I can’t understand why the phrase “for the life of me” isn’t “for the life of mine.” Mine is a possessive pronoun, not me. You don’t say, “Some friends of me.” You say, “Some friends of mine” OR “Some of my friends.” Me doesn’t convey—grammatically—possession, and it is neither a possessive adjective nor a possessive pronoun. Why, then, is the phrase “for the life of me”? What is the origin of the use of me in this way? Is there any historical usage of a possessive me, or is this simply an ungrammatical phrase i.e. an idiomatic phrase?
I understand your difficulty. The difference is quite subtle. In fact it is so subtle that I haven't yet seen how to formalise it. In the mean time, here are some examples to confuse you further.
For this life of mine. (correct) - For this life of me. (incorrect)
For the life of mine. (incorrect) - For the life of me. (correct)
For the sake of me. (correct) - For the sake of mine. (incorrect)
For the book of me (incorrect) - For the book of mine (correct)
For the story of me (correct) - For the story of mine (incorrect)
▶ not for the life of you
expresses the impossibilty of your doing, understanding “something”, etc UK, 1809
I could not, for the life of me, recall the time of his vanishing. — The Observer, 8 October 2000
for the life of me TFD
at all; even one little bit. (Used with a negative.)
For the life of me, I can't figure this out. I can't for the life of me climb up a mountain.
Why me and not mine? I am not a linguist but it appears to just be idiomatic.
One part of me wants to wait until I have an in-depth etymology of the phrase before answering. But the other part of mine is ungrammatical.
Really, if you think about it, you'll see that it's pretty common to see "of me" (and "of you", "of her", etc.) being possessive, with the "of mine" version being ungrammatical:
- The death of me
- The end of me
- The best of me
- The worst of me
- The rest of me
- One side of me
- One half of me
- One piece of me
(Some of these can be rewritten as e.g. "my best".)
The OED gives a pretty good explanation of how this sense came about:
Expressing possession and being possessed.
E.g. 'the owner of the house', 'the house of the owner'. Generally regarded as one of the central uses of the word. Formerly expressed by the genitive case, and still to some extent by the genitive of nouns (especially proper names) and possessive adjectives (with transposition of order). The use of of began in Old English with senses 33, 34, expressing origin. After the Norman Conquest the example of the French de, which had taken the place of the Latin genitive, caused the gradual extension of of to all uses in which Old English had the genitive; the purely possessive sense was the last to be so affected, and it is that in which the genitive or 'possessive' case is still chiefly used. Thus, we say the King's English, in preference to the English of the King; but the King of England in preference to England's King, which is not natural or ordinary prose English.
The earliest example of the single possessive indicating ownership is the Ormulum's "Þe wlite off enngle kinde" ("the beauty of angel kind").
And it also has this other definition for of with its earliest examples dating back to Middle English:
Followed by a noun in the genitive case or a possessive pronoun.
Originally partitive, but subsequently used instead of the simple possessive (of the possessor or author) where this would be awkward or ambiguous, or as equivalent to an appositive phrase; e.g. this son of mine = this my son; a dog of John's = a dog which is John's, a dog belonging to John. The early examples are capable of explanation as partitive, but in later use this is often not possible, and the construction may now be viewed as appositional (see further O. Jespersen On Some Disputed Points in English Grammar (S.P.E. Tract No. XXV, 1926)).