The fly ball is up. You put your mitt out and... you either caught it or you didn't. Let's say you caught it. You know you did. How do you know?
Maybe you know because of a certain sound? Maybe you know because the mitt tugs at your hand in a particular way when a ball lands in it? Maybe you know because you feel some pressure and resistance in your arm? Or something else? Maybe some combination of these things?
Let's say that you know principally because of how the mitt tugs at your hand. The mitt doesn't tug in that hard-to-define way unless you've caught the ball. If it does tug that way, you think you've caught the ball; if it doesn't you don't. Yet here are two things you might not know: (1.) that the mitt tugged at your hand in that particular way (as opposed to some other way, or not at all), (2.) that if the mitt tugs in that way, you've caught the fly. In fact, you might well deny (1) and (2). If inference requires accepting the premises, you don't reach the judgment that you've caught the ball by inference.
Let's say then that you're attuned to some fact or contingency, if you make judgments in a way that shows sensitivity to that fact or contingency -- judgments that may count as knowledge -- but without necessarily being able to reach an accurate judgment about the fact or contingency to which you are sensitive.
Other examples: I might be attuned to the lift of the interior portion of the eyebrows that often expresses sadness, and know on that basis that someone is sad, and be quite ignorant or mistaken about the position of the eyebrows. I might be attuned to the echoic properties of my footfalls in judging how far away a wall is that I cannot see, yet think I'm judging the distance of the wall on the basis of air pressure on my face. (For an extended discussion of this last example, see my paper on human echolocation.)
Surely attunement is an interesting concept. I'll talk more about a couple things I'd like to do with the idea of attunement in the philosophy of perception and in introspection in a future post.
There are connections here to the epistemological literature on information and tracking, but most epistemologists (that I'm aware of) who talk about tracking and information don't draw as clean a distinction as I'd like between responsiveness to facts that involves judgment, belief, and knowledge, and responsiveness that is non-judgmental.
There are also connections to the philosophy of mind literature and cognitive psychology literature on subpersonal information processing and inference, but I'd prefer to avoid the idea of inference here. One's judgments can be responsive to something without representing that thing in the sense of traditional cognitive science, as long as they are contingent on that thing, by whatever mechanism.