My first computer science course was a life-changing moment for me. I was two years deep into general-ed, I was trying to manage my mother's alcoholism that I had just started to understand, and my girlfriend and best friend wanted me to move away to state University with her. I read that Java book start to finish, every chapter, and eventually realized the potential that computers can bring the world.

Anecdote aside, there's a difference between reading something and understanding something. My friend who is really in tune with the nature of the subject, is also spending an incredible amount of time surrounding it.