I just finished reading A Theory of Fun for Game Design by Raph Koster. Despite being 256 pages long, it’s a short, easy read. Raph illustrates his ideas with single-drawing cartoons on nearly half the pages, and the layout does not fear whitespace.
In short, Raph claims that creatures (including higher-order animals) are wired to play games as practice for the real world. As humans, we excel at this, and that’s why we find them fun. We also use our pattern-recognition skills to analyze and reduce games to their simplest forms once we grok what they’re about.
It’s a good basis for understanding how and why we play games, and Raph’s writing is clear and accessible throughout. While he mostly talks about video and computer games, he’s also played many tabletop games, and you should be able to take his ideas and apply them to just about any sort of game.
If you’re a game designer, would like to be one, or just enjoy games, be sure to check it out.