Humans, it is sometimes said, are defined by our capacity for choice. We are not moved to act merely by instinct: we choose what we do and how we do it. This is part of what it means to be human.

Immanuel Kant, the influential Enlightenment-era German philosopher, did as much as anyone to transform this once-controversial doctrine into a bit of common sense. Human life, he thought, is a series of choices. Deciding what to do is our plight. Indeed, whereas the story of Adam, Eve, and the forbidden apple is traditionally read as the tale of evil’s entry into the world, Kant reimagined it as the tale of our all-important transformation into self-conscious choosers:

The original occasion for deserting natural instinct may have been trifling. But this was man’s first attempt to become conscious of his reason as a power which can extend itself beyond the limits to which all animals are confined. . . .  [T]his was a sufficient occasion for reason to do violence to the voice of nature and, it’s protest notwithstanding, to make the first attempt at a free choice. . . .  He discovered in himself a power of choosing for himself a way of life, of not being bound without alternative to a single way, like the animals. He stood, as it were, at the brink of an abyss.