Plato's Phaedo

Socrates is in prison, sentenced to die when the sun sets. In this final conversation, he asks what will become of him once he drinks the poison prescribed for his execution. Socrates and his friends examine several arguments designed to prove that the soul is immortal.

This quest leads him to the broader topic of the nature of mind and its connection not only to human existence but also to the cosmos itself. What could be a better way to pass the time between now and the sunset?