Don't become a mere recorder of facts, but try to penetrate the mystery of their origin.

If we could look through the skull into the brain of a consciously thinking person, and if the place of optimal excitability were luminous, then we should see playing over the cerebral surface, a bright spot with fantastic, waving borders constantly fluctuating in size and form, surrounded by a darkness more or less deep, covering the rest of the hemisphere.

It is not accidental that all phenomena of human life are dominated by the search for daily bread - the oldest link connecting all living things, man included, with the surrounding nature.

Science demands from a man all his life. If you had two lives that would not be enough for you. Be passionate in your work and in your searching.

Do not become archivists of facts. Try to penetrate to the secret of their occurrence, persistently search for the laws which govern them.

While you are experimenting, do not remain content with the surface of things.

As we have seen, bread, and especially dry bread, evokes secretion of considerably larger quantities of saliva than meat.