 But already among the ancients, some demanded that we call all of the things that follow from the principles theorems, as did Speusippus, Amphinomus, and those around them, thinking that for the theoretical branches of knowledge the appellation ‘theorems’ was more appropriate than ‘problems’, especially in that they make their accounts about eternal things. For there is no coming-to-be among the eternal things, so that the problem could have no place with them, it requiring a coming-to-be and making of that which was not before, e.g. constructing an equilateral triangle or describing a square when a line is given, or placing a line at a given point. So they say it is better to say that all these things are, but that we look at their comings-to-be not by way of producing them but by way of knowing them, treating the things that always are as if they were coming-to-be. 