[foldr]

Yes I'm aware that you need an evaluation heuristic. My point is that you don't need a particularly good one to be able to beat an average intelligent human at chess. (After all, most humans don't have very sophisticated chess position evaluation heuristics, and they are able to examine vastly less of the search space than a computer.) Beating Kasparov is another matter, of course.

Here's an example of a simple chess engine that is good enough to beat amateur human players at least some of the time:

https://news.ycombinator.com/item?id=8133125

[gaius]

Or even https://en.wikipedia.org/wiki/1K_ZX_Chess