Diversity Reading List

Abstract: Do time travellers retain their normal freedom and abilities when they travel back in time? Lewis, Horwich and Sider argue that they do. Time-travelling Tim can kill his young grandfather, his younger self, or whomever else he pleases—and so, it seems can reasonably deliberate about whether to do these things. He might not succeed. But he is still just as free as a non-time traveller. I-ll disagree. The freedom of time travellers is limited by a rational constraint. Tim can-t reasonably deliberate on killing his grandfather, certain that he-ll fail. If Tim follows his evidence, and appropriately self-predicts, he will be certain he won-t kill his grandfather. So if Tim is both evidentially and deliberatively rational, he can-t deliberate on killing his grandfather. This result has consequences. Firstly, it shows how evidential limits in the actual world contribute to our conception of the future as open. Secondly, it undercuts arguments against the possibility of time travel. Thirdly, it affects how we evaluate counterfactuals in time travel worlds, as well as our own. I-ll use the constraint to motivate an evidential and temporally neutral method of evaluating counterfactuals that holds fixed what a relevant deliberating agent has evidence of, independently of her decision. Using this method, an agent-s local abilities may be affected by what happens globally at other times, including the future.

Abstract: In this paper I give consideration to some apparent impossibilities for the time travelers to the past. After criticizing the views of D. Lewis and K. Vihvelin, I will show in what sense they are really impossible.

Abstract: Here are some intuitions we have about the nature of space and time. There is something fundamentally different about the past, present, and future. What is definitive of the past is that the past events are fixed. What is definitive of the future is that future events are not fixed. What is definitive of the present is that it marks the objective ontological border between the past and the future and, by doing so, instantiates a particularly salient phenomenological property of nowness. Call the combination of these intuitions according to which there exists an objective present, a fixed past, and an open future, the intuitive view. I argue that, given the intuitive view, the possibility of backwards causation - and hence, for instance, backwards time travel - is problematic.

Abstract: It has been suggested that there is something worrisome, puzzling, or incomprehensible about the sorts of causal loops sometimes involved in backwards time travel. This paper disentangles two distinct puzzles and evaluates whether they provide us reason to find backwards time travel incomprehensible, inexplicable, or otherwise worrisome. The paper argues that they provide no such reason.

Abstract: In this paper, I argue that the thesis that time travel is logically possible, is inconsistent with the necessary truth of any of the usual 'open future objective present' models of the universe. It has been relatively uncontroversial until recently to hold that presentism is inconsistent with the possibility of time travel. I argue that recent arguments to the contrary do not show that presentism is consistent with time travel. Moreover, the necessary truth of other open future-objective present models which we might, prima facie, have supposed to be more amenable to the possibility of time travel, turn out also to be inconsistent with this possibility.

Abstract: David Lewis famously argued that the time traveller ‘can’ murder her grandfather, even though she never will: it is compossible with a particular set of facts including her motive, opportunity and skill (1976: 150). I argue that while ordinary agents ‘can’ under Lewis’s conception, philosophers cannot – the latter will not only fail to fulfill their homicidal intentions but also fail to form them in the first place.