In the September 7 issue of The Times Literary Supplement, Simon Blackburn reviewed my book Five Proofs of the Existence of God. The following response appeared in the TLSletters page in the September 14 issue:
Even I will admit that it is not entirely unpleasant to be criticized with the panache and wit that Simon Blackburn brings to the task. All the same, I think he underestimates both the strengths of my position and the weaknesses of his own.
The broadly Humean epistemology he deploys against the Scholastic theism I defend in Five Proofs of the Existence of God requires a careful balancing act. On the one hand, Blackburn must limit the powers of human reason sufficiently to prevent them from being able to penetrate, in any substantive way, into the ultimate “springs and principles” of nature. For that is the only way to block ascent to a divine first cause – the existence and nature of which, the Scholastic says, follows precisely from an analysis of what it would be to be an ultimate explanation.
These limits have to be even more severe than those that Aristotle, Plotinus, Aquinas and other ancient and medieval philosophical theists would already draw themselves. Precisely because of its ultimacy, the divine cause of things is only barely intelligible to the human mind. Reason’s grasp of it is genuine, but only at the fingertips. Hence Aquinas’s heavy emphasis on the via negativa and the analogical use of language. The intellect gets in just under the wire. To avoid theism, the Humean has to make sure that the intellect doesn’t even get to the wire.
On the other hand, Blackburn has to make sure that this skepticism is not so thoroughgoing that it takes science and Humean philosophy down too, alongside natural theology.
It is one of the key contentions of my book that this balancing trick cannot be pulled off – that to keep reason robust enough to support science and philosophy (even Humean philosophy) as going concerns will inevitably make it robust enough to support Scholastic theism as well.
One way to see this is by way of the principle of sufficient reason, which the Humean must deny. According to the weak version of the principle that I would endorse (which owes more to Aquinas than to the excessive rationalism of Leibniz), all concrete reality is intelligible. Humeans like Blackburn cannot accept the “all” without becoming Scholastic theists. But they cannot replace it with “no” without undermining both science and their own philosophical position. So they must claim that some concrete reality is intelligible and some is not. But where to draw the line, and why there exactly?
No principled answer is forthcoming. Certainly there is no coherent way to draw it, as many atheists attempt to do, at the fundamental laws of nature. Higher-level laws are explained by lower-level laws in something like the way the book on the top of a stack is held up by the ones below it. Take away the floor, and there is nothing that gives the bottom book any power to hold up the top book. Similarly, make the fundamental laws into unintelligible brute facts, and they have no intelligibility to pass upward to higher-level laws – which in turn will have no intelligibility to pass along to the phenomena they are supposed to be explaining. The world’s being just a little bit unintelligible is like its being just a little bit pregnant. Or it is like having a cancer that metastasizes unto the remotest extremity.
Another way to see the problem is by consideration of Hume’s Fork in its contemporary guise – the conceit that if you’re not doing natural science, then the only thing left for you to be doing is “conceptual analysis,” which tells us at best how we have to think about reality, but not how reality itself really is. The trouble with this supposition is that it is itself a proposition neither of natural science nor of conceptual analysis, but rather reflects precisely the third sort of perspective which it alleges to be impossible. Faced with traditional metaphysical claims, the Humean begins with an incredulous stare. But he ends with a coprophagic grin, caught in the very act – metaphysics – he decries as philosophically unchaste.
Blackburn’s playful comparison of a divine first cause to a number ignores the rather crucial difference that numbers are (notoriously) causally inert. This is a little like saying that a living man is like a dead man, except for being living.
In summary, the trouble with Blackburn’s review is that the key questions have not really been addressed. Or rather, they have been begged.
Edward Feser
Department of Philosophy
Pasadena City College