This is a bit late, but this comment has a bit of coverage thanks to Google.
The thing about probability of events, is that it is intrinsically linked to the observer. There’s no probability in the physical phenomena itself (I’m not quite advanced in my studies of quantum mechanics as of yet, to comment on the uncertainty principle, but that again is related to the observer).
Again, this idea has been stated several times in the sequences. That’s what it’s meant by unusual thing.
Somewhat relevant: I’ve recently taken an algebra course which covered both abstract algebra and linear algebra (those the fields aren’t disjoint though), and I’ve really enjoy this book by Saunders and Birkhoff : Algebra.
It covers abstract algebra in a very thorough, theoretical fashion, with plenty of exercises. It has chapters of Vector Spaces and Matrices, and builds those concepts from the ground up (beginning with the concept of a free module).
I’m studying CS, so obviously this book is miles ahead of the curriculum (the quality of the uni is quite laughable as well, but well) but I set a mental reminder to have another go at this book once I’ll have more spare time.