But these two sets of possible alternatives are different . . . Thus one could have a test of H without having a test of its contrapositive.
22.
In logic, the "'contrapositive "'of a conditional statement is formed by negating both terms and reversing the direction of inference.
23.
The inverse and the converse of a conditional are logically equivalent to each other, just as the conditional and its contrapositive are logically equivalent to each other.
24.
As a corollary ( i . e ., its contrapositive ), the compactness theorem says that every unsatisfiable first-order theory has a finite unsatisfiable subset.
25.
That is, a regular curve with nonzero torsion must have nonzero curvature . ( This is just the contrapositive of the fact that zero curvature implies zero torsion .)
26.
The process of the logical equivalence of a statement and its contrapositive as defined in traditional class logic is " not " one of the axioms of propositional logic.
27.
Now, the law says that statement is identical to the contrapositive " " If something is not a mammal, then it is not a bat " ."
28.
Therefore, the square of a rational non-integer is always a non-integer; by contrapositive, the square root of an integer is always either another integer, or irrational.
29.
They accept the possibility of motion and apply modus tollens ( contrapositive ) to Zeno's argument to reach the conclusion that either motion is not a supertask or not all supertasks are impossible.
30.
One way of proving a statement about the objects of " S " is to assume the existence of a counterexample and deduce a contradiction, thereby proving the contrapositive of the original statement.
