“A mind stretched by a new ideanever shrinks back to its original proportions. ~”

“To reach a port we must sail, sometimes with the wind, and sometimes against it. But we must not drift or lie at anchor.”

“Every calling is great when greatly pursued.”

“I confess that altruistic and cynically selfish talk seem to me about equally unreal. With all humility I think 'whatsoever thy hand findeth to do do it with thy might ' infinitely more important...”

“You commit a sin of omission if you do not utilize all the power that is within you. All men have claims on man and to the man with special talents this is a very special claim. It is required th...”

“An older author is constantly rediscovering himself in the more or less fossilized productions of his earlier years.”

“The land of easy mathematics where he who works adds up and he who retires subtracts.”

“At the age of 45, most days in Tucson were spent feeling like I was on the summit of Mauna Kea, as I was exhibiting debilitating health symptoms that corresponded to what I saw at very high altitud...”

“The hour is only long thus, if you've waited.”