The masterwork of Raphael is probably his School of Athens, which, even though it is steeped heavily in Greco-Roman thought, is ironically located in the Vatican.
In the center are Plato (left) and Aristotle (right). Plato points up, as he is concerned with the spirit and the universe. Aristotle is more practical and points down to the ground, with earthly concerns. Raphael further describes these two different idealists with the Greek statues in the niches. To Plato's left is Apollo (patron of poetry), and on Aristotle's right is Athena (goddess of wisdom and reason…among other things). Do you think Raphael is "leaning" to one side, as it were—to Plato or to Aristotle's worldview? Well, Raphael's supreme use of one-point perspective gives us the answer. On the horizon line of the painting, the vanishing point (the center of the painting) is positioned exactly between the two, suggesting that the observant viewer will see both sides to the argument and will settle somewhere in between.
Other contemporary characters appear on the two sides to further demonstrate the relevance of the Ancient Greek philosophers' debates to their own time. On the steps is an aged Leonardo da Vinci, seen as a sort of Plato. On the left with his elbow on a box is Michelangelo, who is writing (he's on Plato's side, and therefore here presented as a philosopher, not a scientist). On the far right is the young profile of the artist himself: Raphael. He put himself among a group of mathematicians to make a statement about his art combining with math. This is also one of the first instances of a long line of artists adding themselves in the paintings as a sort of supplement to their signature.