If you type “comma” and “but” into Google, the search engine will give you some autosuggestions including: “comma after but at beginning of sentence” and “is there a comma before or after but.”
According to editors and grammarians, there is no comma after the word but at the beginning of a sentence. But it is something I see a lot in sentences like “But, there were too many of them to count” or “But, we were afraid the situation would get worse.”
When I see these commas in the work of writers, I invariably cross them out. If I find just one, I’ll squiggle it out and put a question mark (or sometimes a frowny face) in the margin, hoping it is a typo. If I see another instance of but followed by a comma, I’ll strike it out again and write “no comma after but.” If I see lots of instances of the initial but with a comma, I’ll suggest that the writer see me. They rarely do.
It’s a small problem in the grand scheme of things, but I can’t help but wonder why writers adopt this punctuation. There is really only one comma rule that mentions conjunctions: a comma goes before a coordinating conjunction that separates two independent clauses.
So why would a writer put a comma after sentence-initial but?
I’ve got a few hypotheses.
One possibility is that it is an error of analogy. Writers see examples of the adverb however followed by a comma at the beginning of a sentence and make a false analogy: however means the same thing as but; a comma is needed after however; therefore a comma is needed after but. However, adverbs and conjunctions are different grammatical categories, so the analogy does not yield the right punctuation.
Another possibility is that a writer is punctuating by ear, relying on the old idea that you put a comma where you take a breath. Since but signals a disjunction, a writer might imagine a pause and insert a comma on that basis. But punctuation is not determined solely by pauses heard in our mental ear. It is (mostly) keyed to grammatical and rhetorical categories like coordinating conjunction, independent or introductory clause, essential and inessential phrases, coordinate adjectives, and so on. If pausing is the basis for the comma after but, we are dealing with a false underlying assumption leading to an error.
If we can understand why writers make the wrong analogy or internalize the wrong underlying assumption or adopt the wrong generalization, then perhaps we can get punctuation to make more sense to future generations of writers.
A third possibility is that writers notice instances of paired, parenthetical commas the first of which happens to occur after but. They might generalize from that observation to the idea that a comma is always needed. It is easy to find examples of this pattern like “But, as my music teacher always reminded me, you must practice every day,” “But, as any driver will tell you, the commute seems endless,” or “But, always remember, you must never put your finger in a light socket.” If someone is focused too locally on the comma after but and ignores the fact that it is part of a pair of commas, they might make a false generalization.
I think it is important to puzzle about problems like this. Grammar is more than just correcting errors. If we can understand why writers make the wrong analogy or internalize the wrong underlying assumption or adopt the wrong generalization, then perhaps we can get punctuation to make more sense to future generations of writers.
I’m still not sure how to get to the bottom of this. Someday, I may create a little questionnaire that I will attach as a comment to papers to see what more I can learn. Something like this:
Why did you use a comma here?
(a) To indicate a breath or pause.
(b) Because commas are used with words like However, Well, Yes, or No at the beginning of a sentence.
(c) Because a comma always follows but.
(d) Some other reason _______________________________.
Someday I will figure out this puzzling comma.
Featured image credit: “Helvetica Paintings : , comma” by veganstraightedge. CC BY 2.0 via Flickr.