sufficiency (logic)

In logic, sufficiency defines a relationship between two logical statements in which knowing that one statement is true is enough to conclude that the other statement is true as well. If we say that “p is sufficient for q,” we mean that knowing that statement p is true is enough to say that statement q is, too. Note, however, that q can be true even if p is false. We can write this as an implication: pq.

As an example, consider the statement “Being an ape is sufficient for being a mammal.” In other words being an ape implies being a mammal, but something can be a mammal without being an ape, am.

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