When I studied physics as a freshman in college, we had some calculus but not much in the way of linear algebra. Therefore, quantum was taught using wave functions and simple partial differential equations which were generally solved by separating variables (factoring). I asked my professor if he thought of an electron as a particle or as a solution to a differential equation and he told me to start thinking of it as a solution.  End of physics for me (I actually very much liked this professor - I just thought the subject was too untethered to reality compared to my high school experience).<br><br>Now, two times through this book and one time through the lectures on line and back to my college math books to bone up on Hermite polynomials and ladder operators, I finally think I get some of this.<br><br>When I say I get it, I can now start with a problem and work out the answer without looking back at the text or at the video.<br><br>This is abstract but ultimately it is not hard. I have read the other two "minimum" books and they are really harder but somehow easier to understand.  But when I try to work through those problems, I have much more math to get through.<br><br>Anyone who wants to get some insight into quantum should wok through the book, paper and pencil in hand. You will be rewarded.