Do you practice careful and serious reading? This is the ultimate question I have come to ask when someone claims to have read the book and clearly I find out s(he) meant to say "eyes went" instead of "mind went" through the content of the book. There is a difference between "becoming familiar" and "digesting" a topic.
When you carefully read a book you take notes. I personally do not like to highlight books as the highlighters I have seen so far as of December 2014 will literally ruin the book. I think taking notes not only help with deep understanding of the content but ultimately it becomes a great summary for further "quick reference".
When you seriously read a book you know what you disagree and agree upon, you are not in a sofa distracted by familiar sounds. You are in a quite space, fully concentrated in receiving a message, processing the message and coming up with your own conclusions, questions and ultimately must importantly answers to the unknown which now suddenly becomes part of your personal wisdom.
It is discouraging to sustain a debate around a book content when there is not careful and serious reading. In my opinion "reading" when it comes to a specific subject matter means "studying" and of course you can only claim you have studied a subject if you have carefully and seriously read the related material. Seeing a book is not the same as looking into a book. Listening to an audio book content is not the same as hearing it.