This was incredibly good!
I loved how the characters philosophised about ethics, psychology and science using the magic system. The magic system is so thoroughly thought through and so well established. Most of this book is basically explaining the science of magic and theorising using it. I love it when a book uses its unique, fantastical, elements to basically just philosophies about things in the real world and this book does it so well! Everything is so thoughtful!
The characters are incredibly intriguing and interesting. Perhaps not quite likable, which is a bold choice considering that this book is character-driven, but the characters are so unique and interesting that it just works magnificently. 
Just a glorious read!