in logic, are of four kinds, called A, E, I, O. “A” is a universal affirmative, and “E” a universal negative; “I” a particular affirmative, and “O” a particular negative.
Asserit A, negat E, verum generaliter ambo I Asserit I, negat O, sed particulariter ambo.
A asserts and E denies some universal proposition; I asserts and O denies, but with particular precision.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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