Online research in philosophy

Introduction -- Fatalism, free will, and foreknowledge -- Mind, the metric, and conventionality -- Time travel and backward causation -- Time's origin, and relationism vs. substantivalism -- McTaggart, tensed facts, and time's flow -- Presentism, the block universe, and perduring objects -- The arrow of time -- Zeno's paradoxes and supertasks.

Thinking about time travel is an entertaining way to explore how to understand time and its location in the broad conceptual landscape that includes causation, fate, action, possibility, experience, and reality. It is uncontroversial that time travel towards the future exists, and time travel to the past is generally recognized as permitted by Einstein’s general theory of relativity, though no one knows yet whether nature truly allows it. Coherent time travel stories have added flair to traditional debates over the metaphysical status of the past, the reality of temporal passage, and the existence of free will. Moreover, plausible models of time travel and time machines can be used to investigate the subtle relation between space-time structure and causality.

It surveys some philosophical issues concerning time travel and should serves as a quick introduction. It includes a new and improved way to define a time machine.

This volume presents a selection of the most influential recent discussions of the crucial metaphysical question: What is it for one event to cause another? The subject of causation bears on many topics, such as time, explanation, mental states, the laws of nature, and the philosophy of science. Contributors include J.L Mackie, Michael Scriven, Jaegwon Kim, G.E.M. Anscombe, G.H. von Wright, C.J. Ducasse, Wesley C. Salmon, David Lewis, Paul Horwich, Jonathan Bennett, Ernest Sosa, and Michael Tooley.

The debate about the reality of tense descends from an argument of McTaggart's,whichwas designed to prove the unreality of time.The argument has two constituent theses: firstly that time is intrinsically tensed, and secondly, that the notion of tense is inherently self-contradictory. If both of these theses are true, it follows that time does not exist. The debate that has emerged from this argument centres around the truth or falsity of each of these theses. A-theorists accept the first and reject the second thesis, drawing the conclusion that, since there is no contradiction in the notion of tense, time exists and is intrinsically tensed. B-theorists accept the second and reject the first thesis, concluding that the notion of tense is inherently self-contradictory, but since time is not intrinsically tensed, time exists and is tenseless. I think the argument against tense is sound, but time is not intrinsically tensed, so time exists and is tenseless. However, this argument, which has come to be known as McTaggart's paradox, is obscure, which has tended to blunt its force. In this paper I recast McTaggart's paradox in my own terms. The notion of tense has two components: an observer-independent distinction between past, present and future, and a flow of time. Totake tense seriously is to suppose that these two features of tense are also features of time. I argue that they are inherently incompatible with each other, generating a contradiction at the heart of the notion of tense, thus proving that tense is unreal. The contradiction arises no matter how one construes the notion of tense, and I illustrate this by revealing essentially the same contradiction in a number of different accounts of tensed time.

Tooley here sets out and defends realist accounts of traditional empiricist explanations of causation and laws of nature, arguing that since reductionist accounts of causation are exposed to decisive objections, empiricists must break with that tradition.

This is a study of the nature of time. In it, redeploying an argument first presented by McTaggart, the author argues that although time itself is real, tense is not. He accounts for the appearance of the reality of tense - our sense of the passage of time, and the fact that our experience occurs in the present - by showing how time is indispensable as a condition of action. Time itself is further analysed, and Dr Mellor gives answers to most of the metaphysical questions it provokes, concerning the relation of time to space, the dissection of time, and its relation to change and causation.