I'm familiar with some of Alighieri's philosophy and I tried to read the Commedia, I got a great deal of the way through but many other things got in the way and I'm not a huge fan of that style of prose.

I've not read any Virgil yet.

I feel that Plato, Socrates and Aristotle are necessary reads alongside Descartes, Hume, Locke, Bacon, Mill, Popper, Quine, Kuhn, Kant, Nietzsche, Satre, Voltaire, Russell and Chomsky.

Especially Bertrand Russell.

Maybe I'll get around to Virgil one day.