The Old Brain-in-the-Vat Trick Again
When atheists and theists argue, sooner or later someone will pull the old brain-in-the-vat trick. Typically, the atheist will criticize the theist for offering unfalsifiable arguments for God and use the brain-in-the-vat as an analogy, saying something like, "If we were all brains in vats (or living in Keanu Reeves's Matrix ), we couldn't possibly know it. So it wouldn't matter." How that refutes the theist, I'm not sure, but it's certainly true that any empirical theory that is said to be consistent with any and all conceivable states of affairs is worth little. It tells us nothing if it rules out nothing. But more can be said on the brain/vat matter. First, in serious discussion no room exists for the arbitrary. An assertion proffered without a smidgen of evidence is inadmissible. As I've said before , "what if ...?" in itself is not an argument. The brain-in-the-vat "challenge" is supposed to introduce doubt about what we have