Whence and Whither A Narrative Perspective on Birth a[nwqen 159 Sextus, why Empedocles called himself a god; he kept his mind free from evil, and by the god within him (oJ ejn eJautw'/ qeov") he understood the god outside himself (17) (Against the Professors 1.303 cf. Against the Logicians 1.121). In his Against the Logicians 1.92-93, Sextus repeats the quotation without attributing it to Empedocles. Instead he refers to Philolaus, who said that things are understood when a certain suggevneia is possessed, since things are comprehended by their like (upo; tou' oJmoivou to; o{moion katalambavnesqai pevfuken). Sextus cites J Poseidonius as saying very much the same thing in his interpretation of Plato’s Timaeus: light is known by light, and sound by hearing since “The nature of all things ought to be apprehended by its kindred reason” (…uJpo; suggenou'" ... katalambavnesqai tou' lovgou). In these texts Sextus gives a “map” of the principle “like is known by like”. He mentions some important sources, he states both the antiquity and the importance of this epistemological principle. The principle of likeness forms a substratum to Plotinus’s logic in his Enneads: To any vision must be brought an eye adapted to what is to be seen, and having some likeness to it (to; ga;r oJrw'n pro;" to; oJrwvmenon suggene" kai; o{moion poihsavmenon dei' ejpibavllein) (18). Never did eye ; see the sun unless it had first become sunlike, and never can the soul have vision of the First Beauty unless itself be beautiful. Therefore, first let each become godlike and each beautiful who cares to see God and Beauty (Enneads I.6.9) Antiquity shared a theory that human beings had a light within, streaming forth through the eyes and meeting the light of day. The eye was likened to a light within or a lamp that made perception possible (19). This theory of vision developed a principle of perception, an epistemological conviction that like is known by like. —————— Empedocles said, `that is because he who looks for a wise man must first be wise himself` (159)”. Diogenes Laertius 9.20 attributes this saying to Xenophanes. (17) Greek philosophy shared the thought of the intellect as divine; gods and humans share a rational nature; see JARVIS, “Becoming like God through Christ: Discipleship in Romans”, 145-147. (18) The translation is taken from S. MACKENNA, Plotinus. The Ethical Treatises (The Library of Philosophical Translations 1; London 1917). Greek text, see P. HENRY – H.-R. SCHWYZER, Plotini Opera, Tomus I, Enneades I-III (Oxford 1964). (19) H.D. BETZ, “Matthew VI.22f and ancient Greek theories of vision”, Text and Interpretation. Studies in the New Testament presented to Matthew Black (eds. E. BEST – R.McL. WILSON) (Cambridge 1979) 43-56; D.C. ALLISON, Jr., “The Eye is the Lamp of the Body (Matthew 6.22-23=Luke 11.34-36)”, NTS 33 (1987) 61-83.