contrapositive

THE X FACTOR Is this man serious?

MR. RUSSERT: How many Iraqi security forces do we need fully trained and capable of fighting insurgents?

SEC'Y RUMSFELD: Well, the answer to that question is not complicated. We need as many as are needed. If you have an insurgency that's this level, you'll need X. If you have an insurgency that's that level, you'll need X-plus. And if you have an insurgency that's quite low, you'll need X-minus.

Glad we got that clear.