Can Reason Withstand the Death of God?

Freddie has written a post that forces me into the odd position of defending Sam Harris; the crux of which is the claim that once we accept the human mind as being a contingent accident of evolution, we necessarily must abandon any faith in the intellectual edifices constructed by such minds:

For me, I would merely put it this way: that we do not encounter the physical universe unmediated but through a consciousness mechanism and sensory inputs that seem to be the products of  evolution . And the belief (however you want to define a belief) in evolution makes the idea of those consciousness and sensory mechanism being capable, no matter how long the time scale, of perfectly or non-contingently ordering the universe around us seem quite low. Evolution does not produce perfectly fit systems, it only eliminates those systems so unfit that they prevent survival and the propagation of genetic material. A chimpanzee’s intellect is a near-miracle, capable of incredible things, but it will never understand calculus. I could never and would never say this with deductive certainty, but it seems likely to me that our consciousness has similar limitations.

Now, far be it from me to to diss Nietzschean perspectivism (I am, after all, on record as being an intractable opponent of the Invisible Eye), but I think Freddie overplays his hand here. Contingent minds merely undermine the necessity of our being able to comprehend the world (a necessity that the faithful take quite seriously, as an old Dominican friar once explained to me), they leave open, however, the possibility of contingent minds that “just happen” to be of the sort that can make sense of the universe in which they happen to be located. Nevertheless, Freddie is right about one thing: once we eliminate necessity, we need reasons to think that our minds are of the right sort; after all, the humble Giraffe is well adapted to its environment, but will never come to understand particle physics or the workings of its own neurophysiology. How are we to know that we are not like Giraffes, only with considerably wider possible-knowledge horizons?

A simple response is that we haven’t failed yet. The theories we build in order to explain the universe around us are remarkably, even distressingly successful. Even stranger than their success is the methodology with which we go about building them. As Christopher Norris has beautifully documented, the positivist fairy-tale of open-minded scientists accumulating measurable evidence, making conjectures based on that evidence, and then seeking to refute those conjectures does not well describe the actual way that scientists operate. In fact, the process is a good deal more deductive — the vast majority of working scientists begin by assuming scientific realism, then asking what underlying, noumenal features of the world might lead to the kind of evidence that we observe, then building a theory concerning what other kinds of evidence these noumena might produce, then seeking confirmatory and disconfirmatory evidence.

If the world were actually non-objective, or even objectively real but of a kind that was inaccessible to our contingent reason, what would be the odds of this extraordinarily arrogant and presumptive process working — not just once, but over and over again, throughout human history? If mathematics were formalist or something akin to a logical game, then why would it be the case that sets of “toy” axioms rapidly turn out to be trivial or contradictory; while the axioms that seem to best model the world churn out theory after theory of incredible richness, whilst just barely shying away from having sufficient power to prove their own consistency, thereby rendering themselves inconsistent? Finally, why on earth do our mathematical theories and our scientific theories work so eerily well together? Why does Wigner’s “unreasonable effectiveness” exist?

Let us return to the giraffes! There is no evolutionary pressure to having minds that can figure out U(1) x SU(2) x SU(3) symmetry, or why it is that the spin of an electron has to be what it is (also due to symmetry constraints). Freddie might reply that the ability to perform the kind of abstraction and symbolic thinking that is useful when figuring out how to hunt or how migration patterns work leads very naturally to the kind of abstraction required to figure out particle physics, but I think this is missing the point. The question is why fundamental physics is amenable to this kind of abstraction. Why minds of our kind happen to be in a universe of this kind. The alternative is not necessarily chaos.

I’ve occasionally been fond of saying that physics might be hopeless. Recall that a giraffe is well adapted to its environment, but will never figure out the fundamental properties of the universe. Similarly, physics could be trivial — it would be if we were supermen with superbrains.

So let us turn that argument around. Suppose that there are evolutionary constraints on the kind of intelligence that can arise, such that in broadest strokes, thinking, abstracting beings that evolve will tend to think like us and not like giraffes or superbrains. I’m still intrigued by why it is that fundamental physics is not amenable to giraffes (and hence trivial for us) and not challenging for superbrains (and hence impossible for us).

In fact, if one were to take my argument further, one could almost turn it into a new fine-tuning argument. It is  an observable, contingent, historical fact that our minds are of just the right kind to be able to figure out a great deal about the universe, while keeping the figuring-out process challenging. In the space of possible world with contingent minds, that seems very unlikely. Might we take this as evidence that our minds are, in fact, non-contingent? Might the success of science give us a reason for faith?

I’ll leave Freddie to answer that one. The argument I’ve outlined above is certainly hand-wavy, and needs fleshing out. In fact, I can immediately think of two replies:

1) Fundamental physics may, in fact, turn out to be impossible for us to figure out.

2) The Turing attack: Anything a superbrain can do, we can do too. It’ll just take longer.

I believe I have responses to these replies, but I’ll hold off on employing them until necessary.

Don’t let me give you the impression that epistemic despair is the whole substance of Freddie’s post . There’s a good deal more in there, including a blistering attack on “totalizing” moral realism that seems designed to stir this blog into action. I’ll leave a reply to that thread, however, to James and the others . . . for now.