Love can only flourish as long as it is free and spontaneous; it tends to be killed by the thought that it is a duty. To say that it is your duty to love so-and-so is the surest way to cause you to hate him or her.

One of the chief triumphs of modern mathematics consists in having discovered what mathematics really is.

The only thing that will redeem mankind is cooperation.

There seems scarcely any limit to what could be done in the way of producing a good world, if only men would use science wisely.

The conception of the necessary unit of all that is resolves itself into the poverty of the imagination, and a freer logic emancipates us from the straitwaistcoated benevolent institution, which idealism palms off as the totality of being.

One of the most interesting and harmful delusions to which men and nations can be subjected is that of imagining themselves special instruments of the Divine Will.

We know that the exercise of virtue should be its own reward, and it seems to follow that the enduring of it on the part of the patient should be its own punishment.