Both the poem and the notes makes it clear that Shade wasn't Frost, so obviously he must have been. QED!
Seriously, in my limited reading of /Pale Fire/ commentary, I don't remember anything that said Frost was the model for Shade.
Similarities: Both were male American poets and professors who wrote in rhyme and meter, often using rural settings. Both liked to start with natural or homely themes and turn to philosophy or psychology or esthetics, often ending in self-mockery and bathos, as neither liked to write grand rhetoric. Both were fascinated by the sound of verse, though Shade sometimes played with it much less subtly than Frost.
Of Frost's six children, one son committed suicide at 17 or 18, and only two survived him, according to
http://en.wikipedia.org/wiki/Robert_Frost
Differences: Shade was 24 years younger, which probably explains why he wrote a book of free verse. Frost's poetry was much more private (as far as I've read) and slier. Frost didn't like to use rare words the way Shade did. And in my opinion, though Shade has his moments, Frost can be far better--Shade and Kinbote hit the nail on the head.
Shade lived all or almost all his life in one town; Frost lived in many places, including England. Frost was basically northern (apart from his birth in California and many winters in Florida), and Shade was nominally southern. Nabokov lived in a house belonging to Frost, but he never lived in one belonging to Shade.
I find it hard to believe Frost was more than a small part of Nabokov's inspiration. I think that if he were The Original of Shade, Nabokov would have researched him thoroughly, but Nabokov said he'd read very little of Frost beyond "Stopping by Woods on a Snowy Evening".
Jerry Friedman
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