Let truth be a banner big enough to hide the man who holds it up.

Boundaries which mark off one field of science from another are purely artificial, are set up only for temporary convenience. Let chemists and physicists dig deep enough, and they reach common ground.

To render aid to the worthless is sheer waste. Rain does not freshen the Dead Sea, but only enables it to dissolve more salt.

Nature is full of by-ends. A moth feeds on a petal, in a moment the pollen caught on its breast will be wedding this blossom to another in the next county.

We despair of changing the habits of men, still we would alter institutions, the habits of millions of men.

A calculating engine is one of the most intricate forms of mechanism, a telegraph key one of the simplest. But compare their value.

Nothing cools so fast as undue enthusiasm. Water that has boiled freezes sooner than any other.