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OCaml

I've lately been learning to program in OCaml.  Having some familiarity with Haskell I'll say that, as of now, it's hardly distinguishable from Haskell to me.  Perhaps I'll change my tune in a few weeks of playing with it.  For now, though, they both seem like functional languages that incorporate object-oriented functionality, they strongly depend on recursion and pattern-matching, and both are largely seen as educational play-things rather than industrial-strength languages. 

Well, there's that stereotypical grumbling over nothing that all techy people do.  On the bright side, using OCaml is fun, and I hope to exercise and tighten my familiarity with Recursion Theory through its use. 

I'm also simultaneously getting through Hopcroft's Automata book, and that's more confusing.  The exact nature of the physical systems that he (they?) model with graphs is not transparent.  Perhaps I'm being a little too tedious in trying to match things up. 

I Can't Fight the Homunculi-Headed Robot

I don't know how to make heads or tails of this famous thought experiment from the Philosophy of Mind:  Suppose you see a person walking down the street who accidentally hits his shin against the edge of a bench.  He collapses, gripping his shin, wincing, groaning.  You would reasonably infer he's in pain. 

But in the commotion, his face hits the pavement and lo and behold, his face-plate comes off!  He wasn't a human at all!  Behind the face-plate are tiny men pushing buttons and reading panels to control the behavior of the robot they inhabit.  It seems the belief that this person was in pain was a mis-attribution of pain. 

But that's not the problem, otherwise this would be a fairly plain (if sci-fi cheesy) example of reasonably making a mistake.  Rather, Ned Block produced this example as a response to functionalism.  Functionalism was a response to behaviorism('s shortcomings).  And behaviorism was a response to ... modernity, I guess.  So let's do some speedy History of Philosophy and Science.


In the beginning people were dumb and believed in spooks.  They weren't actually dumb, but many (all?) early cultures believed that certain inanimate objects had spirits.  Most attributed spirits to the sun and moon; some were more liberal and believed rocks and other mundane things had spirits.  With the march of the progress of Science, the set of things which most people ascribed spirituality to contracted.  Angels fell out of favor, the devil was an increasingly unsatisfying answer, even god no longer existed literally in, or just beyond, the sky. 

But exactly which things are sppoks?  Clearly literal spooks, spooky ghosts, are spooks.  What about angels?  Probably.  Miracles?  I guess.  The human mind?  Well, wait a minute.  As far as we know it's not physical, at least not in a very simple and obvious way.  The idea of a square, which I may contemplate right now, is not located anywhere.  Not the idea of it, even if instances of squares exist in places. 

But Science abhors a non-physical thing we believe in.  The behaviorists in Psychology therefore believed they were advancing the march of Science by trying to identify the mind with behaviors of people--physical things that could be observed by scientists, measured, tested, and so on.  Pain for them was a tendency to wince, groan, seek relief, and so on.  Pain was identical to a set of behaviors. 

This obviously wouldn't do, though.  One can behave that way without pain, and one can have pain without behaving that way.  Enter the functionalists who would like to persist in identifying the mental with something physical.  Rather than say that pain was identical with behavior, they claimed that pain and other mental states were identical with a function. 

An analogy from one of the greatest American philosophers, David Lewis, was that of a lock.  Common sense tells us that the lock will unlock when the numbers on its pad are correctly aligned.  This is the fairly superficial understanding of what the lock is.  We may later learn through close observation and scientific discovery that in fact, the alignment of numbers coincides with the alignment of certain gaps in metal plates inside of the lock, such that when they are aligned the bolt in the lock can pass through, and unlock the lock.  The lock is defined by its function, and the unlocking mechanism is that which plays the causal role of causing the lock to unlock.  It turns out that this phrase superficially denotes the alignment of numbers on the pad, and more deeply denotes the alignment of gaps in metal plates. 

So by analogy, our superficial understanding of pain is the mental experience of it.  However, pain just is that which plays the causal role whereby crushed or torn flesh causes a certain set of behaviors like wincing.  We know it by the mental experience, but since certain physiological or neurological functions coincide with this and cause the experience of pain, then these must be the same thing.  To keep things easy, let's imagine that humans had a single pain sensation caused by something called C-fibers.  A person is in pain, we imagine, if and only if that person's C-fibers are firing.  Since this plays the right causal role, with inputs of some kind of physical damage, and outputs of pain-like behavior, it is identified with the mental experience of pain.


But the homunculi-headed robot is having none of this.  It takes the same causal inputs, the same behavioral outputs, and therefore is supposed to be in pain when it bangs its shin.  And yet, that's patently absurd.  This seems to be a counter-example to functionalism.  It's functioning the way a pained being would and yet it doesn't have pain. 

I don't know what to say to this.  Functionalism sure sounded good and right until this little monster popped up.  My theory is that perhaps, after we discovered that human pain is due to C-fibers, then the C-fibers themselves become part of the functioning that we refer to when we talk about the function of pain.  If in the history of Science we had discovered that in fact we were all actually homunculi-headed robots, and our visceral experience of pain were coincident with the tiny men pushing certain buttons, then this would in fact be the same thing as being in pain. 

Well, that's my best shot.

Politics is hard y'all

There are some things that we do rightly take to be basic principles of decency.  These things, like treating good people well, we don't have to justify further.  Some things have to be fundamental, otherwise we would face an infinite regress of justifications.  But it seems to me politics is rarely a place where truly fundamental principles are at play.  It's too derivative of more basic moral beliefs, and of tough empirical questions like what makes the economy better and how to measure it. 

Yet increasingly it seems that a political disagreement entails a deep hatred.  It is so easy to anger either side and short-circuit any productive conversation that all of politics now seems like screaming and taking advantage of momentary power. 

I think the main thing I advocate for in politics now is that politics is hard.  We can disagree and still be good people.  Our deepest held values are located somewhere else, like in how we choose to treat neighbors and friends daily, not here in politics.  The salient judgment about people in a conversation isn't whether they're a liberal or a conservative, but whether they're sincere.  If a racist wants to have a sincere conversation, where she's truly open to introspecting, offering her honest reasons, and changing her mind with adequate evidence--I'll have that conversation gladly.  The same for a communist, a theist, and anyone else. 

Sincerity matters more than nearly anything else.

The classics

Today I'm getting back to reading SICP (Structure and Interpretation of Computer Programs) and Halliday and Resnick's classic Physics text.  These are sort of like The Odyssey for CompSci and Physics in a sense, not necessarily because they are widely beloved--although I get the sense that they are at least appreciated by most academics in the relevant field.  They're classics in the sense that almost everyone in the relevant field has read them.

I like reading classics because

  1. Something must have made them a classic.  Especially the old ones that became popular before the textbook industry turned into big business with lots of corruption in university departments, gain a lot of prestige on this account.  Stewart's Calculus is fine I guess but it's not nearly as respected as it is widely used--and I suspect that some amount of kickbacks are responsible. 
  2. They get everyone on the same page.  In order to meaningfully say that you know programming, it suffices to read a book (and do the exercises, and similar projects) like SICP.  Other books also suffice, like Knuth's monster, but it's nice that we're all on basically the same page about SICP.

I'd like to develop a running list of classics.  I think I'll go do that now and make a page about it.

Free speech

I'm tutoring someone in Philosophy, focusing in free speech.  It's interesting to think about how you would defend an idea so absolutely fundamental to Western liberal society.  Former Supreme Court Justice Holmes put the problem as a cute paradox, which I will paraphrase as

If you know that you’re right about something important, while someone else contradicts you, and you know that you have the power to silence them, then it is natural to do just that. Put the other way around, if you do not silence someone’s speech, then you doubt either your correctness, importance, or power.
— Justice Oliver Wendell Holmes, but not quite

My gut tells me there's an analogy to freedom of religion.  These two freedoms are both interesting in that they're not regulations of citizens but rather regulations of the government.  We forbid the government from forbidding religions or speech.  It's actually historically interesting that, in fact, all of the Bill of Rights in America are of this form. 

But I have in mind a deeper equivalence between freedom of speech and freedom of religion.  It seems to me these freedoms keeps people from warring with each other through the government.  Even if one religion is wrong, and the vast majority of citizens agree that it's wrong, we still refuse to persecute followers of that religion.  Even if the religion is harmful to its followers and others, we refuse to regulate followers' speech and beliefs.  One reason for this is that, in societies where people try to control the religions of others, we have always seen brutality and abuse come from people who believe in the righteousness of their beliefs.  It may be fine for a while if you're the one who gets to be brutal--maybe it's not fine, but those people think it is anyway, and would not be convinced by sympathy for the oppressed.  But I think they should be very concerned for the day, which seems to inevitably come, when they are vulnerable to another group with the same oppressive tactics. 

I think the same sort of idea is true for freedom of expression.  You might want to regulate Nazi hate speech, but by accepting that the group in power gets to dictate acceptable speech acts, you should worry for the day when people hold power and enforce a set of beliefs you don't like.  I think actually the analogy extends to a lot of other topics, like gerrymandering:  You might love it or at least tolerate it when your own party benefits, but we should all oppose it on principle, always, for fear of what happens when the other side can use the same principle. 

Oddly, I always thought I disagreed with Hobbes, and yet here I am thinking that one good reason for a lot of our rights and freedoms, and constraints on government is a very Hobbesian idea by which we all lay down our arms against each other simultaneously. 

Current projects: Bayesian Statistics, Measure Theory, Automata

I've picked up a few Stats and Physics books that I just can't read, and it's because the Math is hard.  Hard in a weird way, to me anyway.  Knowing quite a good bit of Math it's strange to me that I'd pick up a book in another field and not understand the Math in it.  In the first chapter of an Econometrics book, casual appeal to a matrix form of Taylor's Theorem?  Matrix operations defined by the Dirac delta function when that never comes up as a significant topic in a Linear Algebra book. 

Well I think I need to just push harder on the Math.  I have fairly short patience tracing through the less mathematically rigorous material that is standard in these other subjects, used to build up intuition.  So I figure, more Math is always better and at the end of the tunnel I have a better chance of circling back to the other topics. 

So these days I've been working on Measure Theory and Probability Theory, in order to get me to that great Bayesian mountain: Jaynes' Probability Theory.  With Math muscles that big I'm sure most Econometric books should be no problem.  I should also pick up some advanced Linear Algebra books or maybe something on the Math of Physics, and eventually be ready to learn relativity.