Who or what is IMO? I can't tell you why they like it, I can only tell you why I like it.
It remains my best model of how the brain works, he explains this by using an anthill as an example.
Then there is the palindrome dialog called Crab Canon, 2 pages of dialog which reads the same forwards and BACKWARDS.
This book is full of information presented in a very creative fashion. I Would recommend reading it slowly, digesting each chapter before starting the next. If you have interest in strange loops, this book is required reading.