Science, realism, and unconceived alternatives: introduction to the special issue on unconceived alternatives

Unconceived alternatives and the cathedral problem Abstract Kyle Stanford claims we have historical evidence that there likely are plausible unconceived alternatives in fundamental domains of science, and thus evidence that our best theories in these domains are probably false. Accordingly, we should adopt a form of instrumentalism. Elsewhere, I have argued that in fact we do not have historical evidence for the existence of plausible unconceived alternatives in particular domains of science, and that the main challenge to scientific realism is rather to provide evidence that there are likely not plausible unconceived alternatives. In the present paper, I contend that we may come to have such evidence in the long run of science. I then investigate the epistemic consequences of the claim that we presently do not have evidence for or against the existence of plausible unconceived alternatives, but that in the future we may come to have evidence against the existence of plausible unconceived alternatives. I argue there are prima facie reasons to endorse a form of voluntarism in this situation according to which scientists and others may rationally be more optimistic or more pessimistic about the truth of our best theories, on the grounds that the widespread acceptance of an obligation to be an instrumentalist threatens to disrupt the proper functioning of science, in part because the domain of application of the problem of unconceived alternatives is unclear.

Inductive explanation and Garber–Style solutions to the problem of old evidence Abstract The Problem of Old Evidence is a perennial issue for Bayesian confirmation theory. Garber (Test Sci Theor 10:99–131, 1983) famously argues that the problem can be solved by conditionalizing on the proposition that a hypothesis deductively implies the existence of the old evidence. In recent work, Hartmann and Fitelson (Philos Sci 82(4):712–717, 2015) and Sprenger (Philos Sci 82(3):383–401, 2015) aim for similar, but more general, solutions to the Problem of Old Evidence. These solutions are more general because they allow the explanatory relationship between a new hypothesis and old evidence to be inductive, rather than deductive. In this paper, I argue that these solutions are either unsound or under-motivated, depending on the case of inductive explanation that we have in mind. This lends support to the broader claim that Garber–Style Bayesian confirmation cannot capture the sense in which new hypotheses that do not deductively imply old evidence nevertheless seem to be confirmed via old evidence.

Dilemmic Epistemology Abstract This article argues that there can be epistemic dilemmas: situations in which one faces conflicting epistemic requirements with the result that whatever one does, one is doomed to do wrong from the epistemic point of view. Accepting this view, I argue, may enable us to solve several epistemological puzzles.

Historical inductions, Old and New Abstract I review prominent historical arguments against scientific realism to indicate how they display a systematic overshooting in the conclusions drawn from the historical evidence. The root of the overshooting can be located in some critical, undue presuppositions regarding realism. I will highlight these presuppositions in connection with both Laudan’s ‘Old induction’ and Stanford’s New induction, and then delineate a minimal realist view that does without the problematic presuppositions.

Accommodation, prediction and replication: model selection in scale construction Abstract In psychology, measurement instruments are constructed from scales, which are obtained on the grounds of exploratory and confirmatory factor analysis. Looking at the literature, one can find various recommendations regarding how these techniques should be used during the scale construction process. Some authors suggest to use exploratory factor analysis on the entire data set while others advice to perform an internal cross-validation by randomly splitting the data set in two and then either perform exploratory factor analysis on both parts or exploratory factor analysis on the first part and confirmatory factor analysis on the other. In spite of all these divergent recommendations, there is no consensus on which method yields the best result. In this paper, we analyze this issue in light of the prediction versus accommodation debate and argue that the answer to this question depends on one’s conception of the criteria that should be used to achieve the goals of the scientific enterprise.

Towards a theory of singular thought about abstract mathematical objects Abstract This essay uses a mental files theory of singular thought—a theory saying that singular thought about and reference to a particular object requires possession of a mental store of information taken to be about that object—to explain how we could have such thoughts about abstract mathematical objects. After showing why we should want an explanation of this I argue that none of three main contemporary mental files theories of singular thought—acquaintance theory, semantic instrumentalism, and semantic cognitivism—can give it. I argue for two claims intended to advance our understanding of singular thought about mathematical abstracta. First, that the conditions for possession of a file for an abstract mathematical object are the same as the conditions for possessing a file for an object perceived in the past—namely, that the agent retains information about the object. Thus insofar as we are able to have memory-based files for objects perceived in the past, we ought to be able to have files for abstract mathematical objects too. Second, at least one recently articulated condition on a file’s being a device for singular thought—that it be capable of surviving a certain kind of change in the information it contains—can be satisfied by files for abstract mathematical objects.

A pragmatic argument against equal weighting Abstract We present a minimal pragmatic restriction on the interpretation of the weights in the “Equal Weight View” (and, more generally, in the “Linear Pooling” view) regarding peer disagreement and show that the view cannot respect it. Based on this result we argue against the view. The restriction is the following one: if an agent, \(\hbox {i}\) , assigns an equal or higher weight to another agent, \(\hbox {j}\) , (i.e. if \(\hbox {i}\) takes \(\hbox {j}\) to be as epistemically competent as him or epistemically superior to him), he must be willing—in exchange for a positive and certain payment—to accept an offer to let a completely rational and sympathetic \(\hbox {j}\) choose for him whether to accept a bet with positive expected utility. If \(\hbox {i}\) assigns a lower weight to \(\hbox {j}\) than to himself, he must not be willing to pay any positive price for letting \(\hbox {j}\) choose for him. Respecting the constraint entails, we show, that the impact of disagreement on one’s degree of belief is not independent of what the disagreement is discovered to be (i.e. not independent of j’s degree of belief).

Extending the argument from unconceived alternatives: observations, models, predictions, explanations, methods, instruments, experiments, and values Abstract Stanford’s argument against scientific realism focuses on theories, just as many earlier arguments from inconceivability have. However, there are possible arguments against scientific realism involving unconceived (or inconceivable) entities of different types: observations, models, predictions, explanations, methods, instruments, experiments, and values. This paper charts such arguments. In combination, they present the strongest challenge yet to scientific realism.

Smelling objects Abstract Objects are central to perception and our interactions with the world. We perceive the world as parsed into discrete entities that instantiate particular properties, and these items capture our attention and shape how we interact with the environment. Recently there has been some debate about whether the sense of smell allows us to perceive odours as discrete objects, with some suggesting that olfaction is aspatial and doesn’t allow for object-individuation. This paper offers two empirically tractable criteria for assessing whether particular objects are exhibited in perceptual experience—(1) susceptibility to figure-ground segregation and (2) perceptual constancies—and argues that these criteria are fulfilled by olfactory perception, and thus there are olfactory objects. I argue that there are, in fact, two different ways that olfaction allows for figure-ground segregation. First, I look at various Gestalt grouping principles, which are thought to govern when features are perceived as grouped into structured wholes, segregated from everything around them. I argue that these principles apply to olfactory experience, providing evidence of non-spatial figure-ground segregation. Second, I defend the contentious idea that a spatial variety of figure-ground segregation can also occur in olfaction. To see this, however, we need to look to empirical evidence showing that tactile stimulation and bodily movements play a crucial role in olfactory phenomenology. Finally, I draw on empirical evidence and olfactory phenomenology to argue that there are perceptual constancies in olfactory experience, allowing us to perceive odours as coherent objects that survive shifts in our perspectives on the world.