To know the brain...is equivalent to ascertaining the material course of thought and will, to discovering the intimate history of life in its perpetual duel with external forces.

Intellectual beauty is sufficient unto itself, and only for it rather than for the future good of humanity does the scholar condemn himself to arduous and painful labors.

The brain is a world consisting of a number of unexplored continents and great stretches of unknown territory.

The worst part is not in making a mistake but in trying to justify it, instead of using it as a heaven-sent warning of our mindlessness or our ignorance.

In summary, all great work is the fruit of patience and perseverance, combined with tenacious concentration on a subject over a period of months or years.

It is notorious that the desire to live increases as life itself shortens.

Nothing inspires more reverence and awe in me than an old man who knows how to change his mind.