Jonah Lehrer on the power of mental states:
The moral is that emotions influence how we process and pay attention to information, and that different kinds of cognitive tasks benefit from different moods. When we're editing our prose, or playing chess, or working through a math problem, we probably benefit from a little melancholy, since that makes us more attentive to details and mistakes. In contrast, when we're trying to come up with an idea for a novel, or have a hit a dead end with our analytical approach to a problem, then maybe we should take a warm shower and relax. The answer is more likely to arrive when we stop thinking about our problem. (It should also be noted, of course, that the same mental states can be induced with drugs, which is why so many artists experiment with benzedrine, marijuana, etc. They self-medicate to achieve the ideal mental state.)
I was talking with a fine artist the other day and he was telling me how blocked he was on a piece, and how he then smoked some pot and everything came together.
It unleashed what he wanted to express, by suppressing the analytic portion of his mind that was inhibiting him. I know this is the bleeding obvious to anyone who has a brain and an ounce of human experience but it is a truth we are somehow circumscribed from uttering in public.
There's a reason why jazz would be impossible without weed. And why much religion would have been stymied without the profound mental shifts that take place in deep meditation, or the revelations that come from long-time fasting, or the insights that emerge from psilocybin.
The West's ego still refuses to understand or own these things, out of fear or repression or a persistent category error. But repressing such things makes them no less true - for art or faith or all those modes of experience where rationalism is doomed to fail.