^ f. UBBARV - JScholarship - Johns Hopkins University

VISION 19
and with hate, baleful hate^' ' Some hold that each and tions' both
every affection results from the agent in its ultimately f°^g"^'^
simplest and most essential form entering through certain theory of
pores of the patient; and they say it is in this manner that "^^°°'
we see and hear and exercise all the other senses; and,
moreover, that vision takes place through air and water
and other transparent bodies, inasmuch as all these have
pores, invisible from their smallness but close together and
arranged in rows, and all the more so arranged in proportion
to their greater transparency. Some writers have laid down
this doctrine in certain instances without confining it to
cases of agency and patiency: they go further, and say that
mixture takes place only between bodies which have pores
mutually symmetrica^.' Thus it was recognized by Aristotle,
and doubtless by others, that Empedocles did endeavoii to 1 '^^
make his theory of seeing, and of perception in general,
conform to his physical (or metaphysical) theory of the
communion of all substances by pores and airoppoiai ^.
§ 9. ' Empedocles, explaining the nature of the eye as Different
organ of vision, states * that its inner part consists of fire y°°^'Öf""
and water', while the environment of this consists of earth different
and air, through which it (the internal fire) being of a subtile consequent
nature passes, as the light in a lantern ptisses through the differences
sides. The pores of the fire and water alternate in position power.
with one another. By those of fire we cognize white
objects, by those of water, black objects; for these two
sorts of objects fit into these two sets of pores respectively.
^ Arist. 404'' 13-16. ^ Arist. 324^ 26 seqq.
' If in the verses above referred to, containing the lantem-simile,
the line at xoavrja-i blavTa TCTp^aTo 6e