Margot Strohminger is based in Melbourne, where she lectures in philosophy at ACU.
A post by Margot Strohminger
Supposition often comes up in discussions of propositional imagination as a way of getting clearer on what the latter is (not): supposing that p is typically assumed to be different from imagining that p. We can thus expect thinking about the nature of supposition to help theorists of imagination—including readers of this blog—to understand their primary concern. (All this is not to deny that supposition is interesting in its own right. I think it is.)
In this post I will consider one account of what we are doing when we suppose that p. It is part of a recent reductionist theory of imagination defended by Peter Langland-Hassan in his 2020 book, Explaining Imagination. (This blog hosted a discussion of the book when it first appeared—for Peter’s overview, see here).
On the reductionist account, supposition is not a sui generis propositional attitude. Nor is it even a kind of propositional imagination unless, that is, we understand the imagining as one that can be fully explained in terms of some other folk mental states or processes such as beliefs or judgments. In short, Langland-Hassan’s reductionist seeks to explain supposition in terms of a folk psychology which itself has no place for (propositional) imagination.
Having an example on hand can help us to understand and ultimately evaluate this striking proposal. Suppose (!) I ask Peter to do the following and he complies:
(1) Suppose that it rains tomorrow.
What has Peter done? Our reductionist claims that Peter has supposed that it rains tomorrow (and even imagined this to be the case). But they also claim, controversially, the following:
REDUCTION: What it is for Peter to suppose that it rains tomorrow is simply for Peter to A that q, where ‘A’ is a verb phrase in natural language for a folk mental state or process (e.g. ‘believe’, ‘judge’, ‘want’).
REDUCTION is suggested by Langland-Hassan’s view of the imagination more generally (2020: esp. 15). I think REDUCTION faces some challenges, which we can see more clearly once we consider an example of a supposition and its relationship to nearby mental activities.
Let’s consider Peter in a bit more detail. As we’ve assumed already, he supposes that it rains tomorrow. What does the rest of his folk psychology look like? Let’s assume further that he uses the supposition to consider what will happen tomorrow, or more specifically, whether the baseball game will be delayed. Moreover, he ends up judging that the baseball game will be delayed. In this context, there are a few candidates for what our reductionist can identify Peter’s supposition with.
Perhaps most obviously we can identify Peter’s supposition with his judgment about the baseball game: that the game will be delayed if it rains tomorrow. Let’s run with this option. Now consider Amy, who also supposes that it rains tomorrow. Amy might disagree with Peter about the baseball game (thinking it will still go ahead on schedule) or not have any views at all about the game. Intuitively, though, Amy is doing the same thing as Peter. Whatever else Peter’s supposition is, it seems to consist in the same thing as Amy’s supposition. But by hypothesis Amy doesn’t share the game judgment, so his supposition can’t consist in that judgment.
Is there some other folk mental state or process that Peter and Amy must have in common? (Or, put another way, is there some pair of reports of the form, ‘Peter As that q’ and ‘Amy As that q’, that must both be true, given that both comply with (1), as REDUCTION requires?) As far as I can tell, the answer is ‘no’. Suppose we provide a complete characterization of Peter’s and Amy’s minds in the language of folk psychology: each of their beliefs, their desires, their imaginings, their feelings, and so on. The characterizations might differ in every respect apart from the fact that they are supposing that it will rain tomorrow (and, perhaps, imagining it, especially if we treat supposition as a kind of imagination). To take another example, Peter might wonder what will happen if it rains tomorrow. But Amy doesn’t need to in order to comply with (1).
How might our reductionist respond? I can see two options.
First, they might deny my assumption that Amy and Peter’s supposition must consist in the same underlying mental state or process. Or second, they might try to find some other folk mental state or process in common amongst supposers like Peter and Amy. Let’s evaluate these responses in turn.
According to the first possible response, Peter’s and Amy’s suppositions should be explained in different ways. Peter’s supposition that it will rain tomorrow consists in his judgment about the baseball game. But not so for Amy: for Amy it consists in some other judgment (say, the judgment that it will rain only briefly).
Theorists of imagination often maintain that what imagination consists in can vary considerably depending on the context. Amy Kind (2013: 144) notably argues that “there is no ‘single something’” underlying what we do when we imagine across the contexts of fictional engagement, pretense, mindreading and modal epistemology. In this sense the imagination is “heterogenous”.
If we treat supposition as a kind of imagination, or at least relevantly similar to it, then we might expect it too to be heterogenous. However, the heterogeneity needed would have to run much deeper than the one defended by Kind for imagination. In particular, it would follow that there is no single something Amy and Peter are doing when they are both supposing that it will rain tomorrow. Both, we can assume, are using supposition in the same sort of context: they are following my instruction, (1), and it’s not as if one is playing a game but another is mindreading, say. Yet still they are, at some level, taking the attitude of judgment towards different contents.
Worse still it looks as if there are cases where there is no relevant judgment. So we will have to say Peter is taking a different kind of attitude towards a proposition than other subjects who are also supposing it will rain tomorrow. In other words, it doesn’t look as if we can explain all suppositions as judgments about what is being supposed either. One need not arrive at any conclusive beliefs or judgments about tomorrow when one complies with (1). For example, Bence might suppose that it will rain tomorrow and then stop immediately, arriving at no new beliefs by dint of his supposition whatsoever. If that is right, then supposition cannot be explained exclusively in terms of judgment or belief.
The reductionist should be uncomfortable with the deep-seated heterogeneity under consideration. For it would seem to imply that reductive explanations are incredibly cheap and can be found for a whole host of other mental states and processes. Consider an analogous view about desire. Someone who desires to drink a cup of coffee may or may not believe there is one nearby. It is hard to see why we can’t explain her desire as consisting in a belief that there is a cup of coffee nearby in cases where she has the belief though. You may object that others with the desire don’t share her belief but it will cut no ice if we expect heterogeneity: for someone else, we will explain her desire as the belief that there isn’t one nearby (or that there may not be one nearby or…). But our reductionism was not supposed to be this cheap: it was meant to tell us something distinctive about supposition and (other kinds of) imagination.
For this reason I think the second possible response should be considered: perhaps we can find some other folk mental state or process that Peter, Amy (and now Bence) have in common. In closing I will consider two options (and am curious to hear from others if I may be missing a plausible candidate here!).
Consider instructions I might issue instead of (1):
(2) Think about what will happen if it rains tomorrow.
(3) Think about the possibility/eventuality that it will rain tomorrow.
Is it possible to comply with (1) without complying with either (2) or (3)? On this point I am less sure, especially with respect to (3). Recall Bence: perhaps he is at least thinking about the possibility that it will rain tomorrow (even though he doesn’t get very far). Let’s suppose that it isn’t possible. The proposal is now that we can identify S’s supposition that p with S’s thinking about the possibility that p. For this explanation to be adequate by our reductionist’s standards, thinking about possibilities needs to be more “basic” in the following sense (see Langland-Hassan 2020: 15). There need to be cases where we attribute thinking about possibilities to subjects but it is not equally plausible to attribute suppositions to them. So, there will be cases in which Peter thinks about some possibility but he doesn’t suppose anything to be the case. I’m not convinced there are such cases.
Or consider the following instructions:
(4) Ask yourself, Will the baseball game be cancelled if it rains tomorrow?
(5) Ask yourself, What will happen if it rains tomorrow?
Perhaps our making suppositions consists in our asking ourselves certain questions. Langland-Hassan’s (2020) discussion is arguably most suggestive of this option (see ch. 5: n. 7, ch. 6: n. 10, and esp. ch. 8: sect. 8). According to this option, imaginative projects which are initiated by suppositions inevitably involve our asking ourselves certain questions. Thus, for example, when Peter supposes that it rains tomorrow, and he is trying to figure what this will mean for the scheduled game, note how he is asking himself a question. And so, arguably, are Amy and Bence. This option is not challenge-free either. First, it is not clear to me that supposing something to be the case inevitably involves our asking a question. When Bence merely supposes that it will rain tomorrow, does he have to ask himself anything? Second, in cases where supposers are asking themselves questions, there would seem to be considerable variety in the questions they are asking. As we saw, Amy may not ask anything about tomorrow’s game. This will mean that Peter and Amy are taking attitudes towards different propositions even though intuitively their suppositions are attitudes towards the same content. So we are led back to the first problem I raised for the judgment option.
There are a lot of moves our reductionist can make over the course of the challenge I’ve developed. But at the very least considering it will help refine our understanding of supposition and its place in the mind.
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Acknowledgment: Thanks to Peter Langland-Hassan for helpful comments on a draft of this post.
References
Kind, A. 2013. The heterogeneity of imagination. Erkenntnis 78: 141-59.
Langland-Hassan, P. 2020. Explaining Imagination. Oxford: Oxford University Press.