We are in the midst of an explosion of knowledge about how the human mind and brain work -- how memory comes in many different types, each stored in a different part of the brain; how our minds constantly process information outside our conscious awareness; how differences in brain function help to define differences in our personalities. A lot of this new knowledge raises provocative questions, not least about human nature.

But as disgruntled students have been saying for ages: How are we ever going to use this stuff? Chemistry...