When the state intervenes to insure the indoctrination of some doctrine, it does so because there is no conclusive evidence in favor of that doctrine.

The problem with the wise is they are so filled with doubts while the dull are so certain.

Science tells us what we can know but what we can know is little and if we forget how much we cannot know we become insensitive of many things of very great importance. Theology, on the other hand induces a dogmatic belief that we have knowledge where in fact we have ignorance and by doing so generates a kind of impertinent insolence towards the universe. Uncertainty in the presence of vivid hopes and fears is painful, but must be endured if we wish to live without the support of comforting fairy tales.

To avoid the various foolish opinions to which mankind are prone, no superhuman genius is required. A few simple rules will keep you, not from all error, but from silly error.

I am paid by the word, so I always write the shortest words possible.

So far I have been speaking of theoretical science, which is an attempt to understand the world. Practical science, which is an attempt to change the world, has been important from the first, and has continually increased in importance, until it has almost ousted theoretical science from men's thoughts.

Meantime, the world in which we exist has other aims. But it will pass away, burnt up in the fire of its own hot passions; and from its ashes will spring a new and younger world, full of fresh hope, woth the light of morning in its eyes.