Humans evolved to have a variety of senses—smell, sight, touch, etc.—that provide information about the world around us.
If I asked you to name some ways of knowing, you might mention a few familiar ones. You can come to know something by observation using your senses: you can come to know that it’s dark by looking out of your window. You can come to know something by testimony: you can come to know that there’s a sale on at Barney’s right now by hearing your friend tell you just that. You can also come to know something by working it out in your head: you can figure out that 68 + 57 is 125 just by adding 68 and 57.
In each of these cases, you’re coming to know something that was already a matter of fact: it was dark before you knew it, the sale ran before you knew it, and 68 + 57 has been 125 since at least the dawn of time. In other words, each of these cases of coming to know something involved learning: gaining knowledge of a fact that was a fact even before you knew about it.
But there’s another way of coming to know something, one I bet that you wouldn’t think of at first. This way of knowing doesn’t involve observing things, gaining testimony, or calculating anything. And it doesn’t involve learning: coming to know in this way doesn’t involve coming to know a pre-existing fact. For these two reasons, it’s unlike other ways of knowing things about the world. But it’s not exactly mystical or inaccessible. On the contrary, it’s positively commonplace. This way of knowing arises when you do something intentionally.
There’s a rich history of philosophical debate about the precise nature of intentional action, but the basics are fairly straightforward. When you do something intentionally, you have in mind something to be done, and you control what happens so as to bring that thing about. For example, intentionally snapping my fingers involves controlling the motion of my middle finger and my thumb so as to produce a quick ‘snap!’ sound when my finger hits my palm. If I control my motions in just that way because I have snapping my fingers in mind as the thing to be done, and I really do end up making that ‘snap!’ sound as a result, then I count as snapping my fingers intentionally. (Note that all-important condition: if the sound doesn’t result, then the whole action doesn’t count as snapping my fingers. It’s called “snapping” for a reason!)
When you do act intentionally, you tend to know what you’re doing—you’re the one doing it, after all! It can’t be a surprise to me that I snap my fingers, given that I’m snapping my fingers intentionally. It also wouldn’t be a surprise to you if you wandered into a closed-door discussion of your promotion—if you were doing that intentionally. The fact that you tend to know what you’re doing, when you’re doing that intentionally, was first discussed extensively by G.E.M. Anscombe (in her 1957 book Intention), and then a little later by Stuart Hampshire (in his 1959 book Thought and Action). This was a philosophically groundbreaking point, but it is also an intuitively plausible one. It might well help explain why you can’t tickle yourself intentionally (you know when it’s coming!), and why you’re less likely to get carsick on a winding mountain road when you’re doing the driving (no twist or turn will be a surprise to your poor stomach).
One remarkable thing about this kind of knowledge, which Anscombe labeled “practical knowledge,” is the way in which you get it. You don’t have to perceive yourself acting, or gather testimony from others, or even do any calculations, in order to know what you’re doing while you’re doing something intentionally. You don’t have to relate to the world in any of these other ways you relate to the world when you gain knowledge.
This is remarkable partly because what you know, when you know what you’re doing, is a fact about the physical world. For example, when I know that I am snapping my fingers, I know that something’s going on that involves a quick, sharp noise, and I know that the hunks of matter that constitute my fingers are making that noise. But I could wear perfect noise-canceling headphones, numb my fingers, and close my eyes while intentionally snapping my fingers, and still know that my fingers are moving in such a way that produces that quick, sharp ‘snap!’ The possibility of cutting off information from my senses, and still having the same knowledge, illustrates the fact that this kind of knowledge doesn’t rely on observation by the senses at all.
More obviously, my knowledge of what I’m doing intentionally doesn’t rely on anyone else’s testimony, or any kind of calculation I could do in my head. It’s not even clear what type of calculation would be relevant to my knowing that I’m snapping my fingers. And it’s only very rarely that anyone else tells you anything about what you’re doing intentionally.
Putting all this together, then, we have a form of knowledge that doesn’t rely on perceptual observation, testimony, or calculation. That’s enough to make it special already. But there’s something else that’s remarkable about practical knowledge, too: this kind of knowledge doesn’t come about after the fact it is knowledge of. Instead, since you know you’re snapping your fingers while doing that intentionally, this knowledge is born as the very fact is made. You come to know you’re snapping your fingers by starting to snap your fingers, and you know that as soon as it’s happening. That means that this way of coming to know doesn’t involve learning, in the sense of gaining knowledge about a pre-existing fact. That’s a second special feature of practical knowledge, on top of its not being based on observation, testimony, or calculation.
These two striking features of practical knowledge can be explained in the same way: when you’re acting intentionally, you’re the one in control here, the one making something happen in the first place. When you’re in control over whether something happens, you don’t need reassurance from your senses, or from other people, in order to know that it happens when you make it happen. You just have the power to make it be so. And the fact of its happening is something you create: you bring it about, you make it happen, and so you are the one to make its happening a fact. It’s the control involved in intentional action that matters to these two special features of practical knowledge.