Section 29

This section was really just a continuation of section 28, and most of the logic is very similar. I think that once you figure out creative ways to make a set countable, then the rest is just (very loose) intuition, and it's not really to bad. These proofs are kind of tough though, because their structures don't seem as concrete as the ones before them, and therefore they are harder to formulate.

The main thing I didn't understand at all was remark 25.9. I did not understand at all how f was injective but not surjective, and also how im(f) was countably infinite. I really need to see it worked out in order to understand this.

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