All that one gains by falsehood is, not to be believed when he speaks the truth.

A body in motion can maintain this motion only if it remains in contact with a mover.

In justice is all virtues found in sum.

Our account does not rob the mathematicians of their science... In point of fact they do not need the infinite and do not use it.

It is the mark of an educated mind to expect that amount of exactness which the nature of the particular subject admits. It is equally unreasonable to accept merely probable conclusions from a mathematician and to demand strict demonstration from an orator.

The final cause, then, produces motion through being loved.

There is more evidence to prove that saltness [of the sea] is due to the admixture of some substance, besides that which we have adduced. Make a vessel of wax and put it in the sea, fastening its mouth in such a way as to prevent any water getting in. Then the water that percolates through the wax sides of the vessel is sweet, the earthy stuff, the admixture of which makes the water salt, being separated off as it were by a filter.