When I first heard tell of Philip Zimbardo's famous prison experiment at Stanford, conducted in the summer of 1971, I confess I was much impressed by its dramatic revelations about human nature. Here, it seemed, was proof of our capacity for evil when placed in positions of power—ordinary college students transformed into cruel guards within mere days, their humanity stripped away by the simple donning of uniforms and the weight of artificial authority. Yet as I have grown older and perhaps somewhat wiser, I find myself increasingly suspicious of those grand narratives that claim to reveal fundamental truths about our species through such theatrical demonstrations.