What is called thinking?

In this lecture course, Heidegger defines thinking as a paying heed to the thought-provoking. He observes that “we are not yet capable of thinking,” and suggests that what most provokes us to thought is this recognition that we are still not thinking. It is not the kind of book that can be read and then summarized after the fact. Heidegger lets us question, but we have to find the answer for ourselves. In order to think, I must get on the path to thinking. Thinking isn’t something available to me, let alone something I can share.