From Troilus and Cressida
ACHILLES. What are you reading?
ULYSSES. A strange fellow here / Writes me that man - how dearly ever parted, / How much in having, or without or in - / Cannot make boast to have that which he hath, / Nor feels not what he owes, but by reflection; / As when his virtues shining upon others / Heat them, and they retort that heat again / To the first giver.
ACHILLES. This is not strange, Ulysses. / The beauty that is borne here in the face / The bearer knows not, but commends itself / To others' eyes; nor doth the eye itself - / That most pure spirit of sense - behold itself, / Not going from itself; but eye to eye opposed / Salutes each other with each other's form; / For speculation turns not to itself / Till it hath travell'd, and is mirror'd there / Where it may see itself. This is not strange at all.
Cf. Plato, Self-knowledge and Lovers, I John 3.
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