1: Zeno of Citium 2: Epicurus 3: unknown[13] 4: Boethius or Anaximander or Empedocles? 5: Averroes 6: Pythagoras 7: Alcibiades or Alexander the Great? 8: Antisthenes or Xenophon? 9: unknown [14][13] or the Fornarina as a personification of Love [15] or (Francesco Maria della Rovere?) 10: Aeschines or Xenophon? 11: Parmenides? 12: Socrates 13: Heraclitus (Michelangelo) 14: Plato (Leonardo da Vinci) 15: Aristotle 16: Diogenes 17: Plotinus (Donatello?) 18: Euclid or Archimedes with students (Bramante?) 19: Zoroaster 20: Ptolemy? R: Apelles (Raphael) 21: Protogenes (Il Sodoma, Perugino, or Timoteo Viti)[16]
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