For a genuine contradictory pair there are only two possibilities:
Case 1: The first statement is true and the second false.
Case 2: The first is false and the second true.
They cannot both be true or both false.
For the same specified integer, 'This integer is even' and 'This integer is not even' satisfy this test.
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The truth test
Contradiction and the Eight Conditions
For a genuine contradictory pair there are only two possibilities:
Case 1: The first statement is true and the second false.
Case 2: The first is false and the second true.
They cannot both be true or both false.
For the same specified integer, 'This integer is even' and 'This integer is not even' satisfy this test.