Scott

Selfish is doing what is in your Best Interest, not doing what you want at everybody else's expense. Popular use of the word has confused it with Greedy, Foolishly Demanding even Stupid. So doing what is in your best interest is a virtue not a negative. Deciding what is in your best interest is not always easy. But once you have decided, it is the only course to take.
The Gene has a different time frame than us mere humans. The Gene Pool has experimented for many hundreds of millions of years. Genes may try being lazy or stupid or greedy in all that time, but the Genes that are passed on have chosen what is in their best interest or the "Selfish" choice. The Genes that are greedy or lazy find it harder and harder to reproduce and do not continue.
I loved this book. The change of narrator between Richard and Lalla was at appropriate and necessary points. The cadence and tone were good. The book kept me (a layman) interested till the end.
The fact that you have read this far into a review on a book with this title makes me believe you are a thinker. Listen to this book to clarify your thinking.
Enjoy!