H.L. Mencken (18801956). The American Language. 1921.
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was applied, and so there arose such forms as minum and eowrum (=mine and yours), from min and eower (=my and your).72 Meanwhile, the original simple genitive, now become youre, also survived, and so the literature of the fourteenth century shows the three forms flourishing side by side: youre, youres and youren. All of them are in Chaucer.
Thus, yourn, hern, hisn, ourn and theirn, whatever their present offense to grammarians, are of a genealogy quite as respectable as that of yours, hers, his, ours and theirs. Both forms represent a doubling of inflections, and hence grammatical debasement. On the side of the yours-form is the standard usage of the past five hundred years, but on the side of the yourn-form there is no little force of analogy and logic, as appears on turning to mine and thine. In Anglo-Saxon, as we have seen, my was min; in the same way thy was thin. During the decadence of the language the final n was dropped in both cases before nounsthat is, in the conjoint formbut it was retained in the absolute form. This usage survives to our own day. One says my book, but the book is mine;thy faith, but I am thine.73 Also, one says no matter, but I have none. Without question this retention of the n in these pronouns had something to do with the appearance of the n-declension in the treatment of your, her, his and our, and, after their had displaced here in the third person plural, in their. And equally without question it supports the vulgar American usage today.74 What that usage shows is simply the strong popular tendency to make language as simple and as regular as possibleto abolish subtleties and exceptions. The difference between his book and the book is hisn is exactly that between my and mine, thy and thine, in the examples just given. Perhaps it would have been better, says Bradley, if the literary language had accepted hisn, but from some cause it did not do so.75
As for the addition of s to you in the nominative and objective
Note 72.Cf. Sweet: A New English Grammar, pt. i, p. 344, 1096. [back]
Note 73. Before a noun beginning with a vowel thine and mine are commonly substituted for thy and my, as in thine eyes and mine infirmity. But this is solely for the sake of euphony. There is no compensatory use of my and thy in the absolute. [back]
Note 74. I am not forgetting, of course, the possible aid of his own, her own, etc. [back]