We are working with TSK Ex. 1-3 as though they were three parts of one exercise. This seems to me legitimate, but I want to acknowledge that it goes against what is said in the text, which suggests spending days (or weeks!) building up the image used in Exercise 1 before even starting to do the exploration suggested there. It would be great to proceed in this way, and if anyone is doing it, I would love to hear about your experience.
My main point in this post is to focus on the commentary to TSK Ex. 3. Rinpoche points out that the usual model is that consciousness (sentience) arises through the joint operation of lots of non-sentient ‘things’, such as cells, neurons, electrical impulses, etc. He suggests that doing the exercises (1-3, and also the others that come later, I think) can clarify an alternative view, in which knowing is primary, and the particular ‘unknowing’ things such as atoms that we encounter in the exercises ‘derive’ from this more fundamental knowing. It would be useful to keep this possibility in mind as you do the exercises.
Notice how this idea relates to “given together” model of LOK Ex. 5, in which we see the self as part of each experience rather than as the owner of experience. In doing that exercise, there is a knowing going on, but the suggestion is that this knowing can be an element of the entire situation that one investigates.
Jack