Double Comparative in English Grammar

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The double comparative is the use of both more (or less) and the suffix -er to indicate the comparative form of an adjective or adverb.

In present-day standard English, double comparatives (such as "more easier") are almost universally regarded as usage errors, though the construction is still heard in certain dialects.

Examples

Marjorie Bartholomew Paradis: Some-a people think I'm more dumber than them because I don't talk so good, but they only know one language and me--I speak-a two.

Ron Rash: I was more tireder than ever I'd been in my life, wore down beyond weariness.

Mordecai Richler: But the only thing I got to tell you, if you take a dog and kick him around he's got to be alert, he's got to be more sharper than you. Well, we've been kicked around for two thousand years. We're not more smarter, we're more alert.

Kent to King Lear, King Lear: Repose you there; while I to this hard house—More harder than the stones whereof 'tis raised.

The Taboo Against This Belt-and-Suspenders Usage

Kenneth G. Wilson: Double comparison is taboo in Standard English except for fun: Your cooking is more tastier than my mother's. I can see more better with my new glasses. These illustrate the classic double comparative, with the periphrastic more or most used to intensify an adjective or adverb already inflected for the comparative or superlative. A belt-and-suspenders usage, this is a once-Standard but now unacceptable construction (like the double negative) that illustrates yet again our penchant for hyperbole. Shakespeare (the most unkindest cut of all) and other Renaissance writers used double comparison to add vigor, enthusiasm, and emphasis, and so do young children and other unwary speakers of Nonstandard English today.

The Double Comparative in Early Modern English

Thomas Pyles and John Algeo: As was true in earlier times also, a good many instances of double comparisons like more fitter, more better, more fairer, most worst, most stillest, and (probably the best-known example) most unkindest occur in early Modern English. The general rule was that comparison could be made with the ending or with the modifying word or, for emphasis, both.

C.M. Millward: More and most were historically not comparative markers, but intensifiers (as they still are in such expressions as a most enjoyable evening). In EMnE [Early Modern English], this intensifying function was felt much more strongly; hence writers did not find it ungrammatical or pleonastic to use both a comparative adverb and -er or -est with the same adjective. Examples from Shakespeare include in the calmest and most stillest night and against the envy of less happier lands.