The world is like a mirror; frown at it, and it frowns at you. Smile and it smiles, too.

The virtue of some people consists wholly in condemning the vices in others.

It is easy to be tolerant of the principles of other people if you have none of your own.

Without doubt the greatest injury of all was done by basing morals on myth. For, sooner or later, myth is recognized for what it is, and disappears. Then morality loses the foundation on which it has been built.

Science is the key which unlocks the storehouses of nature.

A difficulty for every solution.

It takes two to make a marriage a success and only one to make it a failure.