A bare assertion; an “ipse dixit.”

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1804.  If the Democrats’ say so could make Mr. Jefferson a Christian, he would long ago have been one of the greatest in our country.—The Balance, Oct. 30, p. 347/3 (Hudson, N.Y.). (Italics in the original.)

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1844.  How could they know that they had handled and hefted as many of the leaves as said [Joseph] Smith translated? Certainly on no other grounds than his “say so,” which is good for nothing.—D. P. Kidder, ‘Mormonism and the Mormons,’ p. 53 (N.Y.).

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1852.  Your own say-so will be enough for any honest white man.—James Weir, ‘Simon Kenton,’ p. 93 (Phila.).

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1862.  Have we had any such experience [of these gentlemen’s wisdom] that we can take it upon their bare say-so against the testimony of [experts]?—Mr. William P. Fessenden of Maine, U.S. Senate, March 27: Cong. Globe, p. 1400/1.

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