A scientist's life, the author says, is indeed conflictual, formed by battles, defeats, and victories: but the adversary is always and only the unknown, the problem to be solved, the mystery to be clarified. It is never a matter of civil war; even though of different opinions, or of different political leanings, scientists dispute each other, they compete, but they do not battle: they are bound together by a strong alliance, by the common faith "in the validity of Maxwell's or Boltzmann's equations," and by the common acceptance of Darwinism and the molecular structure of DNA.

They sensed that what had happened around them and in their presence, and in them, was irrevocable. Never again could it be cleansed; it would prove that man, the human species - we, in short - had the potential to construct an enormity of pain, and that pain is the only force created from nothing, without cost and without effort. It is enough not to see, not to listen, not to act.

We collected in a group in front of their door, and we experienced within ourselves a grief that was new for us, the ancient grief of the people that has no land, the grief without hope of the exodus which is renewed in every century.

To accuse another of having weak kidneys, lungs, or heart, is not a crime; on the contrary, saying he has a weak brain is a crime. To be considered stupid and to be told so is more painful than being called gluttonous, mendacious, violent, lascivious, lazy, cowardly: every weakness, every vice, has found its defenders, its rhetoric, its ennoblement and exaltation, but stupidity hasn't.

A country is considered the more civilised the more the wisdom and efficiency of its laws hinder a weak man from becoming too weak and a powerful one too powerful.

In history and in life one sometimes seems to glimpse a ferocious law which states: to he that has, will be given; from he that has not, will be taken away.

For me chemistry represented an indefinite cloud of future potentialities which enveloped my life to come in black volutes torn by fiery flashes, like those which had hidden Mount Sinai. Like Moses, from that cloud I expected my law, the principle of order in me, around me, and in the world... I would watch the buds swell in spring, the mica glint in the granite, my own hands, and I would say to myself: "I will understand this, too, I will understand everything.