“What give all that is tragic, whatever its form, the characteristic of the sublime, is the first inkling of the knowledge that the world and life can give no satisfaction, and are not worth our investment in them. The tragic spirit consists in this. Accordingly it leads to resignation.”

“The vanity of existence is revealed in the whole form existence assumes: in the infiniteness of time and space contrasted with the finiteness of the individual in both; in the fleeting present as the sole form in which actuality exists; in the contingency and relativity of all things; in continual becoming without being; in continual desire without satisfaction; in the continual frustration of striving of which life consists. . . Time is that by virtue of which everything becomes nothingness in our hands and loses all real value.”

“It is easy to understand that in the dreary middle ages the Aristotelian logic would be very acceptable to the controversial spirit of the schoolmen, which, in the absence of all real knowledge, spent its energy upon mere formulas and words, and that it would be eagerly adopted even in its mutilated Arabian form, and presently established as the centre of all knowledge.”

“Night gives a black look to everything, whatever it may be.”

“The fundament upon which all our knowledge and learning rests is the inexplicable.”

“To free a man from error is to give, not to take away. Knowledge that a thing is false is a truth. Error always does harm; sooner or later it will bring mischief to the man who harbors it.”

“In our early youth we sit before the life that lies ahead of us like children sitting before the curtain in a theatre, in happy and tense anticipation of whatever is going to appear. Luckily we do not know what really will appear.”