I bought The Ideas Behind the Chess Openings Link although I bought an older 1970s book rather than the one in the link.
It’s really a great book, my version is in the older chess notation and I set up a board on my bed to play through all of the openings. I’m now using D4 as my primary opening.
I’m thinking of buying his end game and middle game books as well. Are the equally worthwhile to add to my collection? I play primarily online, but I also like to play in coffeehouses.
Aside from errors in analysis (inevitable, but I know a number of later editions failed to correct them), I find the format of Fine’s Basic Chess Endings (namely, move sequences appearing right in the paragraph [e.g., 1… Bxh2 2. g3 h5 3. Ke2 h4 4. gh, etc.], makes it rather unreadable. Batsford Chess Endings, by Speelman, Wade and Tisdall, is, to me, is a much better one-volume endgame text. I will add that I don’t know much about any chess books aside from Kasparov’s (which I haven’t read, either, but I know about them) that have come along in the last fifteen years or so.