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

Famous quotes containing the words square of, square and/or opposition:

    After the planet becomes theirs, many millions of years will have to pass before a beetle particularly loved by God, at the end of its calculations will find written on a sheet of paper in letters of fire that energy is equal to the mass multiplied by the square of the velocity of light. The new kings of the world will live tranquilly for a long time, confining themselves to devouring each other and being parasites among each other on a cottage industry scale.
    Primo Levi (1919–1987)

    If the physicians had not their cassocks and their mules, if the doctors had not their square caps and their robes four times too wide, they would never had duped the world, which cannot resist so original an appearance.
    Blaise Pascal (1623–1662)

    At times it seems that the media have become the mainstream culture in children’s lives. Parents have become the alternative. Americans once expected parents to raise their children in accordance with the dominant cultural messages. Today they are expected to raise their children in opposition to it.
    Ellen Goodman (20th century)