This morning, Arnold Zwicky took a look at the general question of whether language mavens' advice to "Avoid Potential Ambiguity" is actually helpful in avoiding ambiguity. He focused on the particular case of sentence-adverbial hopefully, and part of his argument was that if you're fluent in English,
you have to know that lots of people use hopefully as a sentence adverbial; it's all over the place. (I haven't run the numbers, but I'm sure that these days sentence-adverbial hopefully vastly dwarfs nominal-modifying hopefully in both colloquial and more elevated English.)
Well, here at Language Log, we aim to leave no number unrun. So I went to Mark Davies' lovely "Corpus of American English" search page at BYU, and checked a sample of 100 instances of hopefully from each of the five genres that he offers: spoken, fiction, magazines, newspapers, and academic. I assigned each example to one of the two categories "speaker-oriented" (i.e. sentence adverb meaning "it is to be hoped") and "subject-oriented" (i.e. verbal adverb of manner, meaning "in a hopeful manner").
The results, expressed as percentage of subject-oriented examples… the envelope please…
Across all the genres, the average was 17%. Leaving fiction out, the average was 5%. (The numbers would no doubt vary in different samples — but these should be reasonable ball-park figures.)
55% of the "subject-oriented" instances of hopefully in fiction were in quotatives, e.g. "'Shall I read to you?' he suggested hopefully." 21% were manners of gazing, e.g.
"That's true enough," Bonny said and looked at Phyllis hopefully.
I sipped coffee, gazing hopefully at my watch.
She pulls the hem of her skirt up to mid thigh. She looks hopefully over to Edward.
Kay looked for support from his father, and Ector looked hopefully at Myrddin, for his interpretation of events.
Walker found himself staring into them hopefully, searching for the answers he could find nowhere else.
Doug looked up at him hopefully.
The others were manners of moving, gesturing, and so on.
Since the "spoken" part of the BYU corpus involved pretty elevated discourse (transcripts of Larry King, PBS Newhour, 20/20, etc.), I checked the first 100 hopefully's in the Switchboard corpus — same result, 0% subject-oriented hopefully.
As a further check, I looked at 100 random examples from each of the 5 genres in the British National Corpus (except the Academic genre, where there were only 79 instances altogether):
Again, the manner-adverbial hopefully's are mostly in quotatives and gazes.
So we can quantify Arnold's surmise. In spoken English, even in fairly formal settings, hopefully is not ambiguous, because it's essentially never used as a manner adverb. In written English non-fiction, the manner-adverbial use is well below 10%, and probably below 5% in most genres. In fiction, the manner-adverbial usage is common, but largely limited to a few stereotyped cases — hopeful quotatives, hopeful looks and hopeful gestures account for the great majority of examples.
Since the speed and ease of linguistic perception generally tracks usage frequencies quite closely, we can turn these numbers into advice for writers. If you're writing non-fiction, don't use hopefully to mean "in a hopeful manner". If you're writing fiction, feel free to use hopefully as a manner adverb, but only to modify quotatives, verbs of looking, and verbs of motion with animate subjects. And don't use it in dialogue.
If you want, go ahead and placate the crazies by avoiding the sentence-adverbial use of hopefully that means "it is to be hoped". But don't take their advice and actually use the manner-adverbial sense, at least not without thinking very carefully about what you're doing.
Like most general prescriptions, even valid ones, this rule can certainly sometimes be broken in effective writing. But if you were to listen to most of the usage mavens on this one, you'd be wrong almost all the time.
[I've assigned this post to the category "Prescriptivist Poppycock". But I hope that's not right, because I'm the one giving the prescriptive advice here.]