In contrast, D&D rules don’t connect to other topics in any strong way.
I doubt that. Before I had finished the paragraph, things that came to mind included board games, what underlying skills transfer between different board games and RPGs (from empirical evidence, they exists and are large), what the appeal of roleplaying a fictional character it is, which different desires roleplaying versus powergaming satisfy, what makes a character attractive to roleplay, what makes a roleplay performance fun, what makes a D&D setting enticing, how to create an enticing D&D setting, whether the most fun is had when the DM does a good job of almost killing the characters (as someone told me), and more. These, of course, give hooks to combinatorial game theory, personality, improv acting, fiction writing, and fun theory. With the possible exception of personality (though it’s a small leap to MUDs and the Bartle 4, so probably not an exception), all of these play quite important roles in D&D.
I suppose I’m muddying it a bit since some of those things are connected to D&D but not directly to D&D rules, though your original post simply mentioned D&D.
Knowledge is connected enough that I’d be quite impressed if anyone could find (or, heck, invent) a topic which fails criterion 4.
Even D&D rules connect to the general problem of creating games which are understandable and playable and the problem of creating reasonable facsimiles of reality—these contrast in an interesting way with the scientific problem of creating computationally-tractable models which predict reality, for example.
I doubt that. Before I had finished the paragraph, things that came to mind included board games, what underlying skills transfer between different board games and RPGs (from empirical evidence, they exists and are large), what the appeal of roleplaying a fictional character it is, which different desires roleplaying versus powergaming satisfy, what makes a character attractive to roleplay, what makes a roleplay performance fun, what makes a D&D setting enticing, how to create an enticing D&D setting, whether the most fun is had when the DM does a good job of almost killing the characters (as someone told me), and more. These, of course, give hooks to combinatorial game theory, personality, improv acting, fiction writing, and fun theory. With the possible exception of personality (though it’s a small leap to MUDs and the Bartle 4, so probably not an exception), all of these play quite important roles in D&D.
I suppose I’m muddying it a bit since some of those things are connected to D&D but not directly to D&D rules, though your original post simply mentioned D&D.
Knowledge is connected enough that I’d be quite impressed if anyone could find (or, heck, invent) a topic which fails criterion 4.
Even D&D rules connect to the general problem of creating games which are understandable and playable and the problem of creating reasonable facsimiles of reality—these contrast in an interesting way with the scientific problem of creating computationally-tractable models which predict reality, for example.