I'm sure you don't want to hear this, but here's my take on the Chaplin-vs.-Keaton debate, which I wrote about on my Keaton website, as follows:
Ever since I was a kid, I have been listening to the ridiculous debate about Charlie Chaplin versus Buster Keaton - which comic is funnier, less sentimental, more artistic, etc. - as though great movie comics are so plentiful that we must compare apples to oranges. For the final word on this subject, I have two quotes: One from The Silent Clowns, a priceless study of silent-movie comedy by the late critic Walter Kerr, the second a seemingly irrelevant quote about a completely different subject by Susan Sontag. (However, in Sontag's case, replace "The Doors and Dostoyevsky" with "Chaplin and Keaton," and you'll see what I mean.)
* "...[Keaton] has been hailed, here and there, not only as Chaplin's equal but as Chaplin's superior. This, I think, is waste effort, a misreading of Keaton's very values...Let Chaplin be king, and Keaton court jester. The king effectively rules, the jester tells the truth." - Walter Kerr, 1975
* "If I had to choose between the Doors and Dostoyevsky, then - of course - I'd choose Dostoyevsky. But do I have to choose?" - Susan Sontag, 1996