Freedom of the will is an illusion which cannot be shaken off, but, as great philosophers have said, it is an illusion nevertheless, and it derives solely from ignorance of true causes. The more we know about the circumstances of an act, the farther away from us the act is in time, the more difficult it is to think away its consequences; the more solidly embedded a fact is in the actual world in which we live, the less we can imagine how things might have turned out if something different had happened. For by now it seems inevitable: to think otherwise would upset too much of our world oder.