According to the Classical Pessimistic Induction (CPI), otherwise positive features like predictive and explanatory success actually cast doubt on theories that display them. After all, they negatively correlate with truth. From this historical track record, it is inferred that current best theories are probably not (even approximately) true. The CPI is often wielded against realists about science, but others like Hume (1757), Pareto (1935), and Hájek (2007) extend it to philosophical theories more generally. In this paper, I unveil a priori (...) refutations that defang the CPI in all its guises. To date, treatments of this topic typically assume the following: if the historical proportion of false theories increases, then it has increasingly negative bearing against realism. I show that this assumption is false. I identify three types of problems for the CPI, each attaching to some interpretation or other. The first problem is that the CPI violates a universal adequacy condition on the confirmation relation that restricts the relationship between entailment and disconfirmation. The second problem is that the induction’s target hypotheses preclude the track record from instantiating a list of epistemically significant properties that empirical information is supposed to afford. The third problem is that it is constitutively impossible for the CPI to have random samples; this implies that even the use of randomization procedures cannot help. In sum: my refutation is novel, accessible by pure reflection, and quite general. (shrink)

In recent years, several philosophers have argued that their discipline makes no progress (or not enough in comparison to the “hard sciences”). A key argument for this pessimistic position appeals to the purported fact that philosophers widely and systematically disagree on most major philosophical issues. In this paper, we take a step back from the debate about progress in philosophy specifically and consider the general question: How (if at all) would disagreement within a discipline undermine that discipline’s progress? We reject (...) two arguments from disagreement to a lack of progress, and spell out two accounts of progress on which progress is compatible with disagreements that persist or increase over time. However, we also argue that disagreement can undermine our ability to tell which developments are progressive (and to what degree). So, while disagreement can indeed be a threat to progress, the precise nature of the threat has not been appreciated. (shrink)

According to some prominent accounts of scientific progress, e.g. Bird’s epistemic account, accepting new theories is progressive only if the theories are justified in the sense required for knowledge. This paper argues that epistemic justification requirements of this sort should be rejected because they misclassify many paradigmatic instances of scientific progress as non-progressive. In particular, scientific progress would be implausibly rare in cases where (a) scientists are aware that most or all previous theories in some domain have turned out to (...) be false, (b) the new theory was a result of subsuming and/or logically strengthening previous theories, or (c) scientists are aware of significant peer disagreement about which theory is correct. (shrink)

What is scientific progress? This paper advances an interpretation of this question, and an account that serves to answer it. Roughly, the question is here understood to concern what type of cognitive change with respect to a topic X constitutes a scientific improvement with respect to X. The answer explored in the paper is that the requisite type of cognitive change occurs when scientific results are made publicly available so as to make it possible for anyone to increase their understanding (...) of X. This account is briefly compared to two rival accounts of scientific progress, based respectively on increasing truthlikeness and accumulating knowledge, and is argued to be preferable to both. (shrink)

The problem of unconceived alternatives can be undermined, regardless of whether the possibility space of alternatives is bounded or unbounded. If it is bounded, pessimists need to justify their assumption that the probability that scientists have not yet eliminated enough false alternatives is higher than the probability that scientists have already eliminated enough false alternatives. If it is unbounded, pessimists need to justify their assumption that the probability that scientists have not yet moved from the possibility space of false alternatives (...) to the possibility space of true alternatives is higher than the probability that scientists have already moved from the former to the latter space. (shrink)

There is much to like about the idea that justification should be understood in terms of normality or normic support (Smith 2016, Goodman and Salow 2018). The view does a nice job explaining why we should think that lottery beliefs differ in justificatory status from mundane perceptual or testimonial beliefs. And it seems to do that in a way that is friendly to a broadly internalist approach to justification. In spite of its attractions, we think that the normic support view (...) faces two serious challenges. The first is that it delivers the wrong result in preface cases. These cases suggest that the view is either too sceptical or too externalist. The second is that the view struggles with certain kinds of Moorean absurdities. It turns out that these problems can easily be avoided. If we think of normality as a condition on *knowledge*, we can characterise justification in terms of its connection to knowledge and thereby avoid the difficulties discussed here. The resulting view does an equally good job explaining why we should think that our perceptual and testimonial beliefs are justified when lottery beliefs cannot be. Thus, it seems that little could be lost and much could be gained by revising the proposal and adopting a view on which it is knowledge, not justification, that depends directly upon normality. (shrink)

A prominent type of scientific realism holds that some important parts of our best current scientific theories are at least approximately true. According to such realists, radically distinct alternatives to these theories or theory-parts are unlikely to be approximately true. Thus one might be tempted to argue, as the prominent anti-realist Kyle Stanford recently did, that realists of this kind have little or no reason to encourage scientists to attempt to identify and develop theoretical alternatives that are radically distinct from (...) currently accepted theories in the relevant respects. In other words, it may seem that realists should recommend that scientists be relatively conservative in their theoretical endeavors. This paper aims to show that this argument is mistaken. While realists should indeed be less optimistic of finding radically distinct alternatives to replace current theories, realists also have greater reasons to value the outcomes of such searches. Interestingly, this holds both for successful and failed attempts to identify and develop such alternatives. (shrink)

Localism is the view that the unit of evaluation in the scientific realism debate is a single scientific discipline, sub-discipline, or claim, whereas individualism is the view that the unit of evaluation is a single scientific theory. Localism is compatible, while individualism is not, with a local pessimistic induction and a local selective induction. Asay (2016) presents several arguments to support localism and undercut globalism, according to which the unit of evaluation is the set of all scientific disciplines. I argue (...) that some of his arguments clash with localism as well as with globalism and support individualism, and that individualism goes hand in hand, while localism does not, with the basic rule of how to evaluate an argument. (shrink)

Individual realism asserts that our best scientific theories are (approximately) true. In contrast, selective realism asserts that only the stable posits of our best scientific theories are true. Hence, individual realism recommends that we accept more of what our best scientific theories say about the world than selective realism does. The more scientists believe what their theories say about the world, the more they are motivated to exercise their imaginations and think up new theories and experiments. Therefore, individual realism better (...) fosters scientific creativity than selective realism. (shrink)

Extensional scientific realism is the view that each believable scientific theory is supported by the unique first-order evidence for it and that if we want to believe that it is true, we should rely on its unique first-order evidence. In contrast, intensional scientific realism is the view that all believable scientific theories have a common feature and that we should rely on it to determine whether a theory is believable or not. Fitzpatrick argues that extensional realism is immune, while intensional (...) realism is not, to the pessimistic induction. I reply that if extensional realism overcomes the pessimistic induction at all, that is because it implicitly relies on the theoretical resource of intensional realism. I also argue that extensional realism, by nature, cannot embed a criterion for distinguishing between believable and unbelievable theories. (shrink)

Scientific realism, the position that successful theories are likely to be approximately true, is threatened by the pessimistic induction according to which the history of science is full of suc- cessful, but false theories. I aim to defend scientific realism against the pessimistic induction. My main thesis is that our current best theories each enjoy a very high degree of predictive success, far higher than was enjoyed by any of the refuted theories. I support this thesis by showing that both (...) the amount, and quality, of scientific evidence has increased enormously in the recent past, resulting in a big boost of success for the best theories. (shrink)

The preface paradox does not show that it can be rational to have inconsistent beliefs, because preface writers do not have inconsistent beliefs. I argue, first, that a fully satisfactory solution to the preface paradox would have it that the preface writer's beliefs are consistent. The case here is on basic intuitive grounds, not the consequence of a theory of rationality or of belief. Second, I point out that there is an independently motivated theory of belief – sensitivism – which (...) allows such a solution. I sketch a sensitivist account of the preface writer's doxastic state. (shrink)

In 1962, the publication of Thomas Kuhn’s Structure ‘revolutionized’ the way one conducts philosophical and historical studies of science. Through the introduction of both memorable and controversial notions, such as paradigms, scientific revolutions, and incommensurability, Kuhn argued against the traditionally accepted notion of scientific change as a progression towards the truth about nature, and instead substituted the idea that science is a puzzle solving activity, operating under paradigms, which become discarded after it fails to respond accordingly to anomalous challenges and (...) a rival paradigm. Kuhn’s Structure has sold over 1.4 million copies and the Times Literary Supplement named it one of the “Hundred Most Influential Books since the Second World War.” Now, fifty years after this groundbreaking work was published, this volume offers a timely reappraisal of the legacy of Kuhn’s book and an investigation into what Structure offers philosophical, historical, and sociological studies of science in the future. (shrink)

Reply to Goldman I would like to thank Alvin for a spirited, and gentlemanly, debate we’ve had on these issues, which is extended further here. Alvin is exactly right that if we make his assumption about maximum specificity and deduceability (which I have doubts about), then on my view of knowledge Sphere Guy doesn’t know there’s a sphere in front of him. This may sound silly when we focus on his tactile access to the sphere in the actual world, but (...) if we take a broader view we see that there is more at stake than this. Contrary to Alvin’s impression, methods are not at all excised from my view of knowledge. My theory of how to judge whether someone knows requires us to consider everything (probable) that is and would be responsible for the fact that the person believes or not, whether these occur in his head or in the world, which the formulation in terms of probability helps to make very clear. (See Chapter 3.) Ironically, my refusal to relativize to method has us taking into consideration more facts about the subject’s method than Alvin’s criteria do, for my view takes into account, as appropriate, what process the person would have used and has a tendency to use, and not just the properties of the one he happened in fact to use. When the fact that a method was used by a subject in coming to belief in p is independent of the truth of p, which is actually most of the time in our lives, the conditions of application of the variation condition insure that we evaluate the subject by considering only what he would do and how he would fare in his beliefs were he to use that method he actually used. So, under that condition, my view agrees with Alvin, and Nozick also. But when whether a subject used that method is not independent of the truth value of p, then the variation condition in my view says we must consider in addition the subject’s resulting beliefs in all probable scenarios where he is such that he might well.. (shrink)

"Partial realism" is a common position in the contemporary philosophy of science literature. It states that the "essential" elements of empirically successful scientific theories accurately represent corresponding features the world. This thesis makes several novel contributions related to this position. Firstly, it offers a new definition of the concept of “empirical success”, representing a principled merger between the use-novelty and unification accounts. Secondly, it provides a comparative critical analysis of various accounts of which elements are "essential" to the success of (...) a theory, including structural realism and the divide et impera strategy. A novel account of essentialness, entitled the “empirically successful sub-theory "account", is defended. Thirdly, it is argued that the realism/anti-realism debate should put to the side metaphysical questions and focus instead on partial realism's commitment to the continuity of science. Because this commitment lacks metaphysical implications, it is referred to as "deflationary realism". Anti-realists cannot reject deflationary realism as a matter of a priori principle; its overall viability can therefore only be assessed by a careful examination of the history of science. Finally, another consequence of partial realism, named "partial rationalism", is defended. Partial rationalism states that, in cases where several competing theories have been suggested, scientists are rational just in case they accept the essential elements of each of the scientific theories on offer. This novel position subverts the existing literature on scientific "revolutions", as it sometimes demands that scientists devise a synthesis between competing scientific theories, instead of "choosing" only one. The philosophical points defended in this thesis are illustrated and supported by case studies from the history of science, including Fresnel’s wave theory of light, the Copernican revolution, the "neo-Darwinian synthesis" in evolutionary biology, the "prion revolution" in molecular biology, the miasma theory of disease, and the chemical revolution. (shrink)

The paper seeks to answer two new questions about truth and scientific change: What lessons does the phenomenon of scientific change teach us about the nature of truth? What light do recent developments in the theory of truth, incorporating these lessons, throw on problems arising from the prevalence of scientific change, specifically, the problem of pessimistic meta-induction?

Recently, Fahrbach and Park have argued that the pessimistic meta-induction about scientific theories is unsound. They claim that this very argument does not properly take into account scientific progress, particularly during the twentieth century. They also propose amended arguments in favour of scientific realism, which are supposed to properly reflect the history of science. I try to show that what I call the argument from scientific progress cannot explain satisfactorily why the current theories should have reached a degree of success (...) that excludes their future refutations and allows the inference to their truth. I further argue that this line of argumentation dismisses the burden of proof in a rather unfair manner by using a delaying tactic to postpone the question about the validity of the PMI in the future. (shrink)

I argue that scientific realism, insofar as it is only committed to those scientific posits of which we have causal knowledge, is immune to Kyle Stanford’s argument from unconceived alternatives. This causal strategy is shown not to repeat the shortcomings of previous realist responses to Stanford’s argument. Furthermore, I show that the notion of causal knowledge underlying it can be made sufficiently precise by means of conceptual tools recently introduced into the debate on scientific realism. Finally, I apply this strategy (...) to the case of Jean Perrin’s experimental work on the atomic hypothesis, disputing Stanford’s claim that the problem of unconceived alternatives invalidates a realist interpretation of this historical episode. 1 Stanford’s Argument from Unconceived Alternatives2 Previous Attempts to Undermine the Problem of Unconceived Alternatives2.1 The plausibility of unconceived alternatives2.2 The distinctness of unconceived alternatives2.3 The induction from past to present3 Causal Knowledge as a Criterion for the Realist3.1 How Chakravartty’s proposal differs from earlier causal strategies3.2 Causal realism and the detection/auxiliary distinction4 Causal Realism, Unconceived Alternatives, and the Atomic Hypothesis4.1 Perrin and the philosophers: some initial observations4.2 Roush and Stanford on Perrin4.3 From Brownian motion to the reality of atoms4.4 What we know about atoms5 Conclusion. (shrink)

The pessimistic induction plays an important role in the contemporary realism/anti-realism debate in philosophy of science. But there is some disagreement about the structure and aim of the argument. And a number of scholars have noted that there is more than one type of PI in the philosophical literature. I review four different versions of the PI. I aim to show that PIs have been appealed to by philosophers of science for a variety of reasons. Even some realists have appealed (...) to a PI. My goal is to advance our understanding of what the various PIs can teach us about science and the threat posed by PIs to scientific realism. (shrink)

ABSTRACTMany discussions of the ‘preface paradox’ assume that it is more troubling for deductive closure constraints on rational belief if outright belief is reducible to credence. I show that this is an error: we can generate the problem without assuming such reducibility. All that we need are some very weak normative assumptions about rational relationships between belief and credence. The only view that escapes my way of formulating the problem for the deductive closure constraint is in fact itself a reductive (...) view: namely, the view that outright belief is credence 1. However, I argue that this view is unsustainable. Moreover, my version of the problem turns on no particular theory of evidence or evidential probability, and so cannot be avoided by adopting some revisionary such theory. In sum, deductive closure is in more serious, and more general, trouble than some have thought. (shrink)