The paradox of predictability refers to situations in which, even in a deterministic universe, a correct prediction of a future action is seemingly impossible because the agent whose action is predicted is determined to act counterpredictively. In a recent contribution to this journal, Victor Gijsbers provides an example of the paradox in which the undecidability of the situation plays an essential role and claims, additionally, that this undecidability is at the root of all examples of the paradox. This paper argues, (...) first, that the latter claim is not correct because there are clear examples of the paradox in which the situation remains fully decidable. The paper argues, secondly, that, because of its reliance on rather artificial conditions and in contrast with examples referring to the physical nature of the predictor, the example presented by Gijsbers, though technically correct, has little relevance for our understanding of the role of (counter-)predictability in the context of human interactions. (shrink)

Theories of free will are often measured against how well they capture everyday intuitions about free will. But what are these everyday intuitions, and what theoretical commitments do they express? Empirical methods have delivered mixed messages. In response, some free will theorists have developed error theories to undermine the credentials of countervailing intuitions. These efforts are predicated on the idea that people might misunderstand determinism in any of several ways. This paper sheds light on the comprehension problem. We first discuss (...) recent efforts to explain systematic errors in how people interpret determinism. Then, we present the alarming results of two new preregistered studies exploring three types of comprehension failure: (a) epiphenomenal bypassing, (b) fatalistic bypassing, and (c) indeterministic intrusion. Our findings suggest that misunderstanding runs deeper than others have supposed. This casts doubt on existing models of commonsense thinking about free will. Unless and until researchers properly control for the kinds of misunderstandings we identify, research on free will intuitions cannot shed light on whether ordinary thinking reflects commitments to compatibilism or incompatibilism. (shrink)

Scriven’s paradox of predictability arises from the combination of two ideas: first, that everything in a deterministic universe is, in principle, predictable; second, that it is possible to create a system that falsifies any prediction that is made of it. Recently, the paradox has been used by Rummens and Cuypers to argue that there is a fundamental difference between embedded and external predictors; and by Ismael to argue against a governing conception of laws. The present paper defends a new diagnosis (...) of the roots of the paradox. First, it is argued that the unpredictability has to be understood in the light of Turing’s famous results about computability, in particular his proof that there is no solution to the ‘halting problem.’ This allows us to see that previous analyses of the paradox were either mistaken or not fully adequate. Second, the sense of paradox that nevertheless remains is traced to the idea that rational behaviour is not dependent on contingent environmental circumstances: that it is always up to us to engage in activities such as rational prediction or rational belief. The paradox of predictability teaches us that this idea, natural though it may be, is mistaken. (shrink)

In this discussion note we argue, contrary to the thrust of a recent article by Jenann Ismael, that resolving the paradox of predictability does not require denying the possibility of a natural oracle, and thus stands in no need of the response that she proposes.

Determinism is frequently understood as implying the possibility of perfect prediction. This possibility then functions as an assumption in the Manipulation Argument for the incompatibility of free will and determinism. Yet this assumption is mistaken. As a result, arguments that rely on it fail to show that determinism would rule out human free will. We explain why determinism does not imply the possibility of perfect prediction in any world with laws of nature like ours, since it would be impossible for (...) an agent to predict with certainty any future event that is causally influenced by events outside her own backward light cone yet inside the backward light cone of the future event. This is the _light-cone limit_ and it undermines the Manipulation Argument or limits what this argument can tell us about the relevance of determinism to free will. We also respond to objections that the light-cone limit is irrelevant to the Manipulation Argument. (shrink)

If the laws of nature are deterministic, then it seems possible that a Laplacean intelligence that knows the initial conditions and the laws would be able to accurately predict everything that will ever happen. However, it would be easy to construct a counterpredictive device that falsifies any revealed prediction about its future behavior. What would then occur if a Laplacean intelligence encountered a counterpredictive device? This is the paradox of predictability. A number of philosophers have proposed solutions to it, though (...) part of my aim here is to argue that the paradox is more pernicious than has thus far been appreciated, and therefore that extant solutions are inadequate. My broader aim is to argue that the paradox motivates Humeanism about laws of nature. (shrink)