I want to say at the outset that this is not Daniel Dennett's take on knowledge, and in fact he would probably have a lot of scorn for what I say here. I'll get to the reasons for this in a bit, but first I want to talk about the way philosophers traditionally ask questions about knowledge.
Epistemology is one of the major branches of philosophy. It is the study of how we know what we know. It has been studied for about as long as we have had philosophy, which is to say for thousands of years in one form or another. My problem with epistemology, as traditionally done, is that it is infected with the same crypto-Platonism that plagues the philosophy of language.
Traditional epistemologists spin theories of knowledge, apparently guided by common colloquial usage of the word "knowledge" and by their man-in-the-street intuitions of what counts as knowledge and what does not. This would be fine if they openly declared that usage and everyday intuitions were the explanandum, such that what they were really after was a theory that explained usage and intuition, but I've never seen anyone come out and make such a declaration. It would also be fine if they openly declared (and argued for!) the claim that our usage of the word "knowledge" and our intuitions about it were true and faithful reflections of some underlying natural kind, and that using this usage and intuition as falsifiability criteria for their theories was the best way to get at the truth about this natural kind, but they never seem to make this declaration or argument either. I find it frustrating that they do not see the need to even nod in this direction.
My accusation of crypto-Platonism stems from my impression that traditional epistemologists do not, in fact, think that they are studying "mere" usage and fallible intuition, but are zeroing in on some Fact Of The Universe. We are left to infer that epistemologists believe that there is some perfect unchanging definition of knowledge but we just haven't found it yet. So they dive in and "study" this stuff called knowledge, and start coming up with "theories" of it, with various definitions and theories being ruled out because they are susceptible to counter-examples that "clearly" don't constitute true knowledge.
This approach is self-defeating in that to the extent that you elevate your initial intuitions to the status of being the final arbiter of the truth of your theory, you can never reach a counter-intuitive conclusion. The earth revolves around the sun, and not the other way around; time and space behave differently for observers in different frames of reference; whales aren't fish. If you throw away any theories that contradict your initial intuitions, you are pretty much guaranteed not to find any deep but hidden truths.
To get a sense of who I am talking about here, read a little about reliabilism, Gettier problems, or epistemology in general.
Is knowledge, then, a natural kind, like hydrogen, a really-there category of stuff in the universe? Is it the sort of thing about which one might have real predictive theories, theories that might turn out to be right or wrong, perhaps in defiance of our initial intuitions? Or is knowledge more like most of the loosey-goosey cluster concepts we use in everyday life? Or is it the case that in everyday conversation we are sloppy and broad in our use of the term, but when we zero in on a real, rigorous definition, we will find that True Knowledge actually applies to a subset (or superset) of what we have been calling "knowledge" all this time?
Scientists and philosophers refine terms like this, jargonizing everyday words, all the time. They start out investigating something that people call by a certain term, then they find some natural kind at the core of that usage, and they decide to restrict the technical usage of the term to the natural kind (as when we figured out that whales aren't fish). Perhaps they also decide that this term also includes some things that weren't covered by the term before, as in the case of some fish that do not look like fish to the untrained eye.
If investigation reveals a natural category that simply does not line up at all well with any particular commonly used terms, the investigators might decide instead to come up with an entirely new technical term. For example, scientists are content to let people colloquially use the term "light" to mean visible light, while they themselves use "electromagnetic radiation" to refer to the much broader natural kind that actually constitutes light. Alternatively, investigators can continue to use the common term, but stretch its usage to accommodate new facts, using it in a more precise way than most people do in everyday conversation. The decision to tweak the usage of an existing term or come up with a new one is a judgment call, one that is made collectively by the specialists and the entire community of language users as a whole.
The point is that as we investigate, even if we do find some natural kind that lies at the core of our notion of knowledge, we may end up finding that this natural kind, in itself, may or may not line up perfectly with our common usage of the term. In this case we may end up redefining the term "knowledge" in a more technical sense, and this new redefined usage may well exclude some things we might ordinarily call knowledge, and include some things we would not ordinarily call knowledge. On the other hand, if there is a natural kind down in there somewhere but it is just too disjoint with our common usage of the term "knowledge", we may just coin a new term and say that our ordinary notion of knowledge is based on this new thing. Moreover, if there simply is no natural kind that undergirds our everyday notion of "knowledge", we might just stop talking about it altogether in philosophical papers.
The situation with knowledge is a lot like the elements of Aristotelian physics. I'm not saying there is no such thing as knowledge as traditionally conceived, any more than I would say that air, water, earth and fire don't exist. It's just that you can spend centuries calculating the exact ratios of the four "elements" in the various substances you see around you, and you won't have really explained anything in terms of anything more fundamental; you won't have carved Nature at the joints. I suspect that our everyday understanding of "knowledge" is more like Aristotle's earth, and less like hydogen.
So before we spend hundreds of pages arguing about whether or not knowledge is justified true belief, and coming up with counterexamples, we should take a step or three back and figure out what, exactly, the explanandum is. We should try to nail down why we think there is any such thing as knowledge in the first place, what makes us think it might be a natural kind, and what intuitions we have about it that we might be willing to sacrifice for the sake of retaining the name "knowledge" to apply to whatever natural kind we end up identifying at the core of our everyday usage of the term.
What kinds of things do we generally count as knowledge? What makes us think there is any such thing as knowledge, even as a sloppy, colloquial concept, let alone as a perfect unchanging Platonic Idea? This list is not meant to be exhaustive, nor do I mean to imply that these are fundamental categories with crisp boundaries and no overlap, but here are a few different senses in which we use the term "knowledge".
First, there is knowledge by direct acquaintance. When I see red, I know that I am seeing red. When I am in pain, I know that I am in pain. This gets back to that troublesome second orderliness of qualia. Qualia and knowledge of qualia seem pretty inseparable. This observation alone is pretty much all that constitutes Higher Order Thought (HOT) theories.
Closely related to knowledge by direct acquaintance is knowledge by brute association, like the knowledge that fire is hot. Simply reacting to something based on past experience may count as this sort of knowledge. It could be argued that a dog can know that fire is hot, or that it knows it will be smacked with a rolled up newspaper if it steals the meatloaf off the counter. Moreover, I think that you could argue that a dog can know that fire is hot, but that it can't have knowledge by direct acquaintance, e.g. I am hot right now. Making the brute association is a lower bar to clear than possessing the sense of self necessary to know that you are experiencing what you are experiencing. Then again, forming a brute association and acting accordingly might only count as knowledge in a very loose, broad sense. You might be able to think without words, but can you really know without words?
There is also factual, verbally encoded knowledge like Shakespeare quotes or the fact that Moscow is the capital of Russia. Although, as I have argued before, this kind of "dry cognition" is shot through with qualia of its own. Nevertheless, this is the kind of knowledge that rubs up against all kinds of questions about language and the role it plays in our mental lives, since this kind of knowledge seems inherently linguistic. It is digitally encoded, so to speak. Using the power of language, we can know far more complex things than we could ever keep straight using direct acquaintance or brute association alone.
Moving even farther along in terms of abstraction, we have definitional knowledge, which is even more linguistically encoded, and really is about the way we define the terms themselves. The paradigmatic example of this kind of knowledge is that all bachelors are unmarried. That all bachelors are unmarried is a fact, and a fact that I know, but it is not an empirical fact that I found out somehow, but rather it is inherent in how I define my terms in the first place. It is a form of a priori knowledge.
I would also include 2 + 2 = 4 in this category. Of course, this opens up all kinds of possibilities about mathematical truths and the extent to which we are discovering anything "out there" when we do math, as opposed to playing with our own minds. Without going down the philosophy of mathematics rabbit hole too far, I think we can say that I am saying something about how I define 2, 4, +, and = when I assert that 2 + 2 = 4. There is no possible universe in which 2 + 2 does not equal 4. If you say there is, then you are defining your terms quite differently than I do, and it is just a matter of you using a different language, at least with regard to these terms (for instance if you decided that "+" means minus, or that "4" means -9).
We also have inferential, or implied knowledge. If all men are mortal and Socrates is a man, then Socrates is mortal. This is related to definitional knowledge, in that the truth to be known here is implied by the way the terms are defined, but instead of automatically falling out as soon as you know what the words mean, you have to put a little more work in to connect the dots. You can be a perfectly competent language user, with a good command of the terms and their meanings and still not grasp all of the implications of the premises that you know. Indeed, lots of the work people do in mathematics is that of working out obscure implications that are implicit in the premises that are well known to every freshman. Logical inference does not come for free. Knowing the premises is not the same thing as knowing the conclusion.
Once we connect those dots, however, maybe implied knowledge is just a kind of factual knowledge, since once we make an inference, it is knowledge, full stop. Moscow is the capital of Russia, Socrates is mortal. Not quite, though. There is a sense of certainty that clings to knowledge that we derive from other knowledge. Also, depending on context, we sometimes attribute knowledge of this sort to people even when they haven't connected the dots explicitly, but might perfectly well be expected to be able to do so: The power went out, so you know you won't be microwaving a frozen burrito in the immediate future, even if you are just starting to get hungry and had not quite articulated to yourself the desire for a microwaved burrito.
Finally, there is knowledge of missing knowledge. This is not really another category of knowledge itself, but a form of knowledge about our own minds, and how knowledge fits into it. It is really meta-knowledge. Imagine being locked in a room with a numerical keypad lock. You can't get out of the room, and you know that you could if you knew the right combination to type into the keypad. You know that you lack knowledge, and you have a pretty good sense of the scope of the particular knowledge you need, and where it would fit into the store of other knowledge in your head and how you could use it. In the same sense, I know that I don't know more than a few constellations in the night sky. There are many things that I don't know, but I find it odd in these cases that I know pretty much exactly what it would be like to know the keypad sequence, or the constellations, or the types of birds in my back yard. Yes, I am missing the actual knowledge, but the scope of the knowledge I am missing is so narrowly circumscribed that it is defined by its negative space in my mind.
As I said above, these examples of types of knowledge are just meant to mark some of the territory covered by the term. When we do the philosophy of X, we need to review why we think there is any such thing as X in the first place. In this, we can only be guided by our intuitions and common usage (keeping in mind that we declare this up front, and allow intuition and usage to point the way to the phenomenon in question, and do not take them to be any kind of final authority). Do we have any other intuitions about knowledge that might help to constrain the problem? Sometimes, when talking about science, we use the term "know" very broadly, anthropomorphizing: the oceans on Earth know about the moon through its gravitational influence. In this case, to know is to be causally influenced. I think we can safely write this off, at least provisionally, as a case of speaking metaphorically.
What do our intuitions and usage have to tell us about hypothesized knowledge blindsight? What if you had some kind of post-hypnotic suggestion embedded in your mind, so that in certain situations, with certain cues, you would, with 100% reliability, say the appropriate thing, or perform the appropriate action, without "knowing" ahead of time? For instance, if you, as far as you could tell, had no idea of the order of the elements in the periodic table, but if someone asked you what the 31st element was, you found yourself, to your surprise, saying "Gallium". To an outside observer you definitely knew something, even though you did not know that you knew it, and could not summon any sense of the knowledge being there. Would this kind of knowledge, construed in purely functional terms, count as true knowledge? The question is analogous to the question of blindsight with regard to visual qualia, and I suspect has the same answer.
What if your knowledge of the geography of the continents disappeared for 5 minutes while you were driving home from work listening to a song on the radio? Would you notice? We would like to think that we would, that our knowledge is somehow integrated and present even when it is not being actively used at the moment. As with other qualia, however, I think that we might not miss huge swathes of it missing or different, as long as it is not the stuff we are paying attention to right now. Again, there is an analogy with qualia in general here, with similar questions of each.
In all of examples above of types of knowledge, what does it mean to know? I know I am seeing red because I am seeing red. I know that fire is hot, because if I reached my hand out into a fire, it would burn me; if I put a piece of metal in a fire, it would get hot, and it would burn me. If I got on a airplane to Moscow, I would end up in the capital of Russia, and all of the assumptions and expectations I would have on the basis of that expectation would be validated. If I act on my inferred knowledge, my expectations will likewise be validated, and if I only had the combination to the lock, I could get out of this room.
If, if, if. In all but the first case, the word "if" plays a role. When asked to explain or even describe our knowledge, we almost always immediately turn to hypotheticals. In the first case, my direct knowledge of my own conscious state, there is no hypothetical, since the "if" clause is already happening - it is the degenerate trivial case of a hypothetical, in a sense.
I know the cast resin garden Buddha is hard, and I know this with certainty. What does it mean that I know this? I have an immediate, palpable sense that if I were to touch it, if I were to drum my fingernails on it, if I were to rap it with my knuckles, it would feel hard. Some of our expectations regarding these hypotheticals are immediate and sensual, while others are complicated and a little more abstract. I know that I have a certain balance in my checking account because if I wrote a check to buy a new roller coaster for my back yard, the check would bounce, with all the various consequences that would entail.
Is knowledge of something, then, (just) a big bundle of hypothetical expectations? Could it be that we think we have a map, and know things from above, as it were, but really we just have a very elaborate set of directions, situation-specific instructions and chains of if/then clauses that present themselves instantaneously on demand? Does what we think of as descriptive information in our minds end up resolving into a whole lot of prescriptive information with no remainder? And what, in turn, does it mean to have mastered the hypothetical? To know that if . . . then . . ?
If/then clauses have a decidedly algorithmic, prescriptive ring. One associates them with computer programs. To resolve them, you run through the cases. You compute. Could it be, in fact, that we do not actually know in the direct sense that we think we do, for instance, that the Buddha is hard? We only cognitively judge ourselves to know, and have a very good system for coming up with justifications on demand? If this were true, our "knowledge" of something is really just a warm, fuzzy confidence that we know rather than what we normally think of as true, immediate, internalized knowledge. When does complete, just-in-time predictive power and mastery of the hypotheticals become essence?
This is what I think of as Dennettian. What I've just said about knowledge is what he says about qualia. He claims that we don't actually directly experience in the way we think we do, but we (merely) judge ourselves to experience. We actually have a really good mechanism for answering any questions immediately about our field of "experience", and we tell ourselves cognitively that we experience "directly". Could knowledge be that way?
No, and for the same reasons that Dennett is wrong about qualia. I can know that the Buddha is hard, and really sense its hypothetical hardness without actually taking the time to run through any of the imaginary scenarios of touching, drumming, rapping. Again, a smeared-out process becomes a single, unitary thing, grasped all-at-once. In our minds, the prescriptive becomes descriptive. Process becomes thing. The counterfactuals are not just our way of expressing or explaining our knowledge, but are right there, baked into the knowledge itself, and into our sense of having that knowledge. There is a what-it-is-like to know the Buddha statue is hard. I know the Buddha statue is hard with the same sort of certainty that I know that it is hard when I am actually stubbing my toe on it. I am directly acquainted with my knowledge of its hardness. The functional, prescriptive construal of knowledge sounds plausible in the abstract, but fails on subjective, qualitative grounds, just as a purely functional construal of qualia does. There is such a thing as really-there (as opposed to may-be-seen-as) descriptive information, if only in our minds.
In fact, (and if you have been following along you probably saw this coming), I'll take it to its next logical step: knowledge is a quale. Like a lot of qualia, it is a complex all-at-once kind of quale. Interestingly, it is also a Lego-stackable quale, in that it constrains or modifies, or calls into being other qualia. Knowledge applies itself on the fly as the situation calls for it, or seems to present an opening for such application, and incorporates all those implied hypothetical scenarios instantaneously in some way, so that they don't actually have to play out through time in your mind. The ways in which a piece of knowledge can construct or constrain other thoughts you might (or might not) come up with is an inherent part of the knowledge itself. Pieces of knowledge seem to insert themselves and stack and self organize as appropriate; they are, in fact, what I have been calling demons. As such, we must ask the demonic questions: how are they individuated? How do they merge, split apart, fight, reproduce, form alliances, change over time? For what "resources" are they "competing"? What are the rules that govern their Darwinian memescape?
The troublesome second-orderliness of knowledge mirrors that of qualia: seeing red seems inseparable from knowing that you see red, just as knowing that Moscow is the capital of Russia seems inseparable from knowing that you know that Moscow is the capital of Russia. If knowledge-qualia constrains other qualia, and aggressively seeks to apply itself, it makes sense that it would insert itself in any declarations of state by whatever our self-model might be, and we would know that we know, and know that we know that we know, etc. As with inferred knowledge, we don't have to drag the whole derivation of the knowledge into play when we know that we know something; you can know that you know your own phone number without reciting it mentally.
Treating knowledge as a particular kind of qualia, or a way of thinking about qualia, I think, is the most promising approach in terms of zeroing in on knowledge as a natural kind. This echoes my internalism about language and meaning. If you choose to define your terms in such a way as to be an externalist about such things, I can't stop you, and you may be able to come up with an internally consistent system for talking in the terms you define, but you won't have carved Nature at the joints.
The take-home message here is that qualia are not just some magic spray that coats our otherwise functional machinery, or some kind of mood that washes over our minds. Qualia are what our minds are made of, the girders and pistons as well as the paint. The big question, then, is how should we think of this process-as-thing, data-as-algorithm, all-at-once, seen from above, that we see in our own minds but nowhere else in nature? Thinking in terms of computation will only take us so far, and at a certain point, thinking in computational terms will actually mislead us. We need a new model, a new way of thinking about this.