The philosophy of time travel is a sub-field of metaphysics – the study of what there is and what things are like – that considers questions about the possibility of time travel and what a world in which time travel is possible looks like. These questions range from whether time travel is actually possible, to how time travellers can act in the past or future. This thesis delves into a particularly interesting, yet historically undertreated theme: the abilities of time travellers (...) and relatedly their freedom as well. The abilities and freedom of time travellers has been the source of a lot of recent discussion with some polarising views. The minority (which includes Lewis (1976), but also Ted Sider (2002)) argue for the affirmative – that time travellers are free and have the same (or perhaps more) abilities as non-time travellers. The majority (which includes Kadri Vihvelin (1996), Michael Rea (2005), Stephanie Rennick (2015), Alison Fernandes (2020), amongst others) argue for the negative, that time travellers do not have exactly the same freedoms and abilities as non-time travellers. I think that it is a mistake to be so pessimistic about the abilities and freedom of time travellers. I treat concerns about the freedom of time travellers and concerns about the abilities of time travellers as two sides of the same coin. Therefore, in what follows, I argue for two related conclusions. First, I argue that time travellers have all sorts of abilities. Second, I argue that time travellers are just as free as non-time travellers. In arguing for these conclusions, I first produce a novel analysis of ability which reveals important details about how abilities track inputs rather than outputs. Second, I use this new analysis of ability to present a new compatibilist account of free will. If I am right in arguing positively for the abilities and freedoms of time travellers, then this has large implications for both the current time travel discourse and the general debate surrounding freedom. Significantly, I am arguing against some prominent views about time travel and in suggesting that these views are mistaken, I am presenting new ideas about ability and freedom: specifically, that time travellers have the ability and are free to do impossible things. (shrink)

The consequence argument is among the most influential arguments for the conclusion that free will and determinism are incompatible. Recently, however, it has become increasingly clear that the argument fails to establish that particular incompatibilist conclusion. Even so, a version of the argument can be formulated that supports a different incompatibilist conclusion, according to which free will is incompatible with our behavior being predetermined by factors beyond our control. This conclusion, though not equivalent to the traditional incompatibilist thesis that determinism (...) strictly precludes free will, is something many incompatibilists have had in mind all along and, indeed, is arguably the more central incompatibilist position. The consequence argument thus remains philosophically important, even if, as several of its critics have argued, it can't be used to establish the strict incompatibility of free will and determinism. (shrink)

The consequence argument purports to show that determinism is true only if no one has free will. Judgments about whether the argument is sound depend on how one understands locutions of the form 'p and no one can render p false'. The main interpretation on offer appeals to counterfactual sufficiency: s can render p false just in case there is something s can do such that, were s to do it, p would be false; otherwise, s cannot render p false. (...) Here I show that, in the context of the consequence argument, this interpretation conflicts with widely endorsed principles governing the logic of counterfactuals. (shrink)

Do incompatibilist arguments, like some fatalist arguments, rest on modal fallacies? If Westphal (2012) is right, then one popular argument for incompatibilism van Inwagen’s “First Formal Argument” does rest on a modal fallacy. Similarly, Warfield (2000) claims that the standard modal formulation of the master argument for incompatibilism is a modal fallacy. Here, I refute both claims. Contra Westphal, I show that the mistake in van Inwagen’s "First Formal Argument" is no modal fallacy. After that, I argue that Warfield’s charge (...) of modal fallacy can be easily avoided by using a plausible principle concerning actuality. Then, I show that this allows one to put forward a fairly simple argument for fatalism (the thesis that we aren’t able to do otherwise from what we actually do). (shrink)

Let (leeway) incompatibilism be the thesis that causal determinism is incompatible with the freedom to do otherwise. Several prominent authors have claimed that incompatibilism alone can capture, or at least best captures, the intuitive appeal behind Jorge Luis Borges's famous “Garden of Forking Paths” metaphor. The thought, briefly, is this: the “single path” leading up to one's present decision represents the past; the forking paths that one must decide between represent those possible futures consistent with the past and the laws (...) of nature. But if determinism is true, there is only one possible future consistent with the past and the laws and, hence, only one path to choose from. That is, if determinism is true, then we are not free to do otherwise. In this paper, I argue that this understanding of the Garden of Forking Paths faces a number of problems and ought to be rejected even by incompatibilists. I then present an alternative understanding that not only avoids these problems but still supports incompatibilism. Finally, I consider how various versions of (leeway) compatibilism fit with the Garden of Forking Paths as well as the broader question of whether metaphors, however intuitive, have any dialectical force in the debates over freedom. (shrink)

Determinism is a claim about the laws of nature: very roughly, it is the claim that everything that happens is determined by antecedent conditions together with the natural laws. Incompatibilism is a philosophical thesis about the relevance of determinism to free will: that the truth of determinism rules out the existence of free will. The incompatibilist believes that if determinism turned out to be true, it would also be true that we don't have, and have never had, free will. The (...) compatibilist denies that determinism has the consequences the incompatibilist thinks it has. According to the compatibilist, the truth of determinism does not preclude the existence of free will. (Even if we learned tomorrow that determinism is true, it might still be true that we have free will.) The philosophical problem of free will and determinism is the problem of understanding, how, if at all, the truth of determinism might be compatible with the truth of our belief that we have free will. That is, it's the problem of deciding who is right: the compatibilist or the incompatibilist. (shrink)

This thesis investigates the conceptual relationship between laws of nature and free will. In order to clarify the discussion, I begin by distinguishing several questions with respect to the nature of a law: i) do the laws of nature cover everything that happens? ii) are they deterministic? iii) can there be exceptions to universal and deterministic laws? iv) do the laws of nature govern everything in the world? In order to answer these questions I look at three widely endorsed accounts (...) of laws: "Humean" regularity accounts, laws as relations among universals, and the dispositional essentialist account. I argue that there is nothing in the very nature of a law - in any of the accounts surveyed - that implies a positive answer to questions (i) and (ii). I show that this has important consequences for the free will problem. I then turn to the compatibility of free will and determinism. I focus on the Humean view and the dispositional essentialist account of laws. And the bulk of this discussion concerns the consequence argument, especially the question of whether the laws of nature are "up to us". I show that, on the dispositional conception of laws, there is no sense in which the laws of nature are up to us, contrary to the Humean view. However, this does not mean that there is no room for free will on the dispositional account. I argue that free will requires the laws of nature to be limited in scope, rather than being indeterministic. I conclude by showing that this allows one to resist the claim that indeterminism rules out free will. (shrink)