Aspects of Time

I will show how a metaphysical problem of Arthur Prior’s can be solved by a logical tool he developed himself, but did not put to any foundational use: metric logic. The broader context is given by the key question about the metaphysics of time: Is time tenseless, i.e., is time just a structure of instants; or is time tensed, because some facts are irreducibly tensed? I take sides with Prior and the tensed theory. Like him, I therefore I have to (...) deal with a more specific metaphysical question: How can the instants of tenseless time be reduced to tensed facts? This is the point where, on the technical level, hybrid logic and metric logic come in. For present purposes, both can be seen as species of tense logic; and both are creations of Prior. In his argument for the tensed theory of time, Prior used hybrid tense logic to reduce instants. But, as he himself pointed out, this reduction runs into deep problems, because it immediately generalizes to other categories, for example and most importantly to persons. My main aim is to show that metric logic does not run into similar difficulties: It will help the tensed theory reduce instants, but it leaves persons untouched. I will also give reasons for preferring a metric to a hybrid logic of time that are independent of the metaphysical issue of reduction, but concern temporal reasoning, natural language semantics, and the epistemic side of time-keeping. (shrink)

This paper aims to clarify the connection between the logic of temporal distinctions and the temporal features of propositions. Contra Prior, it argues that the adoption of tense operators does not commit one to the view that propositions can change their truth value over time.

Arthur N. Prior, in the Preface of Past, Present and Future, made clear his indebtedness to “the very lively tense-logicians of California for many discussions”. Strangely,with a notable exception of Copeland, there is no extensive discussion of these scholars in the literature on the history of tense logic. In this paper, I propose to study how Nino B. Cocchiarella, as one of the Californian tense-logicians, interacted with Prior in the late 1960s. By gathering clues from their correspondence available at Virtual (...) Lab for Prior Studies, I will highlight some of the differences between their views on tense-logic, which might still have far-reaching philosophical implications. I will conclude with a sketchof how to study in what ways Prior and Cocchiarella influenced some other Californian tense-logicians. (shrink)

A-theorists think there is a fundamental difference between the present and other times. This concern shows up in what kinds of properties they take to be instantiated, what objects they think exist and how they formalize their views. Nearly every contemporary A-theorist assumes that her metaphysics requires a tense logic – a logic with operators like and. In this paper, I show that there is at least one viable A-theory that does not require a logic with tense operators. And I (...) will argue that three common indispensability arguments for tense operators are unsound. (shrink)

A review of Huw Price's Time's Arrow and Archimedes' Point.

The author reflects on the moral attitudes displayed by Poles fighting in the Warsaw Uprising. He believes that the sacrifice and selflessness with which Varsovians battled for their city had its roots in the general mentality of the Poles, who for generations had been raised in the spirit of “mutual and willing endowment”. He also notes that the noble ideals of the wartime generations have today been largely replaced by mercenary selfishness.

These nine essays address fundamental questions about time in philosophy, physics, linguistics, and psychology. Are there facts about the future? Could we affect the past? In physics, general relativity and quantum theory give contradictory treatments of time. So in the current search for a theory of quantum gravity, which should give way: general relativity or quantum theory? In linguistics and psychology, how does our language represent time, and how do our minds keep track of it?

If Jones buttered the toast at midnight, there is, according to Davidson, an event of Jones’ buttering of the toast. But what kind of temporal phenomenon is being referred to if Jones is in the midst of buttering the toast? By taking a Davidsonian events-based semantics as its starting point, this thesis seeks an answer to the question of “What account of temporal ontology is needed in order to explain the semantic features of the progressive aspect in English?”. In order (...) to answer the foregoing question, this thesis critically evaluates several contemporary accounts of the ontology of process, or, equivalently, the temporal ontology associated with the English progressive. These ontological accounts of process—namely those advocated by several notable neo-Davidsonians, as well as accounts by authors such as Taylor, Steward, Crowther, and Hornsby—will all be found to be wanting. By developing some remarks entered by Dummett concerning a famous passage by Frege on the notion of countability, this thesis ends by suggesting how it is that the comparatively austere temporal ontology associated with traditional Davidsonian semantics provides us with a plausible temporal ontology of the English progressive. (shrink)

In this paper I am concerned with analyzing in detail how ideas and expectations regarding the role of time in quantum theory arose and evolved in the early years of quantum mechanics. The general theme is that expectations which seemed reasonable from the point of view of matrix mechanics and Dirac's q-number formalism became implausible in light of Dirac-Jordan transformation theory, and were dashed by von Neumann's Hilbert space formalism which came to replace it. Nonetheless, I will identify two concerns (...) that remain relevant today, and which blunt the force of Hilgevoord's claim that the demand that time feature as an observable arose as the result of a simple conceptual error. (shrink)

David Albert claims that classical electromagnetic theory is not time reversal invariant. He acknowledges that all physics books say that it is, but claims they are ``simply wrong" because they rely on an incorrect account of how the time reversal operator acts on magnetic fields. On that account, electric fields are left intact by the operator, but magnetic fields are inverted. Albert sees no reason for the asymmetric treatment, and insists that neither field should be inverted. I argue, to the (...) contrary, that the inversion of magnetic fields makes good sense and is, in fact, forced by elementary geometric considerations. I also suggest a way of thinking about the time reversal invariance of classical electromagnetic theory -- one that makes use of the invariant formulation of the theory -- that makes no reference to magnetic fields at all. It is my hope that it will be of interest in its own right, Albert aside. It has the advantage that it allows for arbitrary curvature in the background spacetime structure, and is therefore suitable for the framework of general relativity. (shrink)

This paper investigates what the source of time-asymmetry is in thermodynamics, and comments on the question whether a time-symmetric formulation of the Second Law is possible.

Life is short. This indisputable fact of existence has driven human ingenuity since antiquity, whether through efforts to lengthen our lives with medicine or shorten the amount of time we spend on work using technology. Alongside this struggle to manage the pressure of life’s ultimate deadline, human perception of the passage and effects of time has also changed. In _On Borrowed Time_, Harald Weinrich examines an extraordinary range of materials—from Hippocrates to _Run Lola Run_—to put forth a new conception of (...) time and its limits that, unlike older models, is firmly grounded in human experience. Weinrich’s analysis of the roots of the word _time_ connects it to the temples of the skull, demonstrating that humans first experienced time in the beating of their pulses. Tracing this corporeal perception of time across literary, religious, and philosophical works, Weinrich concludes that time functions as a kind of sixth sense—the crucial sense that enables the other five. Written with Weinrich’s customary narrative elegance, _On Borrowed Time_ is an absorbing—and, fittingly, succinct—meditation on life’s inexorable brevity. (shrink)

Why does time seem to flow in one direction? Can we influence the past? Is only the present real? Does relativity conflict with our common understanding of time? How does time relate to free will? Could science do away with time? These questions and others about time are among the most puzzling problems in philosophy and science. In this exciting collection of original articles, eminent philosophers propose novel answers to these and other questions. Based on the latest research in philosophy (...) and physics, these essays will be enjoyable to anyone with a speculative turn of mind. (shrink)

Augustine’s analysis of time in Book XI of Confessions represents for Ludwig Wittgenstein a good example of a philosophical question. In dealing with such theme, his thought undergoes relevant changes. In the Philosophical Remarks, written more than 10 years after the drafting of the Tractatus, the Austrian philosopher holds that the essence of the world can be expressed in the grammar of language. Philosophy as “custodian” of grammar can grasp the essence of the world by excluding nonsensical combinations of signs. (...) Philosopher, however, are often “tempted” to straightly describe the nature of the world, producing logical-grammatical paradoxes. An example of such a temptation is offered by the attempt to take hold of the essence of time using propositions like “only the present experience has reality.” The logical mistake hidden in this proposition lies in the bad use of the adjectival word “present” that would lose its everyday use and functional role in the language. Only comparing the term “present” with the background of other words referring to time experiences like “past,” “future,” and so on, we are able to understand the true sense of it. Engaging in a grammatical investigation into the notion of time helps us to dispel the different uses of it staving off logical muddles. Wittgenstein makes, in his lecture held at Cambridge in 1932–1933, a relevant distinction between what he calls “memory-time” and “information-time.” If the first can be understood as a now-centered system mostly expressed by indexical sentences or as an arrangement relied on memory, and therefore inadequate to give any external physical criteria for time measurements, the second clearly refers to a public chronology, implemented by clocks, calendars, diaries, and so on. Grammatical misconceptions, however occur when we are “tyrannized” by a metaphor and not able to “move outside of” it. The Austrian philosopher makes no secret of preferring a characterization of time that rejects a truth-functional interpretation. As for the notion of “game” in the Philosophical Investigations, it is impossible to have something like a common denominator shared by every sentence involving time. (shrink)

In her Transient Truths, Berit Brogaard defends temporalism about proposition content from the more traditional eternalist views. I argue that both temporalism and eternalism are equally capable of accommodating all the data, and thus suggest that we should adopt a neutralism that holds there is no serious or resolvable dispute. Contra Brogaard, I argue that neither disagreement patterns nor belief dynamics favor temporalism over eternalism. I also suggest that Brogaard's defense of operator over quantificational semantics for tense is unnecessary, because (...) quantificational tense semantics can be given a temporalist reading, and operator tense semantics can be given an eternalist reading. (shrink)