Online research in philosophy

We offer a formal account of the English past tenses. We see the perfect as having reference time at speech time and the preterite as having reference time at event time. We formalize four constraints on reference time, which we bundle together under the term ‘perspective’. Once these constraints are satisfied at the different reference times of the perfect and preterite, the contrasting functions of these tenses are explained. Thus we can account formally for the ‘definiteness effect’ and the ‘lifetime effect’ of the perfect, for the fact that the perfect seems to ‘explain’ something about the present, and that the perfect cannot presuppose a past time point. We explain why perfect and preterite can sometimes be interchangeable, and we offer a solution to the ’present perfect puzzle’. We explain the unacceptability of notorious examples of the perfect such as * Gutenberg has discovered the art of printing . We give greater definition to the familiar notions of ‘current relevance’ and ‘extended now’.

This article discusses the argument we cannot have knowledge of abstract entities because they are not part of the causal order. The claim of this article is that the argument fails because of equivocation. Assume that the “causal order” is concerned with contingent facts involving time and space. Even if the existence of abstract entities is not contingent and does not involve time or space it does not follow that no truths about abstract entities are contingent or involve time or space. I argue that it is the latter which is required to obtain the desired conclusion.

No one denies that time and space are different; and it is easy to catalog differences between them. I can point my finger toward the west, but I can’t point my finger toward the future. If I choose, I can now move to the left, but I cannot now choose to move toward the past. And (as D. C. Williams points out) for many of us, our attitudes toward time differ from our attitudes toward space. We want to maximize our temporal extent and minimize our spatial extent: we want to live as long as possible but we want to be thin.1 But these differences are not very deep, and don’t get at the essence of the difference between time and space. That’s what I want to understand: I want to know what makes time different from space. I want to know which difference is the fundamental difference between them.

Unsurpassed among books on space and time in terms of its insights and clarity, this volume by a world-famous mathematician can be appreciated by lay readers as ...

We have, however, as the title of the book would suggest, dealt mainly with space and time, introducing mechanical and electromagnetic considerations only when ...

Time, Space, and Metaphysics engages with major philosophical questions concerning time and space, a framework for the investigation being provided by the ...

Space and time are the most fundamental features of our experience of the world, and yet they are also the most perplexing. Does time really flow, or is that simply an illusion? Did time have a beginning? What does it mean to say that time has a direction? Does space have boundaries, or is it infinite? Is change really possible? Could space and time exist in the absence of any objects or events? What, in the end, are space and time? Do they really exist, or are they simply the constructions of our minds? Robin Le Poidevin provides a clear, witty, and stimulating introduction to these deep questions and many other mind-boggling puzzles and paradoxes. He gives a vivid sense of the difficulties raised by our ordinary ideas about space and time, but he also gives us the basis to think about these problems independently, avoiding large amounts of jargon and technicality. His book is an invitation to think philosophically rather than a sustained argument for particular conclusions, but Le Poidevin does advance and defend a number of controversial views. He argues, for example, that time does not actually flow, that it is possible for space and time to be both finite and yet be without boundaries, and that causation is the key to an understanding of one of the deepest mysteries of time: its direction. Drawing on a variety of vivid examples from science, history, and literature, Travels in Four Dimensions brings to life some of the most profound questions imaginable.

Isaac Newton founded classical mechanics on the view that space is something distinct from body and that time is something that passes uniformly without regard to whatever happens in the world. For this reason he spoke of absolute space and absolute time, so as to distinguish these entities from the various ways by which we measure them (which he called relative spaces and relative times). From antiquity into the eighteenth century, contrary views which denied that space and time are real entities maintained that the world is necessarily a material plenum. Concerning space, they held that the idea of empty space is a conceptual impossibility. Space is nothing but an abstraction we use to compare different arrangements of the bodies constituting the plenum. Concerning time, they insisted, there can be no lapse of time without change occurring somewhere. Time is merely a measure of the cycles of change within the world.

Extending on an earlier paper [Found. Phys. Ltt., 16(4) 343–355, (2003)], it is argued that instants of time and the instantaneous (including instantaneous relative position) do not actually exist. This conclusion, one which is also argued to represent the correct solution to Zeno’s motion paradoxes, has several implications for modern physics and for our philosophical view of time, including that time and space cannot be quantized; that contrary to common interpretation, motion and change are compatible with the “block” universe and relativity; and that time, space, and space-time too, cannot exist. Instead, motion and change become the major players.

Modern cosmology treats space and time, or rather space-time, as concrete particulars. The General Theory of Relativity combines the distribution of matter and energy with the curvature of space-time. Here space-time appears as a concrete entity which affects matter and energy and is affected by the things in it. I question the idea that space-time is a concrete existing entity which both substantivalism and reductive relationism maintain. Instead I propose an alternative view, which may be called non-reductive relationism, by arguing that space and time are abstract entities based on extension and changes.