Who feels no ills, should, therefore, fear them; and when fortune smiles, be doubly cautious, lest destruction come remorseless on him, and he fall unpitied.

To revive sorrow is cruel.

A mathematician, like a painter or a poet, is a maker of patterns. If his patterns are more permanent than theirs, it is because they are made with ideas.

A mathematician is a device for turning coffee into theorems.

What is this frog and mouse battle among the mathematicians?

...beware of mathematicians, and all those who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and to confine man in the bonds of Hell.