Resolved: The Oxford comma should be mandatory.

R1) Syntactic Ambiguity My opponent states that it is better to have one single rule, rather than two shaky ones, because the Oxford comma is required in some places to resolve ambiguity. He assumes that the Oxford comma never creates ambiguity, which is completely false. My opponent used a variant of the common strippers, JFK and Stalin argument to support his case. In fact, if I just altered the example slightly, it would be the Oxford comma which causes ambiguity. Consider: (I) I brought the clown, Bob and George. (II) I brought the clown, Bob, and George. In (I), it is clear that three people - the clown, Bob and George - will be brought. (II) is ambiguous: the clown, Bob, and George can be a list of three items, but Bob may also be a non-restrictive appositive that modifies the clown. Thus having a single rule the mandatory use of the comma will not eliminate all ambiguity. In formally ambiguous cases, the Oxford commma should be encouraged but even then, omission should sometimes be allowed. This is thanks to pragmatics, which allows readers to deduce meaning. For example, if I wrote a sign that says 'Please Press' above a button, you wouldn't think I'm saying 'impress the reporters' (physical context), and if I said 'Please press to flush', you wouldn't assume that impressing reporters can help you flush the toilet (linguistic context). In Buttercat's example, the definite article before clown indicates deixis, so the reader likely has some knowledge of who the clowns are. If so, it is not necessary to obligate the use of the Oxford comma there. Consider: Bob and George are my best friends. We're all fans of the DDO Clowns, who are the funniest clowns on the planet. For this party, I'm going to bring the clowns, Bob and George. In this paragraph, it is clear that Bob and George are not members of DDO Clowns, to which the clowns refers, so the meaning is clear, even without the comma. Despite formal ambiguity, it is not absolutely necessary to use the Oxford comma here. Even scientific literature allows formal ambiguity as long as meaning is clear in context. Consider this example of a three-way ambiguity from a corpus of scientific literature, quoted by Huddleston (1971) (1): Whether the animal or man actually responds by moving or speaking is, however, very seldom determined by the actions of a single receptive fibre. R2) Oration Firstly, my opponent appears to have misunderstood my C4, which is about silent reading. My opponent assumes that slowing down to increase clarity is always good. Yet imagine one is reading aloud a script where one of the characters reads out a long list for comedic effect, e.g. I'm having an apple, two pears, three bananas, ... and fifty desserts. Obviously, the list items must be spoken in rapid succession to maximise the impact of this rhetorical device. My opponent assumes that slowing down will be effective in increasing clarity. In fact, auditory scene analysis facilitates the perception of the final item of the list. For example, if I said 'Hitler, Mussolini and T..... (bus horn)', you'll still be able to hear 'Tojo'. (2) The extra pause is not needed. Thirdly, we should not make the comma necessary just because of one small benefit. If a speaker wants to use the Oxford comma to the benefit of his own oration, then sure, but we should not ban the omission of the comma in all contexts. Most writings are not scripts prepared for oration. Furthermore, a careful speaker who always pauses before and in hyperspeech is unlikely to forget this, even in the absence of the Oxford comma. R3) Supporters Of the Oxford Comma Regrettably, the whole argument here is a false appeal to authority. Style guides give prescriptive rules on the use of language in one particular register, rules which do not apply universally. The APA style, for example, is mainly applied in the academia, and is unlikely to be employed in, say, a novel. Moreover, much like any other style convention, opinions on the Oxford comma are by no means unequivocal, which is evidenced by the fact that respectable publications such as The Economist, The New York Times, The Wall Street Journal, The Times and The Guardian do not allow its use except in cases of ambiguity. The AP Stylebook, the Publishing Service's Style Manual for Authors, Editors and Printers and the MHRA Style Guide do not support its mandatory use of the comma, either. (3) I hope my opponent will excuse my temporarily lapse of pedantry, and allow me to point out his erroneous word of the term 'linguistics'. Rather than prescribing rules for language users, modern linguistics has, for the greater part of the 20th century, focused on descriptivism. For example, African American Vernacular English often omits the copula. While other variants of English do not allow the omission of the copula, the omission in AAVE is not considered 'ungrammatical', for there are numerous native speakers who do so. There is no 'the etiquette of linguistics' that language users must follow. If anything, modern linguistics supports the omission of the Oxford comma according to the data I presented in C1. (4) My opponent also claimed that the Oxford comma is supported by 'Many of the widely accepted experts', a weasel word, and even if had presented real experts, the argument remains a false appeal to authority. Finally, my opponent cited the Oxford Companion to the English Language, which states, 'Commas are used to separate items in a list or sequence.' That this refutes the omission of the Oxford comma is a non-sequitur: 'Pens are used to write words' does not imply 'Pens are used to write all words', just as this sentence does not imply 'Commas are used to separate all items'. In fact, the Companion itself acknowledges that the Oxford comma is 'sometimes superfluous' and 'controveresial'. (6) R4) Reasons why you should use it 1-3) A series of bare assertions which I've shown to be false in C1, C2 and R1 respectively. 4) Surely, if consistency were the issue, we should eliminate 'and'? 5) Removing the comma only shortens the pause between the penultimate item and the conjunction, not with the last item. Finally, my opponent cites an online survey. This is invalid because self-assessment of one's grammar is by no means an accurate measure of language proficiency, because online surveys suffer from biased demographics and the possibility of manipulation and because correlation does not imply causation - punctuation is not related to 'grammar' in the sense of morphosyntactic accuracy; these stats do not indicate that the comma is 'grammatical'. R5) Facts My opponent presents two historical texts that use the Oxford comma, but both are historical. They have no bearing on present language conventions. 100 years ago, 'today' was spelt as 'to-day'. Orthographic conventions were so shaky in Shakespeare's time, in fact, that he had six ways of spelling his own name. (5) C1) Descriptivism My opponent has made a straw man argument. I have never claimed that omitting it is grammatically superior. However, under the premise of descriptivism, there is no reason to impose a ban on practice with widespread use in writing. What is right depends on whether the usage is widespread, not on perceived superiority. With my overwhelming evidence that points to the prevalence of the Oxford comma, it automatically follows from decriptivism that omitting the comma is not wrong. C2) Prosody My opponent has made no real counter-arguments apart from a bare assertion under his fourth heading. C3) Practicality and C4) Readability I have addressed ambiguity above. (1) The Sentence in Written English, Huddleston, R. D. (2) Phonology for Dummies, Katz, F. (3) Their respective guides (4) The Study of Language, Yule, G. (5) http://politicworm.com... (6) Oxford Companion to the English Language