"There are these four ways of answering questions. Which four? There are questions that should be answered categorically [straightforwardly yes, no, this, that]. There are questions that should be answered with an analytical (qualified) answer [defining or redefining the terms]. There are questions that should be answered with a counter-question. There are questions that should be put aside. These are the four ways of answering questions."
First the categorical answer, then the qualified, third, the type to be counter-questioned, & fourth, the one to be set aside. Any monk who knows which is which, in line with the Dhamma, is said to be skilled in the four types of questions: hard to overcome, hard to beat, profound, hard to defeat. He knows what's worthwhile & what's not, proficient in (recognizing) both, he rejects the worthless, grasps the worthwhile. He's called one who has broken through to what's worthwhile, prudent, wise.