The shadow zone [between thirty and forty] is not the threshold of death, but in some aspects it’s even harder. Here, you can see that no more untried possibilities are left for you. In other words, the present is no longer a preparation, a prelude, a waiting room, a launchpad for the future - quietly and unnoticeably, the situation had changed. What you thought to be training, turned out to be the final reality, a prelude to life became its only meaning, hopes became elusive dreams, and everything optional, tolerable, temporary turned out to be the only life you get. What hadn’t happened, won’t happen, and this much you have to accept - quietly, without fear, and, if possible, without despair.

Stanislaw Lem