A human being does at all times only what he wills, and yet does it necessarily. But that rests on the fact that he is what he wills: for out of what he is everything that he does at any time follows necessarily.
the Two Fundamental Problems Of Ethicsby arthur Schopenhauer
Under presupposition of free will each human action would be an inexplicable miracle – an effect without cause. And if one dares the attempt to make such a liberum arbitrium indifferentiae imaginable to oneself, one will soon become aware that here the understanding quite genuinely comes to a standstill: it has no form for thinking of such a thing.