So far, I have been a spectator in this theater which is the world, but I am now about to mount the stage, and I come forward masked.

Truths are more likely to be discovered by one man than by a nation

Your joy is your sorrow unmasked. And the self-same well from which your laughter rises was often-times filled with your tears.

The reading of all good books is indeed like a conversation with the noblest men of past centuries who were the authors of them, nay a carefully studied conversation, in which they reveal to us none but the best of their thoughts.

The mind effortlessly and automatically takes in new ideas, which remain in limbo until verified or rejected by conscious, rational analysis.

Here I beg you to observe in passing that the scruples that prevented ancient writers from using arithmetical terms in geometry, and which can only be a consequence of their inability to perceive clearly the relation between these two subjects, introduced much obscurity and confusion into their explanations.

I am thing that thinks: that is, a things that doubts,affirms, denies, understands a few things, is ignorant of many things, is willing, is unwilling, and also which imagines and has sensory perceptions.