...The world wouldn't be the world, without trouble.

Fire is to represent truth because it destroys all sophistry and lies; and the mask is for lying and falsehood which conceal truth.

The lie is so vile, that even if it were in speaking well of godly things, it would take off something from God's grace; and Truth is so excellent, that if it praises but small things they become noble.

Those who become enamoured of the art, without having previously applied to the diligent study of the scientific part of it, may be compared to mariners who put to the sea in a ship without rudder or compass and therefore cannot be certain of arriving at the wished for port.

Therefore, O students, study mathematics and do not build without foundations.

The eye transmits its own image through the air to all the objects which face it, and also receives them on its own surface, whence the "sensus communis" takes them and considers them.

Patience serves as a protection against wrongs as clothes do against cold.