Quotes from Jules Henri Poincaré

To doubt everything and to believe everything are two equally convenient solutions; each saves us from thinking.

Thought is only a gleam in the midst of a long night. But it is this gleam which is everything.

Discovery is discernment, selection.

The scientist does not study nature because it is useful to do so. He studies it because he takes pleasure in it, and he takes pleasure in it because it is beautiful. If nature were not beautiful, it would not be worth knowing, and life would not be worth living.

Science is built up with facts, as a house is with stones. But a collection of facts is no more a science than a heap of stones is a house.

Principles are conventions and definitions in disguise.