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.

Physical pain is easily forgotten, but a moral chagrin lasts indefinitely.

In my own view, some advice about what should be known, about what technical education should be acquired, about the intense motivation needed to succeed, and about the carelessness and inclination toward bias that must be avoided is far more useful than all the rules and warnings of theoretical logic.

Intellectual work is an act of creation. It is as if the mental image that is studied over a period of time were to sprout appendages like an ameba—outgrowths that extend in all directions while avoiding one obstacle after another—before interdigitating with related ideas.

If a photographic plate under the center of a lens focused on the heavens is exposed for hours, it comes to reveal stars so far away that even the most powerful telescopes fail to reveal them to the naked eye. In a similar way, time and concentration allow the intellect to perceive a ray of light in the darkness of the most complex problem.

As long as our brain is a mystery, the universe, the reflection of the structure of the brain will also be a mystery.

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