We often attribute 'understanding' and other cognitive predicates by metaphor and analogy to cars, adding machines, and other artifacts, but nothing is proved by such attributions.
I want to block some common misunderstandings about "understanding": In many of these discussions one finds a lot of fancy footwork about the word "understanding."
There are clear cases in which "understanding" literally applies and clear cases in which it does not apply; and these two sorts of cases are all I need for this argument.