Section 26 due Nov 9

1. This section is nice. It's like I'm in grade school again for the most part. Associativity of compositions of functions is simple. I'm still not super solid on the intuition behind injective and surjective yet but that's probably because I haven't done the section 25 exercises yet.

2. I'm just wondering like... how do these things come about? All of these mathematical ideas? And also, how many of the ways we do things are simply arbitrary? Could there be some other mathematical system? Are there things about ours that hold us back from understanding things about the universe? I'm not really sure if any of these questions make any sense but I just read all these definitions and theorems in the books and I wonder, like what is the real foundational truth underneath them? So much of it is like intellectual scaffolding that we've constructed just to understand a make sense of the world, but what's underneath that? Maybe I'm asking the wrong questions but it's interesting to think about.