Faith
In Buddhism, faith has nothing to do with anything outside of ourselves. It does not necessarily have to do with something supernatural or esoteric. In a sense, it's faith in our own true nature. It's faith in a sense that I can be willing to let go of that certainty. And if I am willing to have the courage to meet the moment, something authentic, real and natural can emerge. Something that I may not understand. Something that may look nothing like I may expect. But there's a faith that if I just continue on, true nature will reveal itself. It's already present in all things. In the sense, you can say it's faith that using great question and great courage is enough. Not needing the certainty of an answer, but trusting the question.