This dissertation is a defense of a particular theory of the metaphysics of time which I call "accretivism", but which is popularly known in a form usually called the "Growing Block Theory". The goal of a metaphysics of time is to incorporate the various aspects of our temporal experience into a single, comprehensive whole. To this end I delineate five aspects of our ordinary experience of time: 1) The Tensed Aspect, in virtue of which objects are presented to us as (...) past, present, or future; 2) The Transitory Aspect, in virtue of which time passes or "flows"; 3) The Durational Aspect, in virtue of which entities have a certain temporal extent; 4) The Structural Aspect, in virtue of which entities are given as being in temporal relations to one another, and 5) The Differential-Repetitive Aspect, in virtue of which things are different from one time to another, and yet there is a certain recurrence of aspects of our experience form one time to another. I contrast the accretivist picture of time, according to which that which is past and that which is present both have ontological status, but nothing which is future has ontological status, and in which temporal passage consists in the coming-into-being of new entities at the temporal edge of reality marked by the present, with the two dominant theories of time in the contemporary literature: 1) presentism, according to which only that which is present has ontological status, and 2) four-dimensionalism, according to which time is to be understood on analogy with spatial dimensions. Accretivism, I argue, is superior to the other two views in virtue of the fact that it gives full status to both the Structural Aspect of Time, for which the presentist has difficulty accounting, and the Transitory Aspect of Time, for which the four-dimensionalist has difficulty accounting. I then defend the accretivist picture against a variety of objections that might be raised to it. (shrink)

Hilbert’s choice operators τ and ε, when added to intuitionistic logic, strengthen it. In the presence of certain extensionality axioms they produce classical logic, while in the presence of weaker decidability conditions for terms they produce various superintuitionistic intermediate logics. In this thesis, I argue that there are important philosophical lessons to be learned from these results. To make the case, I begin with a historical discussion situating the development of Hilbert’s operators in relation to his evolving program in the (...) foundations of mathematics and in relation to philosophical motivations leading to the development of intuitionistic logic. This sets the stage for a brief description of the relevant part of Dummett’s program to recast debates in metaphysics, and in particular disputes about realism and anti-realism, as closely intertwined with issues in philosophical logic, with the acceptance of classical logic for a domain reflecting a commitment to realism for that domain. Then I review extant results about what is provable and what is not when one adds epsilon to intuitionistic logic, largely due to Bell and DeVidi, and I give several new proofs of intermediate logics from intuitionistic logic+ε without identity. With all this in hand, I turn to a discussion of the philosophical significance of choice operators. Among the conclusions I defend are that these results provide a finer-grained basis for Dummett’s contention that commitment to classically valid but intuitionistically invalid principles reflect metaphysical commitments by showing those principles to be derivable from certain existence assumptions; that Dummett’s framework is improved by these results as they show that questions of realism and anti-realism are not an “all or nothing” matter, but that there are plausibly metaphysical stances between the poles of anti-realism and realism, because different sorts of ontological assumptions yield intermediate rather than classical logic; and that these intermediate positions between classical and intuitionistic logic link up in interesting ways with our intuitions about issues of objectivity and reality, and do so usefully by linking to questions around intriguing everyday concepts such as “is smart,” which I suggest involve a number of distinct dimensions which might themselves be objective, but because of their multivalent structure are themselves intermediate between being objective and not. Finally, I discuss the implications of these results for ongoing debates about the status of arbitrary and ideal objects in the foundations of logic, showing among other things that much of the discussion is flawed because it does not recognize the degree to which the claims being made depend on the presumption that one is working with a very strong logic. (shrink)

Since J. McTaggart’s paper on “The Unreality of Time” the opposition of “A-theorists” and “B-theorists” establishes a focal point in the modern debate on the metaphysics of time: While “A-theorists” claim the existence of an objective present, moving along time positions, “B-theorists” maintain that time is just a set of ontologically equivalent coordinates, “now” being merely the indexical of the speaker’s position. Contemporary attempts to resolve the issue by resorting to the analysis of language or to the theory of science (...) seem to deliver no definite results. By contrast, practical and existential aspects of the two models promise to be more univocal guides in deciding between them. Particularly, C. D. Broad’s hybrid conception of a “growing block theory” attains special attractiveness in this regard. (shrink)

Some philosophers contend that the notion of temporal passage is illusory. But if the flow of time is an illusion, what gives rise to the notion that an event is in the future and then becomes present? In this paper, I hypothesize that there is a relation between the degree to which the conditions necessary for an event to occur have been met and the perception that a future event is “distant” or “near” in time. An event is perceived to (...) be “distant” when few or none of the conditions necessary to cause the event have been met. As the conditions necessary to cause the event are attained, the event is perceived to be “near” or “about to happen.” This hypothesis would explain the perception that an event “moves” from the future to the present, but it would not explain why an event that has occurred seems to move from the near past into the distant past. (shrink)

This dissertation offers new proposals, based on a philosophical appraisal of scientific findings, to address old philosophical problems regarding our immediate acquaintance with time. It focuses on two topics: our capacity to determine the length of intervals and our acquaintance with the present moment. A review of the relevant scientific findings concerning these topics grounds the main contributions of this dissertation. Thus, this study introduces to the philosophical literature an empirically adequate way to talk about how the mind represents time (...) at the most fundamental level. In order to account for our immediate acquaintance with the duration of intervals, a theoretical framework for classifying clocks is used to explain why the representational outputs of the circadian clock and the stopwatch have metric structure. A philosophical analysis of these outputs is proposed to classify them and explain their properties. With respect to our immediate acquaintance with the present, a novel two-phase model of the present is proposed. This model shows that there are two forms of acquaintance with the present, which has consequences for contemporary debates in the philosophy of time. (shrink)

In Minkowski spacetime, because of the relativity of simultaneity to the inertial frame chosen, there is no unique world-at-an-instant. Thus the classical view that there is a unique set of events existing now in a three dimensional space cannot be sustained. The two solutions most often advanced are that the four-dimensional structure of events and processes is alone real, and that becoming present is not an objective part of reality; and that present existence is not an absolute notion, but is (...) relative to inertial frame; the world-at-an-instant is a three dimensional, but relative, reality. According to a third view, advanced by Robb, Capek and Stein, what is present at a given spacetime point is, strictly speaking, constituted by that point alone. I argue here against the first of these views that the four-dimensional universe cannot be said to exist now, already, or indeed at any time at all; so that talk of its existence or reality as if that precludes the existence or reality of the present is a non sequitur. The second view assumes that in relativistic physics time lapse is measured by the time co-ordinate function; against this I maintain that it is in fact measured by the proper time, as I argue by reference to the Twin Paradox. The third view, although formally correct, is tarnished by its unrealistic assumption of point-events. This makes it susceptible to paradox, and also sets it at variance with our normal intuitions of the present. I argue that a defensible concept of the present is nonetheless obtainable when account is taken of the non-instantaneity of events, including that of conscious awareness, as that region of spacetime comprised between the forward lightcone of the beginning of a small interval of proper time t and the backward lightcone of the end of that interval. This gives a serviceable notion of what is present to a given event of short duration, as well as saving our intuition of the “reality” or robustness of present events. (shrink)

Keskityn siihen miten Leibnizilla yksittäiset mielihyvän tai mielipahan tiedostamattomat havainnot voivat kasautua tai tiivistyä ja muodostaa vähitellen tunteita, joista tulemme tietoisiksi.

There is a common approach to metaphysical disputes, which takes language as its starting point, and leads to a view about the range of acceptable metaphysical positions in any such dispute. I argue that this approach rests on accepting what I call the Strong Linguistic Thesis (SLT). In the metaphysical debate about time I argue that the new B-theory has rejected SLT, and for good reasons. The metaphysical debate about modality parallels the early metaphysical debate about time. I argue that (...) a position analogous to the new B-theory of time is available in the modal debate, and has some advantages over its rivals. (shrink)