Square of Opposition

In the system of Aristotelian logic, the square of opposition is a diagram representing the different ways in which each of the four propositions of the system is logically related ('opposed') to each of the others. The system is also useful in the analysis of syllogistic logic, serving to identify the allowed logical conversions from one type to another.

Read more about Square Of Opposition:  Summary, The Problem of Existential Import, Modern Squares of Opposition, Logical Hexagons and Other Bi-simplexes

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