When neurologists make patients’ limbs jerk by electrically zapping certain regions of their brains, the patients often insist they meant to move that arm, and they even invent reasons why. Neurologists call these erroneous, post hoc explanations confabulations, but Dr. Daniel M. Wegner, a psychologist at Harvard, prefers the catchier “intention inventions.” He suggests that whenever we explain our acts as the outcome of our conscious choice, we are engaging in intention invention, because our actions actually stem from countless causes of which we are completely unaware.