Man's cleverness is almost indefinite, and stretches like an elastic band, but human nature is like an iron ring. You can go round and round it, you can polish it highly, you can even flatten it a little on one side, whereby you will make it bulge out the other, but you will NEVER, while the world endures and man is man, increase its total circumference.

Truly wealth, which men spend all their lives in acquiring, is a valueless thing at the last.

Truly the universe is full of ghosts, not sheeted churchyard spectres, but the inextinguishable elements of individual life, which having once been, can never die, though they blend and change, and change again for ever.

It is not wise to neglect the present for the future, for who knows what the future will be?

It is a well-known fact that very often, putting the period of boyhood out of the argument, the older we grow the more cynical and hardened we become; indeed, many of us are only saved by timely death from moral petrification, if not from moral corruption.

We were like confirmed opium-eaters: in our moments of reason we well knew the deadly nature of our pursuit, but we certainly were not prepared to abandon its terrible delights.

Thinking can only serve to measure out the helplessness of thought.