The harm that theology has done is not to create cruel impulses, but to give them the sanction of what professes to be lofty ethic, and to confer an apparently sacred character upon practices which have come down from more ignorant and barbarous times.

Thinking you know when in fact you don't is a fatal mistake, to which we are all prone

When you meet with opposition, even if it should be from your husband or your children, endeavor to overcome it by argument and not by authority, for a victory dependent upon authority is unreal and illusory.

Italy, and the spring and first love all together should suffice to make the gloomiest person happy.

Very few men can be genuinely happy in a life involving continual self-assertion against the skepticism of the mass of mankind, unless they can shut themselves up in a coterie and forget the cold outer world. The man of science has no need of a coterie, since he is thought well of by everybody except his colleagues. The artist, on the contrary, is in the painful situation of having to choose between being despised and being despicable.

The road to happiness and prosperity lies in an organized diminution of work.

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