Someone who is so incredibly stupid that only an obscure analogy could describe their low level IQ. Just as a wet match in a dark room is the antithesis of light, an incredibly stupid person is the antithesis of an intellectual.
something will never work. When the concept is doubtful, it is a match in the dust. This is because when I lit match hits dust, it goes out and extinguishes. So when something is a match in the dust, it will never work.