In order for the wheel to turn, for life to be lived, impurities are needed, and the impurities of impurities in the soil, too, as is known, if it is… - Primo Levi

Qualcuno, molto tempo fa, ha scritto che anche i libri, come gli esseri umani, hanno un loro destino, imprevedibile, diverso da quello che per loro si desiderava e si attendeva.

For human nature is such that grief and pain — even simultaneously suffered — do not add up as a whole in our consciousness, but hide, the lesser behind the greater, according to a definite law of perspective. It is providential and is our means of surviving in the camp. And this is the reason why so often in free life one hears it said that man is never content. In fact it is not a question of a human incapacity for a state of absolute happiness, but of an ever-insufficient knowledge of the complex nature of the state of unhappiness; so that the single name of the major cause is given to all its causes, which are composite and set out in an order of urgency. And if the most immediate cause of stress comes to an end, you are grievously amazed to see that another one lies behind; and in reality a whole series of others.

Tutti scoprono, più o meno presto nella loro vita, che la felicità non è realizzabile, ma pochi si soffermano invece sulla considerazione opposta: che tale è anche una infelicità perfetta.