My father and I just finished Necessity, the final volume of Jo Walton's Thessaly Trilogy.
An awesome and totally unpredictable (and supposedly impossible) hybrid
of Historical Fantasy, Sci-Fi, and Political Philosophy, I name this
series a masterpiece on par with the works of Diana Wynne Jones, J.K.
Rowling, and Patricia A. McKillip. In short, among the best of the best
after Tolkien.
Olympian Gods and Plato's Republic, Fate and Necessity, Robots and Aliens, Mystery and Time.

Olympian Gods and Plato's Republic, Fate and Necessity, Robots and Aliens, Mystery and Time.
Be the best self you can.
Know yourself.
Bear in mind that others have equal significance.
Farewell dear my friends (both mortals and gods) of Plato: Simmea, Pytheas Apollo, Maia, Sokrates, Arete, Crocus, Ficino, Ikarus, Athene, Jason, Marsilia, Thetis, and Hilfa.