Fresco by Raphael, 1510 - 1511, Stanza della Signatura, Vatican Palace, Rome.

The fresco is a masterful demonstration of the newly acquired art of perspective painting. Plato and Aristotle are seen in animated discussion in the centre, walking towards the viewer. Other philosopher-scientists include Socrates, Pythagoras, Euclid, Alcibiades, Diogenes, Ptolemy, Hypatia, Zoroaster, Xenophon, Eschines, Heracleitus, Sodoma, Parmenides, Averroës, Epicurus and Zeno.
Many of the historical figures are portraits of personalities from Raphael's time; the Euclid for example is a portrait of the architect Donato Bramante and the Heracleitus has the face of Michelangelo. Raphael himself can be seen standing next to the right column at the front.
Image: Vatican; public domain (Wikipedia)