The Language of Being and Reality — Letters from a Stoic

Latin cannot say what Greek philosophy demands. Letter 58 begins with Seneca and Lucilius discussing Plato and discovering that Roman speech is poverty-stricken: words have gone mouldy since Ennius and Vergil, and there is no neat Latin for ousia or even for the single syllable on, being itself. Seneca asks leave to say essentia anyway, with Cicero and Fabianus as witnesses.

That linguistic embarrassment opens a long lesson in classification. Seneca climbs from particular men and horses to animal, living things, substance, and finally that which exists, the primary genus under which everything else falls. He then outlines Plato's six ways of existing, from thought-only universals and pre-eminent God through eternal ideas, artistic form, and the fleeting sensible world, down to fictions like void and time.

The moral pivot arrives when Heraclitus reminds us that we enter the same river twice yet never the same water. We mourn the body as if it were stable while we die daily to our former selves. Seneca extracts a practical check on appetite: the things that excite the senses are denied true existence in Plato's scheme, so craving them is clinging to shadows.

The letter ends where philosophy must end for an aging Stoic: old age is welcome while mind and better self remain intact, but a ruined mind is a house one should leave, without cowardice and without stubborn performance of pain. He signs off with a joke that Lucilius will prefer his farewell to the talk of death.