Timaeus: And to this kind of process the Giver of Titles gave, as we say, the names of “inspiration” and “expiration.” And the whole of this mechanism and its effects have been created in order to secure nourishment and life for our body, by means of moistening and cooling. For as the respiration goes in and out the inward fire attached thereto follows it; and whenever in its constant oscillations this fire enters in through the belly

Now, if nourishing substances taken in by the nostrils are diviner than those taken in by the mouth, yet they infer respiration. What, then, do they...