation of “Free Will”, And Its Problems

Most people, if pressed, would probably come up with some version of the autonomy interpretation. All the philosophical accounts of “free will” I’ve ever seen are based on it. We have no problem with the idea that our choices are caused, or even determined by, our previous thoughts, but the intuitive notion of free will is that our thoughts themselves are free. This implies that the measure of a human’s degree of “free will” is the degree to each human being’s history of mental states is autonomous from the rest of the universe — not caused by it, but capable of causing changes in it.

There are several problems with this account. The most obvious one is that we can often locate causal influences from the rest of the universe into our mental states. To anyone who doubts this, I recommend the experience of extreme hunger, or (better) of nearly drowning. These are quite enlightening, and philosophers would probably talk less nonsense if they retained a clearer grasp of what such experiences are like.

Less extremely, evidence from sensory-deprivation experiments suggests that a mind deprived of sensory input for too long disintegrates. Not only does the rest of the universe have causal power over our mental states, but we cannot maintain anything recognizable as a coherent mental state without that input. Which makes sense; evolutionary biology tells us that we are survival machines shaped by natural selection to cope with a reality exterior to our minds. Consciousness, reasoning, and introspection — the “higher” aspects of human mental activity that mostly concern philosophers — are recent add-ons.

None of this evidence outright excludes the possibility that there is some part or aspect of our normal mental activity that is autonomous, uncaused but causal. The real problem, the problem of logic and principle, is that we don’t know how the autonomously “free-willing” part of the mind (if it exists) can be isolated from the part that is causally driven by sensory stimuli and normal physical laws.

For materialists like myself who model the mind as a kind of software or information pattern that happens to run on an organic substrate, this is an impossible problem. We have no warrant to believe that any part of that system is causally autonomous from the rest of the universe. In fact, on functional grounds it seems quite unlikely such a part would ever evolve — what would it be good for?

But the problem is not really any simpler for dualists or mysterians, those who hold that minds have some “soul” attached that is non-physical or inaccessible to observation. That “soul” has to interact with the mind somehow. If the interaction is one-way (soul affects mind, but mind does not effect soul) then the soul is simply a sort of blind pattern- or noise-generator with no access to reality. On the other hand, if mind affects soul we are right back to the beginning of the problem — is there anything in “soul” that is neither random nor causally driven by “mind”, which we already understand to be either random or causally driven by the rest of the universe?

The basic problem here is the same as the basic problem with occasionalism. Define the “causal universe” as all phenomena with observable consequences, whether those phenomena are material or “soul” or the voice of Atman. Unless the occasionalists are right and it is all just Atman saying a trillion-year “OM!”, the concept of “soul” does not actually in itself make us any space between determinism and chance. The autonomy account of free will leaves us finally unable to locate anywhere autonomy can live.

The Predictability Account Of Free Will

I have invented a predictability account of free will which is quite different. Instead of struggling with the limits of imperfect observation, I consider them definitional. I say human beings (or any other entity to which we ascribe possession of a mind) have “free will” relative to any given observer if that observer cannot effectively predict their future mental states.

By “effectively predict” I mean that the observer, given a complete description of the mind’s state and a set of stimuli applied to that state, can predict the state of the mind after those stimuli.

Since we have access to mental states only by observing the behaviors they generate, this is arguably equivalent to saying that an entity with a mind has free will with respect to an observer if the observer cannot predict its behavior. However, I specify the term “mental state” because I think the natural-language use of the term “free will” requires that we limit the candidates for it to entities which we believe to have minds and to which we thus attribute mental states.

I am deliberately not proposing a definition or theory of “mind” in this essay, because I intend my arguments to be independent of such theory. All I require of the reader’s theory of mind is that it not exclude human beings from having one.

Can There Be Minds Without Free Will?

The first thing we need to do is establish that this definition is not vacuous. Are there any circumstances under which an entity to which we ascribe mental states can fail to have free will?

A psychologist friend of mine with whom I discussed the matter reports that the answer is “yes”. The example case she reported is a bot (software agent) named Julia designed to fool people in Internet Relay Chat rooms into believing it was a person. Julia could be convincing for a few minutes, but human beings would eventually notice mechanical patterns as they came to the edge of her functional envelope. Studies of humans interacting with Julia showed that they continued to ascribe intentions and mental states to the bot even after noticing the determinism of its behavior. The study evidence suggests that they went from modeling Julia as being like a normal adult human to being like a child or a retardate.

This was not even the first such result. The AI literature reports humans projecting personhood even on much cruder early bots such as the famous ELIZA simulation of a Rogerian psychotherapist — and not giving up that attachment even after the shallow and mechanical algorithms used to generate responses were explained to them.

The reader may object, based on some theory of “mind”, that Julia did not actually have one. But it is possible that we are all Julia. Suppose that the human mind is a deterministic machine with a very large but finite number of states; suppose further that the logic of the mind has no sensitive dependence on initial conditions (that is, its states are coarse enough for us to measure accurately). This simplest-possible model we’ll call the “clockwork mind”. If Julia has a mind, this is the kind of mind she has.

In principle, any clockwork mind can be perfectly simulated on a computer. The computer would have to be more complex than the clockwork mind itself. To predict the state of the clockwork mind, just run the simulation faster than the original. But — and this is an important point — a clockwork mind cannot be predicted by itself, or by any clockwork mind of comparable power to itself. Thus, whatever viewpoint a hypothetical perfect observer or god might have, human beings have free will with respect to each other.

It is also worth noting that human beings could have clockwork minds even in a universe of chaotic or quantum indeterminacy. If you put enough atoms together, the Law of Large Numbers will normally swamp quantum effects. If you make the states of a finite-state machine sufficiently coarse, there won’t be unmeasurable initial-condition differences to be amplified. After all, clockwork does tick!

The Indeterminate Mind

It is unlikely that humans have clockwork minds. The anatomy and physiology of the brain suggests strongly that it has chaotic indeterminacy. It may have quantum indeterminacy as well (the mathematician Roger Penrose suggested this in his book The Emperor’s New Mind, one of the favored texts of the new mysterians). It is possible that the mind cannot be modeled as a finite-state machine at all.

These distinctions make little difference, because what they all have in common is that that they make the prediction problem far less tractable than for a clockwork mind. Thus, they widen the class of observers with respect to which a non-clockwork mind would have free will.

At the extreme, if human minds have intrinsic quantum uncertainty then even a perfect observer could not predict their future mental states, unless it happens to be an occasionalist god and the only cause of everything.

The most likely intermediate case is that the mind is a finite-state machine with sensitive dependence on initial conditions and an intractably large state space. In that case it might fail to have free will with respect to a perfect observer, but will have free will with respect to any imperfect observer.

Implications for Moral Philosophy

The binding I have proposed for the term “free will” does not rely on any supposed autonomy of the mind or self from external causes. From the perspective of traditional moral philosophy, it combines the worst of both worlds — a non-autonomous mind in an indeterminate universe. How, then, can humans being be appropriate subjects of praise, blame, or punishment? In what sense, if any, can human beings be said to be responsible for their actions?

The first step towards solving this problem is to realize that these questions are separable. Because we ascribe intention and autonomy to human beings and believe their future behavior is controlled primarily by those intentions, we explain acts of praise, blame, and punishment directed at human beings in terms of the supposed effects on their mental states. But this is where remembering that we have no direct access to mental states is useful; what we are actually after when we praise, blame and punish is to change observable future behaviors.

Thus, we also praise and blame and punish animals without much regard to whether they have mental states or free will. When training a kitten it is of little interest to us in what sense it might be choosing to crap on the rug; what matters is getting it to use the litterbox. Humans, like animals, are appropriate subjects of praise and blame and punishment to the extent that those communications effectively alter their behavior. The attribution of “responsibility” is at best a sort of convenient shorthand, and at worst a red herring.

In any case the question of “responsibility” is simply the question of free will in another guise, and admits the same answer within a predictive account. An observer may hold a mind “responsible” for the actions it initiates to the extent that the observer is unable to identify external causes of those actions.

This accords well with the way people normally reason about responsibility. If all we know of a man is that he murdered someone in a fit of rage, our inclination is to hold him responsible. But if we then learn that he was unwittingly dosed with PCP, we have an external cause for the rage and can no longer consider him fully responsible.

Conclusion

The predictivist account of free will I have proposed here solves the classical problems with the autonomy account of free will, accords with natural-language use of the term “free will”, and is consilient with physical theory. It does so at the cost of making the ascription of free will dependent on the computational and measurement capacity of the observer.

The parallel with the way “space” and “time” are redefined in Relativity Theory is obvious. As in that theory, our intuitions about “free will” are largely valid in human-observable ranges but tend to break down at extremes. Relativity had to abandon the idea of absolute space/time; in our context, we need to abandon the ideal of the perfect observer and accept that finite computational capacity is yet another fundamental limit on theory-building.

I believe a similar change in stance is likely to prove essential to the solution of other outstanding problems in philosophy.