When a book and a head collide and a hollow sound is heard, must it always have come from the book?

In the world we live in, one fool makes many fools, but one sage only a few sages.

Nothing is more conducive to peace of mind than not having any opinion at all.

It is too bad if you have to do everything upon reflection and can't do anything from early habit.

A writer who wishes to be read by posterity must not be averse to putting hints which might give rise to whole books, or ideas for learned discussions, in some corner of a chapter so that one should think he can afford to throw them away by the thousand.

Imagine the world so greatly magnified that particles of light look like twenty-four-pound cannon balls.

The course of the seasons is a piece of clockwork, with a cuckoo to call when it is spring.