Of the word ΕΙ engraven over the gate of Apollo's temple at Delphi (12)

There are some also who apply the faculties of the senses, being equal in number, to these five first bodies, seeing the touch to be firm and earthly, and the taste to perceive the qualities of savors by moisture. Now the air being struck upon is a voice and sound to the ear; and as for the other two,—the scent, which the smell has obtained for its object, being an exhalation and engendered by heat, is fiery; and the sight, which shines by reason of its affinity to the sky and light, has from them a temperature and complexion equally mingled of both. Now neither has any animal any other sense, nor the world any other nature simple and unmixed; but there has been made, as appears, a certain wonderful distribution and congruity of five to five.