Here I give my preferred explanation of transparency which comes from supplementing the motivational account of belief sketched above, with an account of actual world beliefs. The strategy then is to take a lesson from concerns about teleological and normative accounts—that casting belief as constitutively connected to truth is problematic for explanations of transparency—and thus sever the connection between belief and truth in an account of the nature of belief. Then, I add to this an account of actual world beliefs, i.e., those beliefs of humans. These actual beliefs, in virtue of being beliefs, will meet the motivational condition, but they will also have some additional features in virtue of the particular circumstances in which they are formed. It is these additional features which are key to explaining transparency. We need not, as others have, seek to explain transparency as something stemming from the nature of deliberation over what to believe. The resulting account then will move away both from framing transparency as a product of something believers have a role in producing, and as something which is necessary to deliberation over what to believe.
What follows then is an account of actual beliefs, which I will label as such so as not to confuse it with the motivational account of belief’s nature sketched above. I will also refer to the conjunction of my motivational account of belief and my biological account of actual beliefs as my position. In order to describe my account of actual beliefs, I need to lay some definitional ground. Firstly, I adopt an etiological account of biological function, which I have defended elsewhere (Sullivan-Bissett 2016). The details of the account do not matter here, so to simplify, for a trait to have a proper function it needs to possess one of a set of properties (cashed out in terms of an appropriate range of gene expression), and stand in a causal historical relationship to a token trait which possessed certain properties and was selectively successful.Footnote 18
My account of function is influenced by Ruth Millikan’s and so I will use some of her terms here which do not distinguish between our respective accounts (see Sullivan-Bissett 2016 for discussion of our differences). When we ascribe to a trait a proper function, we ascribe to it a function that was performed by its ancestors, which ‘helped account for the proliferation of the genes responsible for it’ and thus also ‘helped account for its own existence’ (Millikan 1989: p. 289). The heart has the proper function of pumping blood, because it originated as a reproduction of an ancestral heart, which performed the function of pumping blood in the past, and it is this which accounts for the proliferation of the genes responsible for the heart, and therefore the existence of it.
To say of a device that it has a relational proper function is to say of it that ‘its function [is to] produce something that bears a specific relation to something else’ (Millikan 1984: p. 39). Relational proper functions are the effects that have helped account for the selection of the producing mechanism (Millikan 1984: p. 26). To take a toy example; consider the chameleon’s mechanisms for changing the skin pigmentation; they have the relational proper function of producing a skin pattern which matches the chameleon’s environment (Millikan 1984: p. 39). The devices produced by such mechanisms are adapted devices, and that which the adapted device is adapted to is the adaptor (Millikan 1984: p. 40). The produced skin pattern of the chameleon in this instance is the adapted device, with the adaptor being the leaf which the device is produced in relation to.
Finally, I will use the term Normal (note the capitalization) to designate a normative historical (not statistical) sense of normality. For example, sperm Normally fertilize ova, but they do not normally fertilize ova (‘Most never find an ovum and have to call it quits’ (Millikan 1984: p. 34)).
Actual beliefs, truth, and function
With the relevant terms defined, I now offer my functional claim about actual beliefs. Recall that I am building a biological account of actual beliefs onto a motivational account of the nature of belief simpliciter (i.e. belief across worlds).Footnote 19 A belief is a state which plays a certain motivational role, and a biological account of this kind of state as it occurs in the actual world can do the explanatory work called for by transparency. Such an account will ascribe a function to our mechanisms for belief-production, which will provide an explanation of the constraints under which they operate.Footnote 20
The mechanisms which produce beliefs in us have the relational proper function of producing true beliefs.Footnote 21 When mechanisms produce devices in accordance with their relational proper function, they produce devices which are adapted to something else. Our mechanisms for belief-production Normally produce devices which are adapted to the way things are in our environment, that is, they Normally produce beliefs with true contents. Given the biological advantages enjoyed by a creature with mechanisms which produce true beliefs, the mechanisms’ producing such items, causally explains why we have these mechanisms now. Such mechanisms have proliferated because—given the essential nature of belief (its motivational role)—creatures with true beliefs will be more likely to survive because their actions will be successful, given a certain ecology (like the one humans evolved in). The Normal explanation for the performance of this function is that the creature acts on the true belief in such a way as to satisfy its desires.Footnote 22
I note a concern that might be had at this point: if the transition between the deliberative questions is explained by the contingent fact that believing truly is (usually) adaptive, then would it not be that the deliberative question would collapse into the practical question ‘would believing p be adaptive/useful?’ However, the problem with this line of argument is that it suggests that the transition between the questions is agential – that it can be put down to something we do. This is precisely the kind of picture I reject. There is a difference between there being a reason for the transition between the questions (belief’s being a motivational state and our biological history setting us up in such-and-such a way), and the agent having that story as a reason. My claim here is that because believing truly, in circumstances Normal for the production of true beliefs, is adaptive, we are set up such that our deliberative belief formation is transparent to truth. But I am not saying that we, as believers, recognize this as a reason to focus on truth. Our relationship to the structure of deliberative belief formation is much more passive than this—indeed, this is one of the take home messages of the paper.
At this point the reader could be forgiven for thinking that my account of actual beliefs is teleological and thus vulnerable to worries I raised earlier, perhaps it looks like our mechanisms for belief-production are aiming at truth. However, on my account, the only sense in which actual beliefs have an aim is the sense in which they have a biological proper function. My account of actual beliefs captures the agent’s relatively passive response to truth suggestive of biological function, rather than settled by anything at which the agent can be said to be aimed. My account of actual beliefs is teleological but rooted in biology, and does not include an appeal to actual beliefs being aimed at truth in anything but a sub-intentional way. This means that I do not face the dilemma raised earlier, since I explain transparency by appeal to one of the biological functions of the mechanisms which produce actual beliefs, not by appeal to any aim of the agent. There is thus no problem for my account of actual beliefs posed by the exclusivity of truth considerations in deliberation over what to believe, since I do not explain transparency by appeal to an aim, the moderation of one’s activities by which ought to allow for weighing. The aims of action are set by desires and desires can be weighed against each other. So aims in the context of action theory are weighable, or so it seems reasonable to say. Of course there is a sense of aim—that provided by my account of actual beliefs—where aim-talk is just another way of capturing function-talk. But to adopt this line is just to concede that talk of aims is not functioning at the level of action as the teleologist has in mind.
Nor is my motivational account of belief vulnerable to Shah’s teleologist’s dilemma, since my descriptive condition on something’s being a belief does not go via its connection to truth. On my view, an attitude is a belief if it meets some motivational condition, and not if it has some truth-regulatory feature. I do not then face the unhappy task of stipulating the level of truth-regulation required for something to be a belief, such that it captures all those states we want to capture under that label, and it also explains exclusivity to truth in some cases of belief formation.
The biological function of actual beliefs and transparency
I now show how my account of actual beliefs against a background of a motivational account of belief simpliciter, can explain transparency. The explanation I offer appeals to those causal facts about actual belief formation which obtain in virtue of the natural selection of mechanisms which produce beliefs with true contents. As a proponent of an etiological account of biological function, I claim that the fact that a device has a certain function is an explanation for that device’s presence today.
When a subject poses to herself the question whether to believe that p, she attends to the question whether p is true. To demonstrate the structure of my explanation, we can usefully ask two questions about the presence of transparency in doxastic deliberation. First, we can ask a how question: how is there transparency in doxastic deliberation? This question demands an answer providing details of the mechanisms responsible for causing transparency. The explanatory burden here is to give an account of why, when a subject deliberates over whether to believe that p, she moves immediately and inescapably to considering the question whether p is true. The grounds of transparency—of our moving thus—can be given by appeal to certain neurological structures.
In functional terms: transparency is achieved by certain causal facts which hold for our mechanisms for belief-production. Such causal facts make it such that whenever our mechanisms for belief-production Normally perform their relational proper function and produce a true belief, the adaptor in each case is the way the environment is. This is understood at the agent-level as epistemic considerations pertaining to the truth of p. Instances of epistemic considerations settling whether to believe are instances of believers immediately and inescapably attending to the adaptor (the environment) for the adapted device (the belief).
This explanation of how transparency is realized is the same kind of explanation given by the teleological and normative accounts discussed above. All three explanations appeal to something which grounds our moving from the question whether to believe that p to the question whether p is true. On the teleological account, this is explained by appeal to the aim one adopts in posing the deliberative question, on the normative account it is explained by appeal to one’s being guided by the norm governing belief. I argued that these explanations are problematic insofar as the aim and norm are not at the required strength to explain transparency (Sects. 2.1, 3.1). An appeal to biological function does not face this problem, since the move from one question to another is not achieved by anything the agent does, but is rather secured by the biological history of our mechanisms for belief-production. The agent’s role is a passive one, and thus there is no question of answering whether p is true in the positive, and withholding belief because of one’s other aims, or because one recognizes that belief is merely permissible, and not obligatory.
Second, we can ask a why question: why do we move from the question whether to believe that p to the question whether p is true? What explains why the causal facts obtain, which ground our moving between the questions in this way? This question demands an answer which explains why transparency characterizes our deliberation and not something else, realized by a different set of neurological structures. This explanation will tell us why these particular causal facts obtain.
Here we can appeal to natural selection, which selected for the particular neurological structures which ground the move from the question whether to believe that p to the question whether p is true. Given that our mechanisms for belief-production have the relational proper function of producing devices with true contents, the story for their selection includes their Normally producing true beliefs. In the deliberative case our cognitive architecture is arranged such that when we deliberate as to whether to believe that p, we, at the agent-level, are only sensitive to the adaptor (our environment) because this makes the adapted device (the resulting belief) more likely to perform its derived proper function of being true. The neurological structures which secure transparency have been selected for their role in producing true beliefs.
The teleological and normative accounts answer the why question by appeal to the very nature of belief. Why is it that we move from whether to believe that p to whether p is true? Because it is part of the very nature of belief that it is aimed at truth, or governed by a norm of truth. In contrast to these accounts then, my claim is that we have a pre-commitment to truth when we deliberate, this pre-commitment is secured by causal facts which constitute the cause of transparency, and my account of actual beliefs can also explain why these particular causal facts obtain.
My account of actual beliefs leaves it open that there might have been other explanations for why these particular causal facts obtain, and hence that transparency is not essentially to do with biological function. For example, God might make it the case that actual beliefs are transparent to truth considerations. He might ensure that we move from the question whether to believe that p to the question whether p is true, by instantiating certain neurological structures. Leaving this possibility open is all to the good: I embrace the consequence of my account that transparency is not a necessary feature of deliberative belief formation, nor is the way in which it is contingently realized the only way that it might be realized. Other world deliberative beliefs might too be characterized by transparency, without this being explained by biological function. Transparency as exhibited by actual world doxastic deliberation, though, is explainable by appeal to the biological function of the mechanisms which produce beliefs in us.
In the next two sub-sections I will outline and respond to an objection to my explanation of transparency, as well as the supposed virtues of a nearby alternative position which I prefer not to endorse.
Contingency is unacceptable
My explanation appeals to natural selection to explain why the causal structures which realize transparency are present. This means that transparency comes out as a contingent feature of the deliberative beliefs of some believers (i.e., those believers with a biological history), not as a necessary feature of deliberation over what to believe. An objection might be that this consequence of my overall position is unacceptable, and is a reason to reject it. Perhaps it is to be taken as part of the explanandum of transparency that it holds as a matter of metaphysical necessity. This might be taken as something which ideally would be explained, but equally, something which ought not to be abandoned because of failures to explain it.
Here then, I should justify my moderation of the modal strength of transparency. As I argued earlier, other accounts of the nature of belief offer problematic explanations of transparency (at any strength). Such accounts, I suggested, make the mistake of locating the role of truth in belief formation at the intentional level, as something which a subject can aim at, or express her commitment to via being guided by some norm.
Our explanandum is a descriptive fact about belief formation, and I see no reason to think that that descriptive fact is one which is co-instantiated with every instance of deliberative belief across worlds. What needs explaining is why when we deliberate over whether to believe that p, that question collapses into whether p is true, which is why I move from talking about the nature of belief, to talking about the nature of actual beliefs. Why should we think that we ought to build transparency, a feature of actual doxastic deliberation into a claim about the nature of such deliberation simpliciter? Our reason cannot be that belief is constitutively aim-governed, that will not buy transparency, as I have argued (Sect. 2.1). Nor can it be that belief is constitutively norm-governed, since the only plausible formulation of the norm is one which is not strong enough to generate transparency, as I have argued (Sect. 3.1). Teleological and normative accounts then do not necessitate transparency for beliefs formed in the actual world by human believers, let alone for beliefs formed in other possible worlds.
It might be that transparency being taken to have this strong modal status is a function of explanations of it, rather than anything about the phenomenon itself. At least in the case of the teleological account, the explanation of transparency goes via an appeal to the kind of thing belief necessarily is, which is then said to entail the presence of transparency. This has the result that just as the nature of belief goes across worlds, so too does transparency. But given that it is, at the very least, not clear that the teleological account can explain transparency, why keep hold of one of the proposed explanation’s entailments?
Perhaps this is too quick. We might be able to build a case for the strong modal status of transparency independently of the theoretical status of accounts which entail that claim. A natural way of arguing for a necessity thesis about transparency is by appeal to the concept of belief: we might say that it is part of the concept of belief that it is an attitude which exhibits transparency, since it is an attitude which is governed ‘both normatively and descriptively, by the standard of truth’ (Shah and Velleman 2005: p. 499). And so, deliberation over whether to form an attitude that p which does not exhibit transparency is not deliberation over whether to form a belief. One thing to say here is that building the connection to truth into the nature of belief from the start will be friendly to this kind of conceptual claim, but we have already seen that these accounts run into problems when it comes to doing the explanatory work. So I think it is wise to be open to an alternative position, that of understanding the nature of belief as divorced from truth, and then looking to the particular circumstances of belief formation in the actual world. An apparent cost of this alternative is that the necessity thesis is not honoured, and so now we are presented with a choice: pick the accounts of belief which give us problematic explanations of transparency, but honour it as modally strong, where the grounds for understanding it at this strength are given by appeal to a conceptual claim about belief. Or, pick an account of actual beliefs coupled with a motivational account of the nature of belief. This position can explain transparency, but does not honour the strong modal status, and so loses points with the advocates for this conceptual claim. I think that the debate bottoms out at this point.
I also have a principled reason, from my motivational account of belief, to disagree with the conceptual claim Shah and Velleman make which props up transparency as modally strong. Shah and Velleman claim that transparency is distinctive of belief, and it is by appeal to it, that we can distinguish belief from supposition (Shah and Velleman 2005: p. 499). But the motivation for this claim is lost given my motivational account of belief—there is no reason to add to this with respect to providing a demarcating criterion of belief. The motivational role specified earlier captures an important generality across believers, with the link to truth given by features such as transparency as an add-on, which are thus contingent features of belief. To take transparency to be a necessary feature of deliberation over what to believe would just be to project the particular circumstances of our biological heritage into a modal claim.
Given that there are no good reasons to be committed to the necessity claim about Transparency, a position like mine which casts it as contingent should not be objected to on the basis of not honouring the necessity claim. If my position combining belief as a necessarily motivational state with a biological story of actual beliefs is able to do the explanatory work with respect to transparency, then the fact that it does not honour a thesis for which there are no good grounds is surely not a strike against it.
A stronger function account
I might be advised that the problem outlined above can be solved by being more serious about function, that is, by claiming that it is essential to the nature of belief that it is produced by mechanisms with the biological function of producing true beliefs. Such an account would cast my functional claim about actual beliefs as a claim about the kind of thing belief necessarily is (and not merely a claim about the etiology of actual world beliefs). This means that I would not need the motivational role specified earlier as necessary and sufficient for something’s being a belief. Rather, so this view would go, if an attitude is not produced by mechanisms with the biological function of producing true beliefs, whatever that attitude is, it is not a belief. The suggestion then is to take the function claim about actual beliefs to a different level of explanation—to embed that functional claim into one’s account of belief simpliciter. If I were to adopt this account of the nature of belief, there would be no problem arising from casting transparency as contingent. If transparency is to be explained by the biological function of beliefs, and if all beliefs have that biological function as a matter of necessity, transparency will also hold as a matter of necessity.Footnote 23
Though this stronger function account would not be vulnerable to the objection I raised above, we have seen that my position has the resources to diffuse it. So, this stronger function account is not required, and additionally, it raises a particularly difficult problem, which my preferred position does not face. In discussing a component of Velleman’s teleological view, Glüer and Wikforss raise an objection to an account of belief which has as a necessary and sufficient feature of belief the function of the mechanisms which produce it. This view would deny beliefs to an individual without the appropriate history, that is, a history which would bestow upon its mechanisms of belief-production a proper function (Glüer and Wikforss 2013: p. 145). Donald Davidson’s Swampman makes the point: Imagine that I, and a dead tree in a swamp, get struck by lightning. My body is ‘reduced to its elements’, whilst the tree is turned into a molecule for molecule identical version of me (Davidson 1987: p. 443). This replica continues to write philosophy papers, expresses desires to go for 5 km runs, and reports on deliberating about her partner’s (in)fidelity. On the strong function account, my replica is ruled out of having beliefs because of her (lack of) history. Perhaps a proponent of the strong functional account would not balk at this consequence of her view, if she is a historical function theorist then she is accustomed to putative counterexamples which work by removing history and insisting on the presence of some feature nevertheless. So perhaps a strong function theorist would be happy with the consequence that a creature like my Swamp replica could not have beliefs, governed by transparency or otherwise.
However, this is at the very least, it seems to me, a theoretical cost: presumably the strong function theorist would grant the metaphysical possibility of a creature for whom the same causal facts held as do for us. If such a creature were physically and functionally identical to a biological creature, denying that such a creature had beliefs is surely best avoided. My position does not face this problem since I take the functional claim to be a contingent one, insofar as it is a claim about actual world beliefs, not a claim about belief simpliciter.Footnote 24 Providing the state in question has the appropriate motivational role, that state is a belief. My spontaneously coalescing replica can believe that transparency is best explained by appeal to biological function, just as I do.