Only when the manas gives rise to doubt is it possible to discover the truth

When you say in your mind that none of this is "I," you should ask yourself why—ask several whys. If you cannot explain it clearly, continue your contemplative practice (vipaśyanā-caryā). You must ask and answer yourself repeatedly; only in this way can you have evidence, and with conclusive evidence can you discover the facts and discover the truth. If you truly have doubts, it means the manas has generated doubt—He does not understand and wants to understand. This is a good thing. What is to be feared is having no doubts, for then you are still very far from seeing the path.