Origins of the phrase “You don't need a weatherman to know which way the wind blows”?
You don't need a weatherman to know which way the wind blows.
This phrase is famously used in Subterranean Homesick Blues by Bob Dylan. The metaphor itself is so simple and powerful I'm sure it would've been a proverb by now had we weather forecasts a couple of hundred years ago. Now imagine my surprise when I learned that Dylan apparently coined the phrase himself:
Most famously, its lyric "you don't need a weatherman to know which way the wind blows" was the inspiration for the name of the American radical left group the Weathermen, a breakaway from the Students for a Democratic Society. In a 2007 study of legal opinions and briefs that found Bob Dylan was quoted by judges and lawyer more than any other songwriter, "you don't need a weatherman..." was distinguished as the line most often cited.
Does this mean that there is no factual evidence of this phrase being used prior to the song, or did he just make an existing phrase (more) popular?
I'm not trying to belittle Dylan's influence—just plain curious how far it extends in this case.
The phrase know which way the wind blows is quite old. Even the sense of "knowing the direction of public opinion" dates from at least the early nineteenth century (see The Phrase Finder).
There is a slight association between that phrase and a "weatherman" that dates from at least the early twentieth century. There was a classroom activity called "Weathervane" to teach compass directions in which one person was designated "weatherman" and called out an arbitrary "direction of the wind" (description).
Beyond those facts, there seems to be little evidence that Dylan's lyric existed as a phrase before he set it down in the Sixties. (It's hard to prove a negative, of course.)
Does this mean that there is no factual evidence of this phrase being used prior to the song, or did he just make an existing phrase (more) popular?
I can't say with complete certainty, but a Google Books search from 1700 to 1964, which was the year before the song was released, reveals only one occurrence of the phrase, which itself seems to be a reference to Bob Dylan (whether the author had a special preview to the song or Google Books recorded the publication date incorrectly, I don't know). That isn't definitive, but it is extremely unlikely the phrase was ever used before being written for the song.