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Knowledge of things

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As I walk into a restaurant to meet up with a friend, I look around and see all sorts of things in my immediate environment—tables, chairs, people, colors, shapes, etc. As a result, I know of these things. But what is the nature of this knowledge? Nowadays, the standard practice among philosophers is to treat all knowledge, aside maybe from “know-how”, as propositional. But in this paper I will argue that this is a mistake. I’ll argue that some knowledge is constituted, not by beliefs toward propositions, but by awareness of properties and objects. Seeing isn’t believing, but it is knowing. After further characterizing this type of knowledge, I will make the case for it. Then I will consider a variety of objections. Finally, I will indicate how our recognition of this knowledge may answer other questions, and solve other problems, in philosophy.

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  1. 1.

    As Klein (1998) puts it, “One virtually universal presupposition [of contemporary epistemology] is that knowledge is true belief,” where belief is understood as an attitude toward a proposition (pp. 27–33). Whether or not most contemporary philosophers explicitly believe that all knowledge (save know-how) is propositional, this doctrine is consistently reflected in philosophical practice—propositional knowledge is all that’s talked about, for one thing—and it is presupposed in many debates—including debates that other kinds of knowledge would be highly relevant to, such as debates about the structure of knowledge, the nature of justification, the epistemic significance of experience, certainty, intuition, and self-knowledge. So, even setting aside who believes what, the idea that all knowledge (save know-how) is propositional is firmly embedded in contemporary philosophical tradition.

  2. 2.

    One more potential caveat to my claim about what’s standard practice in philosophy (besides the “know-how” caveat) has to do with recent discussions of understanding. Some argue that (i) understanding is a kind of knowledge (see, e.g., Grimm 2006; Salmon 1989). And some argue that (ii) understanding is (at least partly) non-propositional (see, e.g., Zagzebski 2001). If one accepts both (i) and (ii), and also holds that understanding isn’t just a combination of propositional knowledge and know-how, then one will be committed to there being another kind of knowledge that is non-propositional. With that said, few philosophers explicitly endorse either (i) or (ii), and I know of almost no one who explicitly endorses both (i) and (ii) (Grimm (2014) may be an exception; though see Pritchard (2014) for a forceful criticism of precisely this part of Grimm’s account). Indeed, defenders of (i) typically reject (ii), and vice versa, often precisely because they take on board the orthodox assumption that knowledge is constituted by beliefs toward propositions (see, e.g., Grimm, 2006, §7; Zagzebski 2001, pp. 243–244). So, in the end, this caveat doesn’t really threaten my claim that it’s standard practice in philosophy to treat all knowledge (save know-how) as propositional.

  3. 3.

    There are a couple of other philosophers who defend something that is at least similar to knowledge of things. For example, Stump (2010) talks about “Franciscan knowledge”, which is very much like knowledge of things. Fiocco (2017) defends a Brentano-inspired account of something like knowledge of things. Benton (2017) talks about interpersonal knowledge, which is non-propositional and may be a species of knowledge of things. It may be that there are other philosophers out there who just haven’t thought about this issue, or are just focused on other things having to do with propositional knowledge, or for whatever other reason are not opposed to knowledge of things (maybe they even like the idea). If so, then my claims about the philosophical orthodoxy can be understood as being about the way the literature and culture within philosophy have gone over the last few decades.

  4. 4.

    This is the standard view these days. Most philosophers agree that awareness states are not themselves beliefs—they rather cause beliefs about them or about the external world (see Byrne (2016) for an overview). But there are a couple of notable exceptions. Gluer (2009) argues that experiences are beliefs, and Byrne (2016) argues that experiences are partly constituted by beliefs. These accounts are motivated by a desire to capture the epistemic significance of experience. But, as I’ll discuss later, there’s no need to posit beliefs here if I’m right about knowledge of things.

  5. 5.

    Here I am talking about awareness in a way that is most fitting for a representationalist (or intentionalist) view of awareness, which is the most popular view of perceptual experience these days. I will continue to do so. However, the main elements of my account can be reformulated so as to suit other views of perceptual experience, such as naïve realism or the sense-datum theory.

  6. 6.

    Maybe you disagree because you think that the contents of perception are (or include) Russellian propositions that have the objects and properties I see as constituents. If that’s your view, then just note that what I’m talking about as the contents of knowledge of things are the individual objects and properties of which I am aware—what would be the constituent parts of Russellian propositions. So, even if you think that perception is propositional, there’s still room for knowledge of things.

  7. 7.

    Here I take no stand on what the immediate objects of awareness are in, for example, perception. Direct realists think that the immediate objects of perception are objects and properties in one’s environment. But an alternative view is that properties instantiated in our experiences are the immediate objects of awareness.

  8. 8.

    Hence, I take my account of knowledge of truths to be consistent with a “knowledge first” approach to epistemology (see, e.g., Williamson 2000). In fact, even my account of knowledge of things is consistent with the general spirit of that approach (even though as a matter of fact most knowledge-firsters endorse the orthodox view that all knowledge is propositional). For it is consistent with my account that knowledge of things is a fundamental, unanalyzable mental state.

  9. 9.

    There is an ongoing discussion about the extent to which perception itself is conceptual or contains representations of properties like waiter, chair, or oak tree (see, e.g., Siegel 2010; Block 1990). My claims about seeing the waiter as a waiter, as well as the rest of my account of knowledge of things, does not rely on taking any side on this debate. If it turns out that my visual awareness of the waiter as a waiter is partly cognitive, and so isn’t purely perceptual, then that’s fine. That just means that some paradigm cases of knowledge of things aren’t purely perceptual.

    There are all sorts of other controversies about the contents of perception—e.g., about which properties they represent, about their structure, about their relation to phenomenal character, etc.—that I also won’t wade into here.

  10. 10.

    Notice that this is consistent with the idea that we can perceive the cardinality of smaller numbers of objects such that we know via perception how many there are in a given grouping. For example, although I do not know that there are 48 books in front of me just by looking at them (nor do I know of them as 48 books in the sense of knowledge by description), it may be that I know of two pens on my desk as two pens just by looking at them (much like I know of the waiter as a waiter), and it may even be that my visual experience of those two pens automatically generates the belief in me (which may amount to knowledge) that there are two pens there. Still, on my account, these are distinct kinds of knowledge, and it’s at least possible to have knowledge of two pens without knowing that there are two of them (if, for example, one lacked the concept two). My main reason for using an example with a larger number of objects—i.e., 48 books—is to illustrate how knowledge of things not only can but indeed does outstrip knowledge of truths.

  11. 11.

    There are other ways in which knowledge of things is arguably prior to knowledge of truths—for example, it is prior developmentally and phylogenetically. Infants and young children know of objects and properties around them before they know any propositions about them. And (arguably, at least) some non-human animals know of details of their environments, although they (again, arguably) don’t have any propositional knowledge of them (see, e.g., Camp 2009).

  12. 12.

    This point about the obviousness of your knowledge is related to, and reinforced by, another point—namely, that in ordinary language we readily attribute knowledge to people in these kinds of cases. If, when I walked into the restaurant, the hostess said, “Watch out, there’s a waiter in front of you,” I might respond, “Don’t worry, I know.” If you said, “Did you notice the waiter? He looks stressed,” I might say something like, “Yeah, I know, right? I wonder why.” If my mom were there to nag me by saying, “Honey, look out for that chair there, and that one, and that one …,” I’d say, “Yeah, mom, I know, I know, I know.” And if I did happen to bump into a chair, I might explain that I didn’t see it there, and so didn’t know it was there, implying that if only I had seen it, I’d have known it was there and thus would’ve avoided it. So the way we ordinarily speak suggests that we know about the objects and properties of which we are aware.

    You might point out that a lot this talk is being carried out with declarative sentences, which express propositions. But even if I have some propositional knowledge in the above case, which I don’t deny, the point here is that it’s also appropriate, in terms of ordinary language usage, for me to say that I have knowledge about the kinds of objects and properties that I say feature in knowledge of things. As I’ve said, these items of awareness aren’t the kinds of things that we can express, and it’s often difficult, even impossible, to exhaustively describe them. So my linguistic resources are limited in terms of saying exactly what I know in these cases. Nonetheless, the point is, it is appropriate to say “I know” in cases where I intend to refer to specific items of my awareness. And although it’s difficult to describe these things, we can (and do) give each other clues as to what we’re talking about. And often it’s clear we’re saying we know something highly specific. When you mention the waiter’s stress, it’s clear that you are pointing out specific of his properties—his facial expression, for example—that we can see. Or when my mom nags me about the chairs, my response signals that I know about the furniture around me in general, as if to say, “There’s no need to tell me, mom, I know it’s all there!” In each case, it’s clear that what I’m saying I know about is some specific property or object of which I’m aware. Thus, our ordinary language usage supports the claim that we know about these items of awareness.

  13. 13.

    ‘Hallmark’ is a wooly term. I can’t think of a more precise (and yet accurate) single term or description that captures the relation between knowledge and all of the features just mentioned. That’s probably because each feature’s relation to knowledge is different (e.g., justification is necessary for knowledge, evidence is (largely, if not completely) constituted by knowledge, knowledge is used in reasoning, etc.). So what I’ll do is use ‘hallmark’ when grouping these features together—as a way to indicate that they are all distinctive signs or marks of knowledge, and thus evidence of its presence—but then I’ll characterize and discuss the precise relation between each feature and knowledge on a case-by-case basis as I go along.

  14. 14.

    Here I’m ignoring external world skepticism. Indeed, I’ll ignore skepticism throughout this paper. If external world skepticism is true, then knowledge of things may be limited to introspective knowledge. But here I am taking for granted that we know about the external world (and thus of course that this knowledge is justified).

  15. 15.

    Again, I assume that propositions are (at least) abstract bearers of truth and falsity that are expressed (potentially in various ways in various languages) by declarative sentences and marked off by ‘that’-clauses in attitude ascriptions (see Sect. 1).

  16. 16.

    The first three reasons I’ll give are directed just at the orthodox view that all knowledge (save know-how) is constituted by beliefs with propositional contents. They aren’t directed at a different possible view—namely, that my knowledge of the restaurant is constituted by awareness states with (Russellian) propositional contents. I’m not sure anyone holds this view (if they did, they’d have their own burden of defense against the orthodox view), and I suspect that arguments parallel to these first three reasons could be crafted against it. Also, all the other reasons I’ll give in this section count against it.

  17. 17.

    One might suggest that the relevant beliefs aren’t introspectible. But clearly whatever constitutes my knowledge of my ostensible environment is introspectible, since I can (and would, if asked) immediately report that I have this knowledge—that I know about the specific look on the waiter’s face or the layout of furniture in the room (see fn. 12). So if beliefs constitute this knowledge, they should be introspectible.

  18. 18.

    As I mentioned earlier (fn. 10), it may very well be that I would form the relevant belief if the number of objects was smaller (say, 2 or 3). But the point here—which is familiar from discussions of the problem of the speckled hen, among others—is just that, in some cases involving larger numbers of objects (e.g., 48 books), it’s implausible to attribute the relevant beliefs (or, indeed, propositional knowledge) to the subject. I take it that this speaks to a more general, albeit contingent psychological fact about us—namely, that a more-or-less immediate perceptual route to knowledge that there are n number of objects in some location is only available to us when n is a relatively small number.

  19. 19.

    Dretske (1981) nicely illustrates the point that I am making here by giving an analogous cases of representing something with a declarative sentence vs. representing it with a picture:

    If I simply tell you, “The cup has coffee in it,” this … carries the information that the cup has coffee in it in digital form. No more specific information is supplied about the cup (or the coffee) than that there is some coffee in the cup. You are not told how much coffee there is in the cup, how large the cup is, how dark the coffee is … If, on the other hand, I photograph the scene and show you the picture, the information that the cup has coffee in it is conveyed in analog form. The picture tells you that there is some coffee in the cup by telling you, roughly, how much coffee is in the cup, the shape, the size, and the color of the cup, and so on (p. 137).

  20. 20.

    One might say that since in cases of the sort I’ve described I actually see what I’m demonstrating, I naturally have a substantive epistemic grasp of what I’m demonstrating. But then it looks like perception is what’s doing all the epistemic work—like the demonstrative account is merely borrowing a prior substantive grasp afforded by perception. After all, the only difference between substantive perceptual demonstratives and the “blind” demonstratives I mentioned is that I perceive what I’m demonstrating in the former. So the point is, again, that the demonstrative account itself fails to capture the rich, fine-grained nature of my knowledge in the restaurant.

  21. 21.

    These arguments having to do with fineness of grain and demonstratives may seem similar to those offered in favor of the view that some mental content is non-conceptual [see, e.g., Evans (1982), McDowell (1994), Peacocke (1992), and Heck (2000) for discussion]. However, they are in fact distinct (and independent). Conceptualists can embrace knowledge of things, and indeed, they can embrace my argument against the demonstrative account described above—perhaps by saying that, although experience is thoroughly conceptual, there’s just no way we are constantly plugging all those concepts into a vast array of propositions that we then believe. On the other hand, non-conceptualists aren’t automatically committed to knowledge of things. It’s at least consistent with their view to reject it. So the debate over non-conceptual mental content really is distinct from the present arguments. Furthermore, the arguments to follow—particularly those concerning ordinary language and the hallmarks of knowledge—do not rely on the above arguments against the demonstrative account.

  22. 22.

    You might think that some propositions are inexpressible in principle—e.g., semantic paradoxes, or certain mathematical propositions that are beyond our ken. But these propositions, which are different in various ways from the kind of everyday perceptual propositions that are relevant here, are typically (if not always) unknowable. Presumably, in general, if a proposition is knowable—or, indeed, known—then it can be expressed. And I know about the color of your shirt or the taste of scallops (Sect. 2.1). So if this perceptual knowledge is propositional, then it should be expressible. Thanks to Lorraine Keller for bringing this issue to my attention.

  23. 23.

    You might think my view is susceptible to the same awkwardness since, on my view, a lot knowledge of things is inexpressible. But, unlike with propositional knowledge, this is precisely what you’d expect. Objects and properties are, in general, not the kinds of things you can express. Propositions are. So we shouldn’t expect to be able to express knowledge of things, but we should expect to be able to express propositional knowledge.

  24. 24.

    Some philosophers (e.g., Conee 1994; Tye 2009) appeal to these sorts of considerations to defuse Jackson’s (1982) Knowledge Argument against physicalism. They argue that what Mary gains upon leaving her black and white room is knowledge of redness, which can’t be communicated to Mary in her room. They then argue that this accounts for the fact that Mary learns something upon leaving her room, but does so in a way that is consistent with physicalism. For what it’s worth, I like Conee (1994) and Tye’s (2009) assessment of what Mary learns in this case, but I think there remains the important question of whether we should expect that, given physicalism, Mary would be able to gain all physical knowledge third-personally, and indeed, propositionally.

  25. 25.

    In what does this well-foundedness consist? As I suggested in the previous section, it depends on which theory of epistemic normativity you prefer. An externalist might say something like: An awareness state is well founded if and only if it is produced by a reliable cognitive faculty (in the environment for which it was designed), where, in this case, a cognitive faculty is reliable if and only if it produces mostly veridical awareness states (in the environment for which it was designed). An internalist will say something different. She might say: An awareness state is well founded if and only if it is supported by one’s total evidence. Then, as I pointed out earlier, one might develop these accounts in more specific ways—in terms of “epistemic charge” or risk/luck, for example. I won’t pick sides on these debates.

  26. 26.

    Furthermore, consider epistemic normativity having to do with epistemic oughts, and epistemic praise and blame, for example. There is also a parallel with awareness states. I ought to pay attention to certain things—e.g., to the road when I am driving—particularly when I want to know of those things, or when knowledge of those things is relevant to my other epistemic aims or duties. Or if I just want to know about my immediate environment, I ought to look around and see. I can do better or worse as a perceiver, by cultivating (or failing to cultivate) practices that allow me to be in a better (or worse) position to know of the many fine-grained properties around me.

  27. 27.

    So even if an attitude like acceptance is implicated in the well foundedness of my awareness states, it must be automatic—it must come right along with my awareness states—even as a constitutive part of them (cf., Fiocco 2017; Brentano 1874; Kriegel 2018). Byrne (2016) defends a similar proposal, though he argues that beliefs are constitutive of awareness states).

  28. 28.

    Prinz (2002) offers a helpful historical overview of imagism. Proponents include Aristotle, Epicurus, Lucretius, Locke, Berkeley, Hume, Titchener, Russell, and Price. Prinz himself is attracted to a version of imagism.

  29. 29.

    Audi (2010) discusses the philosophical importance of this claim. There are some alleged counterexamples to it [see Warfield (2005) and Luzzi (2014) for discussion]. But even if these are genuine counterexamples (which I doubt), they are far removed from the kinds of cases I’ll discuss below—cases that are clearly good instances of the above claim. Plus, everyone should at least agree that there is a very strong connection between reasoning and knowledge such that if a state features in sound reasoning (in the right way) then we have good reason to think that it’s knowledge.

  30. 30.

    Some say—and you might think—that association is not a genuine form of reasoning, because associations are sometimes brute causal processes that don’t involve deliberation. But this is not always the case. For arguments in favor of treating association as a genuine form of reasoning, see Camp (2014). Camp describes association as “intuitive, holistic, and context-sensitive” (p. 601), and (especially relevant in this context) she points out that, “concrete images play an important role in associative thought” (p. 602). Camp also does a nice job of laying out the benefits and shortcomings of associative reasoning. See also Sloman (1996), Prinz (2002), Carruthers (2006), and Evans (2008).

  31. 31.

    What Camp (2014) says about the quasi-conceptual items that often feature in association, which she calls ‘characterizations’, may sound familiar: “Despite this importantly non-propositional dimension of characterizations, we can still endorse, reject and argue about them. Even though they are complex, nuanced, context-sensitive and intuitive, and even though they may be quite idiosyncratic, they are not just Jamesean causal associations. Endorsing a characterization amounts to accepting that its assignment of fittingness, prominence, and centrality are consistent with the objective distribution of properties in the world (modulo discrepancies introduced by fittingness) and conducive to achieving one’s current cognitive goals. And although I cannot compel you by propositional means to even entertain my characterization, let alone endorse it, I can help you to “get it” by directing your attention toward the features that are most prominent and central for me, and explaining why I take them to be highly intense, diagnostic, central, and fitting” (p. 610–611).

  32. 32.

    See Camp (2014) for an explanation of the differences between deduction (or other forms of propositional reasoning) and association.

  33. 33.

    See Nigel (2017) an overview of these experiments and a general discussion of mental rotation.

  34. 34.

    Thanks to Jack Spencer for causing me to consider whether there are any non-propositional Gettier cases, and to Todd Ganson for bringing examples like the one above to my attention.

  35. 35.

    As I’ve said, there are commonalities between the contents of knowledge of things and knowledge of truths (see Sect. 1). But there are differences between them as well, which I’ve detailed throughout this paper. And I think these differences are interesting and theoretically significant enough to warrant accepting that some knowledge is non-propositional rather than accepting that propositions or beliefs are something other than what we thought.

  36. 36.

    This in itself doesn’t solve every problem in the vicinity. For example, one might still wonder: What is the epistemic significance of perceptual experience for perceptual knowledge of truths? However, my previous discussion about how awareness states figure in our reasoning may go some way to providing an answer here. The answer won’t be that (conscious) awareness states are the only way to generate perceptual knowledge of truths. For once it is established that there’s some perceptual knowledge that requires perceptual experience—namely, some knowledge of things—there is no longer a demand to explain why perceptual experience is sometimes necessary for perceptual knowledge. So the answer regarding perceptual knowledge of truths can be that reasoning with awareness states via association, simulation, mental rotation, and logic, for example, is one way to get new perceptual knowledge of truths.


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Thanks to Tomas Bogardus, Matt Braich, Andrew Cortens, Nina Emery, Trip Glazer, Dan Greco, Louis Gularte, Lorraine Keller, Colin McLear, Paul Nedelisky, Adam Pautz, Doug Reed, Nick Rimell, Tomoji Shogenji, Jack Spencer, Rush Stewart, Donovan Wishon, two anonymous reviewers, and audiences at DePauw University, MIT, Pepperdine University, University of California at Irvine, University of Connecticut, and University of Rhode Island for discussion of and/or comments on this paper.

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Duncan, M. Knowledge of things. Synthese (2018).

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  • Knowledge
  • Knowledge of things
  • Acquaintance
  • Russell
  • Perception
  • Experience