"Aren't I is fine, and as you say, "am I not" is pompous.

It's just a quirk of English. I might also add, to be provocative, that if it's commonly accepted it's grammatical! Grammar was made for man and not man for grammar.

stick to correctness, and leave "aren't I" for classroom/bar chat.

PS: "Am I not?" doesn't sound pompous to me, especially when in writing.

According to the 4th edition of "A Practical English Grammar", by A.J. Thomson and A.V. Martinet.
Page 116 of my copy (section 113), entitled "be as an auxiliary verb"
says that "am I not?" and "aren't I?" are completely equivalent.
Therefore, they're both grammatically correct.
I agree with most of the colleagues above: "am I not" sounds a tad highfalutin.

All are perfectly normal and are examples of correct usage.

My findings may be os use/interest to you.



1 - http://www.xrefer.com/entry.jsp?xrefid=591595&secid=.4.-#s.4...

About The New Fowler's Modern English Usage from Oxford University Press


be


4 Paradigmatic forms. No special difficulties arise with the normal indicative forms, am, is, are; past tense was, were; participles being, been. In speech, reduced forms of am, is, and are ('m, 's, 're) are freely used, and these often make their way into written English (I'm = I am, she's = she is, they're = they are), though such reduction is impossible after a preceding sibilant consonant (the moss is green, not *the moss's green) or affricate (the church is cold, not *the church's cold). In constructions of the type am, is, are + not, the word not in unabbreviated form is written separately whether or not the first element is contracted: am not/'m not, is not/'s not, are not/'re not. When the negative itself is contracted, it combines with the full form of the preceding element: thus isn't, aren't, wasn't, and weren't (not 'sn't, 'ren't, etc.). There are two anomalous forms: ain't (see the article on it at its alphabetical place in this book); and aren't when used as a tag-question in the form aren't I?. The expected reduced form of am I not? is amn't I?, as it is in many modes of speech in Scotland and Ireland but not in standard southern British English. It is possible (as a correspondent has pointed out to me) that, when followed by n't, am behaves exactly like can and shall, losing its final consonant and (in standard English) lengthening its vowel. The expected spelling would be an't, but in those forms of English which lose pre-consonantal r the short form of am not merges with that of are not in both speech and spelling.Whatever the explanation, aren't I? is a regular and natural tag-question in standard British English. An American scholar, John Algeo, said recently (1995) that 'the expression is now in widespread use in America with no consciousness of a British origin', though he acknowledges that it might indeed be of British origin.In informal contexts, the reduced forms i'n't and i'nt were once (18c.) commonly written for isn't, is not: the evidence is to be found in the Oxford English Dictionary. One hears, or one imagines one hears, some people saying /Int/ to this day for isn't in such a sentence as It isn't fair /It Int fe /. But this pronunciation, and also the vulgarism innit? /'InIt/ for isn't it (see Oxford English Dictionary 2), both lie outside the realm of standard English.The charming forms wast (2nd person singular past tense) and wert (2nd person singular past subjunctive, and also, since the 16c., past indicative) are now used only as archaisms. Examples: Art thou the first man that was borne? or wast thou made before the hilles?-Job 15: 7; I would thou wert cold or hot-Rev. 3: 15; Thou wer't borne a foole- Shakespeare, The Winter's Tale 1611; Oh, wert thou in the cauld blast-Burns, a1796; Hail to thee, blithe spirit! Bird thou never wert-Shelley, 1820.


2 - http://www.learnenglish.org.uk/grammar/archive/short_answers...



Short answers 4

more short answers Back to Index
1. What's the difference between am I and aren't I?The verb to be is the present simple is formed as follows:I am / I'm not / Am I? / Yes, I am / No, I'm not. · Am I the lucky one? · Am I happy? Yes I am. However, in question tags, the form for I am is aren't I. · I'm next, aren't I? · I'm the one you're after, aren't I? Note that the form for I'm not in question tags is am I. · I'm not keeping you, am I? · I'm not doing it for the money, am I?

I remember hearing or reading somewhere that the original (or at least earlier) contraction for am i not was ain't I. When the grammar police went after ain't meaning isn't, its proper usage in the first person singular was caught up in the bust, and people started saying aren't I (which was even more incorrect but was gc~before there was pc there was gc). But perhaps this is just some creative jive from some fanciful ex-prof of mine.