[144] If therefore there were but one idea of perfect equality, what has been said would be quite sufficient for the purpose. But as there are many, we must not hesitate to add some considerations which are suitable. For the word "equal" is used in one sense when speaking of numbers, as when we say that two are equal to two, and three to three; and speak of other numbers in the same manner. But in another sense when speaking of magnitude, as equal in length or breadth, or depth, which are all different proportions. For wrestler compared with wrestler, or cubit with cubit are equal in magnitude but different in power, as is the case also with measures and weights.