[6] Which, I suppose, is why Stoics put logic at the head of our curriculum – for the same reason that, before a quantity of grain can be measured, we must settle on a standard of measurement. [7] If we don’t begin by establishing standards of weight and volume, how are we going to measure or weigh anything? [8] And similarly in the present case – if we haven’t fully grasped and refined the instrument by which we analyse and understand other things, how can we hope to understand them with any precision?

