necessary quotes

This self-love is the instrument of our preservation; it resembles the provision for the perpetuity of mankind: it is necessary, it is dear to us, it gives us pleasure, and we must conceal it.

Even a mistake may turn out to be the one thing necessary to a worthwhile achievement.

Death is not natural for a state as it is for a human being, for whom death is not only necessary, but frequently even desirable.

The superfluous, a very necessary thing.

Criticism may not be agreeable, but it is necessary. It fulfils the same function as pain in the human body. It calls attention to an unhealthy state of things.