In a series of op ed pieces in the New York Times, and in a well-received new book, columnist and commentator David Brooks argues that character is less a matter of reason, than a question of habit.

Echoing UVA experimental psychologist Jonathan Haidt, Brooks makes the case that, with rare exceptions, ethical decision making is instinctive, preconditioned by both our genes and by repeated habits of thought, by stories, legends and metaphor. And indeed, brain scans have long revealed that for most people, neurons linked to decision begin to fire well before neurons linked to rational analysis when most people consider questions of justice, harm, respect, loyalty, or things they see as, somehow, disgusting.

Fiction as well as fact helps shape those instinctive patterns of thought, and after the fact, helps justify them. Thus, in time, it can be argued, you are not what you eat, but what you read, and see, and hear and admire.

Be careful.