... Serious Philosopher. Isn't that the whole problem expressed in two words? Euclid was arguably "more serious" as a philosopher than a mathematician -- his

... Serious Philosopher. Isn't that the whole problem expressed in two words? Euclid was arguably "more serious" as a philosopher than a mathematician -- his principal contribution was to build a logical framework around others' results. I want to start punning now -- who was more serious, Edward Teller or Richard Feynmann? -- but it's not useful. I'll simply note a certain dissonance in calling Diogenes serious, as you seem to.