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Quod erat demonstrandum

Definition

Latin for "which was to be demonstrated."  Often abbreviated as Q.E.D., the statement may appear at the conclusion of a text to signify that the author's overall argument has just been proven.

Illustrative caselaw

See, e.g. Stupak-Thrall v. U.S., 89 F.3d 1269, 1299 (6th Cir. 1996).

See also

 

"After an exhaustive discussion of the arguments for and against gun control, Justice Breyer arrives at his interest-balanced answer: because handgun violence is a problem, because the law is limited to an urban area, and because there were somewhat similar restrictions in the founding period (a false proposition that we have already discussed), the interest-balancing inquiry results in the constitutionality of the handgun ban. QED."