I'm back from travel to Paris and Antwerp, where I spoke with people influenced by, and critical of, my "dispositionalist" approach to belief. A critique of my work has also just appeared in the journal Theoria. It's an honor to be criticized!
Over the years, I've advanced various arguments for dispositionalism about belief (here, here, here, here, here, here, here). Today, I want to synthesize and restate the most fundamental one.
Dispositionalism Characterized
According to dispositionalism as I understand it, to believe some proposition P is nothing more or less than to have a certain suite of behavioral, cognitive, and phenomenal (that is, conscious experience involving) dispositions. Which dispositions? Dispositions of the sort that we are apt to associate with belief that P. This might sound circular, but it's not: It is to ground metaphysics in commonsense psychology. Stealing an example from Gilbert Ryle, to believe that the ice is dangerously thin is to be prone to skate warily, to dwell in the imagination on possible disasters, to warn other skaters, to agree with other people's assertions to that effect, to feel alarm and surprise upon seeing someone skate successfully across it, and so on, including being ready generally to make plans and draw consequences that depend on the truth of P.
[Midjourney rendition of skaters approaching thin ice]
As is typical of dispositions in general, the relevant dispositions hold only ceteris paribus (all else being equal or normal or right). For example, you might not be disposed to warn other skaters if you'd like to see them fall in. The dispositions are potentially limitless in number: Less obvious ones include the disposition to assume that a circular disk cut from the ice would be fragile and the disposition to attend curiously to a fox walking across the ice. One needn't possess every disposition on the infinitely expandable list in order to count as a P believer -- just enough of the dispositional structure that attributing the belief to you adequately captures your general cognitive posture toward P.
Although dispositionalism about belief can seem confusing, dispositionalism about personality traits is intuitive. Thus, comparison to personality traits is instructive. Consider extraversion. To be an extravert is nothing more or less than to have the dispositional profile stereotypical of extraversion: a tendency to say yes to party invitations, a tendency to enjoy meeting new people, a readiness to take the lead in conversation and in organizing social events, and so forth. Of course all of these dispositions are ceteris paribus and no one is going to to be 100% extraverted down the line. Match the dispositional characterization of extraversion closely enough, and you're an extravert; that's all there is to it. Similarly, match the dispositional characterization of being a thin-ice believer closely enough, and you are one; that's all there is to it.
The Fundamental Argument
Now consider some alternative, non-dispositionalist account of belief, where believing is constituted by some feature other than one's overall dispositional profile with respect to P. Call that alternative feature Feature X. Maybe Feature X is having a stored representation with the content that P. Maybe Feature X is having a particular neural structure. Maybe Feature X involves being responsive to evidence for or against P. If Feature X is metaphysically distinct from having a belief-that-P-ish dispositional structure, then it ought to be possible in principle to imagine cases in which Feature X is absent and the dispositional structure is present and vice versa. I submit that in such cases, first, we intuitively do, and second, we pragmatically ought, to attribute belief in a way that tracks the belief-that-P-ish dispositional structure rather than the presence or absence of Feature X. That's the fundamental argument.
As a warm-up, consider space aliens. Tomorrow, they arrive from Alpha Centauri. They learn our languages, trade with us, fall in love with some of us, join our corporations and governments, write philosophy and psychology articles, reveal their technological secrets, and recount amazing tales about their home planet. Stipulate, too, that we somehow know their cognitive dispositions and their phenomenology (that is, their streams of conscious experience). We know that if they say "P is so, I'm sure of it!" and then not-P is revealed to be true, they normally feel surprise. We know that they have inner speech and imagery like ours, and that when they assert that P they tend to draw further logical conclusions from P and make plans that will only work if P is true.
I submit that if we know all these dispositional facts about the aliens, we know that they have beliefs. What kinds of brains do they have? What kind of underlying cognitive architecture? How did they come to have their present dispositional structures? Who knows! As far as belief is concerned, it doesn't matter. They have what it takes to believe.
Suppose that Feature X is having internal structured representations of a certain sort. Imagine, now, a space alien -- call her Breana -- with a radically different cognitive architecture from ours, lacking internal structured representations of the required sort, but possessing the behavioral, cognitive, and phenomenal dispositions characteristic of belief. Breana will act and react, behaviorally, emotionally, and cognitively, just like an entity with beliefs. Maybe Breana says "microbes live beneath the ice of Europa" with a feeling of sincerity and accompanying visual imagery of slime beneath the ice. She draws relevant conclusions (Earth is not the only planet with life in the Solar System). She would feel confused and surprised if a seemingly knowledgeable friend contradicted her. If a human asked where we should probe to find alien life, she would recommend Europa. And so on. Breana believes, despite lacking internal structured representations of the required sort.
My opponent might say that if Breana acts and reacts as I have described her, then she must have internal representations of the required sort and thus would not be a counterinstance to a representationalist account. I respond with a dilemma: Either representationalism does not commit to the existence of internal representations of the required sort whenever the belief-that-P-ish dispositional structure is present or it does commit. If the former, then we ought to be able to construct a Breana-like case without the required underlying representations, producing the objectionable case of the previous paragraph. If the latter -- that is, if it is metaphysically or conceptually necessary that whenever a belief-that-P-ish dispositional structure is present, the entity has the required representational structure -- then the so-called "representationalism" collapses into dispositionalism: The dispositions drive the metaphysical car, so to speak, and having the pattern of dispositions is just what it is to represent.
How about the converse case, where the representational structure is present but the dispositions are absent? Breana has a stored representation with the content P, but she has no inclination to act or react, or to reason or plan, accordingly. "Microbes live beneath the ice in Europa" is somehow internally represented, but she would not assent to that proposition verbally or in inner speech; she would feel no surprise upon learning that it is false; she would never make any plans contingent upon its truth; when she imagines Europa, she pictures it as sterile; if quizzed on the topic, she would fail; in no condition could she be provoked to remember that she learned this; and so on. Breana will of course sincerely deny that she believes P. It would be strange to insist that despite her sincere protests, she really does believe.
Thus, to the extent that representationalism's Feature X comes apart from dispositional structure, our intuitive standards of belief attribution follow the dispositional structure rather than the presence or absence of Feature X. And that's how it should be. What we can and do care about in belief attribution is the believer's overall cognitive posture toward the world -- how they are disposed to act and react, what they will affirm and depend on, what they take for granted in their inferences, and so forth -- not whether there's a tokening of "P" in a hidden mental warehouse.
Note that unlike old-school behaviorist dispositionalism, this argument is immune to concerns about puppets and play-acting. (Actually, I think the behaviorist has some underappreciated resources here, but dispositionalism of the form I prefer need not rely on those resources.) Puppets aren't conscious and don't reason, so they have no phenomenal or cognitive dispositions. Actors who pretend to believe that P while really holding not-P have the phenomenal and cognitive dispositions characteristic of not-P, including relying on not-P in their own deceptive plans, and the ceteris paribus clause is triggered for their behavioral dispositions, explaining why they don't act like P believers. (Compare: An extravert paid a large sum to act like an introvert is really still an extravert.)
Other approaches to belief are vulnerable to the same fundamental argument. Suppose that Feature X involves the capacity to rationally revise your belief in the face of counterevidence. Now imagine someone who acts and reacts exactly like a P-believer, matching the dispositional profile in every respect, except that they stubbornly eschew any counterevidence. We ordinarily would, and should, describe that person as a P-believer. They will self-ascribe the belief, insist on its truth, reason from it, plan on its basis, and so forth. Of course they believe it! In fact, if they would never revise it, we might be inclined to say they believe it very strongly indeed.
Suppose that Feature X involves something about the causal history of the belief state: To be a belief, the cognitive state must have been caused in a certain way. Now imagine Swampman: Lightning strikes a swamp, and by freak quantum chance a molecule-for-molecule duplicate of your favorite philosopher emerges. Let's stipulate (though it's complicated) that this philosopher has all the dispositions characteristic of belief. We would, and should, say that Swampman believes. Or imagine a conscious robot, printed fresh from the factory with a full set of behavioral, cognitive, and phenomenal dispositions. This robot believes, even though the disposition, for example, to say "Earth is approximately spherical" did not arise in the usual way from evidence or testimony to that effect. Again, this seems both natural to say and to track what we do and should care about in ascribing beliefs.
Suppose that Feature X involves a normative standard. A belief is a state that is "correct" only if it is true. Either assessibility by this standard corresponds with having the required dispositional structure, or assessibility by this standard can come apart from having the required dispositional structure. If the former, then being assessible by the normative standard is a consequence of having the dispositional structure constitutive of believing. If the latter, then either there are beliefs that are not normatively assessible in that way (e.g., religious beliefs?) or there are states that are normatively assessible in the way we normally assess beliefs but which are not in fact beliefs (e.g., delusions?).
The Metaphilosophical Frame
Although I think alternative views often face empirical problems (especially concerning "in-between" cases of belief in which people only approximately match the relevant dispositional profiles), the fundamental argument as I've described it here doesn't rely on empirical objections to alternative views. Instead, it relies on a particular metaphilosophical approach.
Stipulate that we can define "belief" in a dispositionalist way or alternatively in some other way, and that both definitions are coherent and face no insuperable empirical obstacles. Now we, as philosophers, face a choice. How do we want to define belief? What definition captures what we do care about and should care about in belief ascription? What way of thinking about belief sorts cases in the way it's most useful to sort them?
We will ordinarily, I think, find it natural and intuitive to sort cases by the dispositionalist criteria. That creates a default supposition in favor of dispositionalism. But dispositionalism might not always track ordinary patterns of belief ascription. In some cases, our intuitions are ambivalent or go the other way. (See my discussion of intellectualism, for example.) More important, the dispositionalist approach tracks what matters in belief ascription. Dispositionalism captures what we should most want to capture with the term "belief" -- that is, our general dispositional posture toward the truth of P, whether we will affirm it, defend it, rely on it in planning and inference, feel confident when we contemplate it, and so forth.
I’m very sympathetic but I have a quibble. Or maybe two. Let’s agree that the skater who believes the ice is thin is disposed to skate warily and etc. Doesn’t she have that disposition (in this case) because she believes what she does? Her reason for being disposed to skate warily is that, as she sees it, the ice is thin. So I’m worried your account can’t get the link between what a person believes and how they are disposed to act quite right. That’s my first quibble. The second one concerns what manifests or reveals her belief when she does skate warily. I’m not sure her wary skating manifests her belief. She might skate warily for all kinds of reasons. Maybe she is hoping to win a bet that requires that she skate warily. What manifests her belief, when she skates warily, is the fact that she is skating warily because, as she sees it, the ice is thin. It is her acting for that reason that manifests her belief. I worry your account gets the manifestation of belief wrong. These are quibbles. But I’d be curious to hear how you think belief links up with having a reason for being disposed and for acting.