Borges, I’m being sarcastic. Mr M was as radical as most “new music” is today.
Was he? Is "radical" the correct term, if it connotes making change and pushing the boundaries?
My thinking has been that Mozart represented the perfection--and I don't use that term lightly--of the classical period. Sure, radical is correct in the sense of developing within the parameters of the period. But I don't think we can really call anyone's music of the 18th and early 19th century "radical" in a larger sense until the Eroica.