I would consider “black magic” to be something that works reliably due to some specific and idiosyncratic property of the environment that it operates within. B

I would consider “black magic” to be something that works reliably due to some specific and idiosyncratic property of the environment that it operates within. Basically, something that is exceptionally tightly coupled. I think the novel FPGA solutions that genetic algorithms can create fall into this category; they often didn’t work on different boards, or even when the same board was plugged into a different power supply because the solution was overfit. “A Story About Magic” is black magic in action. http://catb.org/jargon/html/magic-story.html http://catb.org/jargon/html/magic-story.html “The Story of Mel” is not black magic even though no one else understood his program. http://www.catb.org/jargon/html/story-of-mel.html http://www.catb.org/jargon/html/story-of-mel.html