There are generally two reasons for such strongly-held views.
The most commonly-cited reason is that the Oxford comma is grammatically important because it objectively reduces ambiguity, e.g.:
|No Oxford comma||I spoke to my dogs, Jack and Jill.||I spoke to two people and my dogs OR I spoke to my two dogs, named Jack and Jill|
|Oxford comma||I spoke to my dogs, Jack, and Jill.||I spoke to two people and my dogs|
In this sentence, adding the Oxford comma eliminates ambiguity.
But of course, the only reason that example works is because “dogs” is pluralized. If you take out the plural:
|No Oxford comma||I spoke to my dog, Jack and Jill.||I spoke to two people and my dog|
|Oxford comma||I spoke to my dog, Jack, and Jill.||I spoke to two people and my dog OR I spoke to one person (Jill) and my dog (Jack)|
Now adding the Oxford comma introduces ambiguity.
The critical insight is that the ambiguity arises not from the presence or lack of the Oxford comma, but from poor sentence construction. In all of the above examples, simply writing “I spoke to Jack, Jill, and my dog[s]” would eliminate any ambiguity, and whether you use the Oxford comma doesn’t matter.
In other words, the Oxford comma does not consistently increase or decrease ambiguity. For each sentence it eliminates ambiguity, there is a matching sentence where it introduces ambiguity. This in turn suggests that the real Oxford comma rule is simply to use it when it helps and not to use it when it hurts - an inconsistent rule that is really no rule at all.
As such, having a strong view on the Oxford comma is rather like having a strong view on the pronounciation of “gif” - you should use whichever pronounciation gets your point across more clearly, and most of the time, it doesn’t matter.
Of course, people do have strongly-held views on the pronounciation of “gif”, and so this perhaps explains the second reason for strongly-held views on the Oxford comma - signalling. In the grand scheme of things, the Oxford comma is trivial2 - but its very triviality makes it valuable for signalling. Caring about such a trivial grammatical detail, so the theory goes, sends the message that you are a person who cares about trivial grammatical details,3 and that you have the ability and luxury to so care because you belong to a particular educated class of society.
Or, in other words, it is not a coincidence that most who broadcast their views on the subject refer to it as the “Oxford comma”, or sometimes the “Harvard comma” - but almost never the “serial comma”.
However, the fact that the Oxford comma is, in reality, grammatically irrelevant brings me back to my aforementioned suspicion of those who have strongly-held views on the comma. In a way, caring about the Oxford comma is almost a form of counter-signalling: because the Oxford comma actually has no underlying grammatical value, a strongly-held view on the comma does little to signal one’s grammatical chops - and instead only ends up meta-signalling the desire to signal one’s grammatical chops.
By contrast, if you have a strong view on David Foster Wallace’s grammar quiz - then I’m all ears.
- Yes, I am aware of the irony. I can only plead that I am mainly expressing not my view on the comma itself, but my (strongly-held) view on views on the Oxford comma. [return]
- Unless you are Oakhurst Dairy. [return]
- A tactic relied on by law firms and Van Halen alike - if your junior associate gives you sloppily-Bluebooked work product, or if your venue gives you brown M&Ms, it’s time to go over their work more carefully. [return]