“Solitude, isolation, are painful things, and beyond human endurance.”

“It is a great misfortune to be alone, my friends; and it must be believed that solitude can quickly destroy reason.”

“We now know most things that can be measured in this world, except the bounds of human ambition!”

“When I returned to partial life my face was wet with tears. How long that state of insensibility had lasted I cannot say. I had no means now of taking account of time. Never was solitude equal to this, never had any living being been so utterly forsaken.”

“So is man's heart. The desire to perform a work which will endure, which will survive him, is the origin of his superiority over all other living creatures here below. It is this which has established his dominion, and this it is which justifies it, over all the world.”

“The human mind delights in grand conceptions of supernatural beings.”

“We may brave human laws, but we cannot resist natural ones.”