De Plantatione

It follows, therefore, of necessity that the sides of a square must be all equal to one another. And equality is the parent of justice, which is the mistress and ruler of all the virtues, so that it is now proved that this number four is the symbol of equality, and justice, and of all virtue, beyond any other number.

And the number four is likewise called "all," because it comprehends in its power the numbers up to ten, and the number ten itself. That is comprehends all the numbers up to itself is manifest to every one; but that it also comprehends [*](Leviticus xix. 25. )