**Note: I recently participated in the
National Novel Writing Month, and this post is an adaptation of a
chapter from that project, so it doesn't quite read like a standard
post. A more technical summary of reductionism can be found on Less
Wrong's reductionism sequence, and specifically this page.**
Plenty of materials have unique
properties, but they're not fundamentally unique. The
unique properties are traceable back to small differences in the
underlying arrangement of matter- number of valence electrons in the
outermost shell, or atomic weight, or electronegativity, etc. But
the same structure is underpinning all of it. Materials
aren't fundamentally complex, they're fundamentally simple- made up
of electrons, neutrons, and protons. That's it.
Reality isn't fractal; the huge
differences we see on the macro level don't translate to huge
differences on the atomic level. You can zoom in farther and
farther, and eventually you come to a level where everything is made
out of the same basic stuff, and it's just the arrangement of
that stuff that makes all the difference.
Thoughts and desires aren't
fundamentally complex either. Sure, they're big and complicated at a
macro level, but if you zoom in far enough, it's all electrical
charges running around in your brain. There's no substance to them,
no form, except that our bodies- our hardware- interpret them to mean
something. Thoughts aren't real things outside of the environment of
your own brain. Humans are really good at interpreting the thoughts
of other humans because we share that context- our brains know
about thoughts because our brains have thoughts. But there
isn't some 'thought' form that actually exists in physical
reality.
Consider the following thought
experiment: you write the word 'blue' on a piece of paper, and when
you place a rock down on the paper, the rock turns blue. Then, if
you put the rock down on another paper with the word 'green' written
on it, the rock turns green. What would this experimental result
mean for your belief system?
For me, it would utterly destroy my
belief system, because this result is fundamentally absurd.
The words 'blue' and 'green' don't actually mean anything on
their own. Green and blue are fundamental things, but
the words 'green' and 'blue' aren't. From the rock's point of
view- I can't believe I just said that, since rocks obviously have no
point of view- they're just a collection of ink molecules spread out
over the paper's surface. They only mean something in the context
of the language they're written in- only people who read and speak
english would know what those words meant.
If we saw this experimental result,
there's only three possibilities I could think of to explain it.
Either the rock does speak english, or someone who speaks
english is controlling the rock, or 'green' and 'blue' are real
things. Fundamental things. Things on which the laws of nature act.
Obviously the words 'green' and 'blue' aren't real things outside of
the english language, but thoughts...
And that's why religion is defeated
by reductionism. Because if what religion claims is true, then
thoughts are something other than neurons firing. And if
that's true, then the brain is just an interface for something
much bigger, much more complex. It's just a piece of machinery that
interprets the form of thoughts into electrical signals
capable of controlling material bodies.
Now you might ask, what's so wrong
with that? Isn't that what people mean when they talk about souls?
Well, that's not actually
how brains work. If you damage one part of the brain, the victim
is left unable to speak. If you damage another, he falls asleep
without warning. If you stimulate another part with electrodes, the
test subject literally becomes a sociopath, no longer hindered by
moral attachments. In the real world, the brain affects thoughts,
not the other way around. It's not that the brain is some conduit
that allows thoughts through, and brain damage means those thoughts
come through muddled or somehow less clear. It's that damaging the
brain fundamentally alters those thoughts. It alters the way
we think, not just the output. Sociopaths aren't just outputting
actions as if they have no conscience, they're thinking and
making decisions as if their conscience doesn't exist.
More fundamentally, physics only
acts on particles, not on forms. Physics doesn't care that you've
assembled the particles into the shape of an airplane- it just goes
ahead and applies gravity, strong force, weak force, and
electromagnetism to each and every particle, and calculates the
interaction of each particle with each neighboring particle, and the
result is a solid object that flies through the air if you go fast
enough. The form is important to us, but it's not important to
physics.
But even if the soul was a thing,
and even if the brain was acting purely as an interface between the
mysterious soul and the physical world, we still have a problem.
We've now posited the existence of a fundamentally complex thing-
either that, or we're positing some simple “soulitrons” that
combine to make up a soul. But the whole reason we wanted to invoke
a soul in the first place was so that we could get away from the idea
that all humans are is a complex arrangement of simple things! If
we're willing to say souls are complex groups of soulitrons, then why
aren't we willing to say that human behavior is better explained as
being complex groups of electrons, protons, and neutrons?
At this point, the religious may
raise an objection: I've already said that's it's possible someone
who speaks english is controlling the metaphorical rock. What about
God? Surely you can't rule out the mystery of God as the explanation
of a soul?
There's really two problems with
this. First, mysterious answers to mysterious questions simply
aren't helpful. And second, now we're positing God as a
fundamentally complex thing. What is God made of? Goditrons? God
is infinitely more complex than we are. We can't posit God as a
“necessary being” as a solution to the fundamental complexity problem- or, notably, the first mover problem- because the idea of God is way more complicated than, well, pretty
much any other explanation.
