To begin with we must take into consideration the parts of Man. For just as each nation is wont to reckon by that monetary standard with which it is most familiar so must we do in other matters. And of course man is the animal with which we are all of us the most familiar.
Now the parts are obvious enough to physical perception.
However with the view of observing due order and sequence and of combining rational notions with physical perception we shall proceed to enumerate the parts: firstly the organic and afterwards the simple or non-composite.