Military/espionage meanings are specialized and like any specialized meanings, they don't have to correspond to everyday meanings, or even to scientific ones. I'm guessing intelligence comes in some kind of "level."
I've heard the term "raw" intelligence, for example. Perhaps these are little bits and pieces that are acquired through disparate means. I can imagine that the great bulk of this unprocessed intelligence must be almost useless.
There could be various levels of processing of this intelligence. Ideally, you want a clear picture of what someone else is doing and thinking. This raw intelligence is a bunch of pieces of a jigsaw puzzle - except in a jigsaw puzzle, you know what you're trying to piece together. But intelligence services can only postulate what the picture looks like and then see how closely they can get the pieces they have to fit into something that looks like that. The raw information must be very spotty. I doubt the situation today is much like the situation just prior to World War II, when the Brits were intercepting Japanese diplomatic messages and we knew practically everything they were doing and thinking.
But it must be worse than this; that is, it's worse than just that some key pieces are missing - the person whose activities you are attempting to discern knows you are doing this and puts out false pieces. Also, the other people whom you rely on for intelligence put out false clues. And very possibly one's colleagues put out false clues.
You take what you have. You try to make little pictures from it. That's one level of processing. Then you try to fit the little pictures into successively bigger pictures. But all of this must be flavored by what you think the end picture already looks like. (I say "must," but that's only a guess.)
Anyway, I'm not sure of the relationship between the uses of the word intelligence in espionage vs mental capacity.
k
