The Origins of Temporal Experience
Sydney :: 16-17 July 2004
From A to B, or back again? Subjective and objective
in the temporal realm
Defenders of the B-series hold that there is no objective 'now', no passage or flow of time, and no temporal 'becoming'. They often argue that modern physics supports this view. Advocates of the A-series either dispute this claim about modern physics, or argue that if it is true, then modern physics leaves out something fundamental (namely, the central temporal aspect of reality).
These debates are crucial to one of the deepest issues in philosophy and science, the distinction between 'subjective' and 'objective' aspects of our naive view of reality. The temporal aspects of this issue are unresolved in important ways, but central to our undertstanding of physics, metaphysics and our own place in the world.
This conference presented new work on these themes under three main headings:
Becoming Accessible to Physical Theories?
The literature on the compatibility between the time of our experience characterized by passage or becoming and time as is represented within spacetime theories has been affected by a persistent failure to get a clear sense of the notion of becoming, in its relation both to an ontology of events spread in a four-dimensional manifold, and to temporally asymmetric physical processes. My paper tries to remedy this situation (1) by explicating the unclear notion of becoming and (2) by discussing its possible relevance to physical theories.
I begin by arguing that the metaphysical debate between the so-called presentists (A-theorists) and eternalists (B-theorists) is completely irrelevant to the question of becoming, as such a debate is generated by a failure to distinguish between a tensed and a tenseless sense of existence. I then show that while (what I call) absolute becoming must be regarded as an a priori ingredient of any physical theory presupposing an ontology of events (virtually all of the physics we know), relational relativistic becoming à la Stein could come into conflict with well-known physical theories (in particular quantum mechanics). This shows that the question raised in the title should be responded in the negative: physics can at best be invoked to show that relational becoming is not contradicted by presently-known physical theories, but cannot be invoked to provide positive, direct evidence for its mind-independence.
In the final part of the paper, I will discuss two possible ways to attack this conclusion, based on the connection of (relational) becoming with the issue of the direction of time. The first way is given by an attempt at explaining temporally asymmetric physical processes by the master asymmetry of becoming (which Stein proved to be coextensive with the relation of past-causal connectibility). The second way is to reverse the order of explanation and try to regard the physical asymmetries as being more fundamental than the asymmetry of causation.
I first argue that the special theory of relativity (in the standard four-vector formulation) requires the passage of time or temporal becoming.
But how is one to make sense of this conclusion? I suggest that an engaging picture of time in the special theory (a best fit of our pre-relativistic conception of time to this new theoretical context) combines at least the following ingredients:
the Passing of Time
There have been several sorts of philosophical argument that purport to show that the flow or passage of time cannot be, or is not, an intrinsic, fundamental asymmetry of temporal structure, metaphysically unrelated to the distribution of matter throughout space. I divide these arguments into the logical, scientific, and epistemological, and argue that none of the argument forms gives us reason to accept the conclusion. I then turn to the sorts of positive grounds one can have for accepting a fundamental passage of time, and in particular, how the passage of time can make itself manifest in scientific practice even if the fundamental laws of nature display Time Reversal Invariance.
on On the Passing of Time
What is the
Illusion of Temporal Flow?
We experience time as somehow flowing. B-theorists about time argue that this sense of times flow is an illusion. Before we can explain how the illusion arises, assuming it is one, we need to answer a prior question. It concerns the content of the illusion. By content of an illusion I mean the content of the state that misrepresents reality in an illusion. So in the Hering visual perception illusionin which straight parallel lines appear bentthe content is Such and such are bent lines. I argue in this paper is that it is difficult to find an analysis of the content of the temporal experience illusion that meets three conditions: (i) the analysis is a plausible rendering of the content of the illusion; (ii) we who suffer the illusion are capable of grasping the concepts constituting this content given what the B-theorist says are the temporal facts in reality; and (iii) the judgement employing this content is false. In short, prior to any question of explaining the illusion of temporal flowby appeal to facts about causation and memorythere is a serious issue about the semantical and ontological status of any such putative illusion.
on What is the Illusion of Temporal Flow?
Open Future for Presentism
Despite initial appearances a presentist can make room for a deep metaphysical difference between the nonexistent things in the past and the nonexistent things in the future. Neither past nor future things are; but for past things there are always truthmakers that settle whether those things were or were not, whereas for future things there are not always truthmakers that settle whether those things will or will not be. Or so a presentist could maintain. Furthermore, a presentist could maintain that there is a metaphysical dependence of what will be on what is and what was the case. It is possible that the direction of this dependence could take us at least some way towards an explanation of the passage of time.
The time at which some proposition is true is not in general the same as the time of occurrence of such events as the proposition is about. Likewise, I shall argue, the time at which something or event is real is not in general the same as the time at which it exists. Hence any events which are already real before they occur may be said to be fated. Fatalism undermines our responsibility for our actions. To avoid fatalism we should therefore deny the present reality of the future, or at least insist that its present reality is not determinate. Presentists go further and deny the present reality of anything that no longer exists. This sets up the well-known problem of trans-temporal relations such as causation. There are two rather drastic solutions to this problem, the denial of trans-temporal relations and Meinongianism (here understood as the thesis that there can be real states of affairs involving something that does not exist nonetheless having a property). Presentists such as Dean Zimmerman and Richard Swinburne have suggested a much more promising solution, namely that although nothing that no longer exists has present reality some thing that now exist also existed in the past, for they persist as the same things. Trans-temporal relations may then be analysed as properties of persisting things. Provided we have candidates for things that have always existed (God or the Universe) this solution seems acceptable. I shall argue however that the existence of persisting things itself implies fatalism unless the future is open (as presentists hold) in which case there is a successor problem. This successor problem is a special case of the more general puzzle of Shifting Reference, namely that the past events we now successfully refer to are not the same as any events we once referred to. My claim is that this renders incoherent the claim that we are responsible for what we shall do, a conclusion that is unacceptable to those presentists motivated by the way fatalism undermines responsibility.
and Chance Propensities
One major philosophical view of objective probabilities, or chances, describes these things in terms of propensities. E.g., the fact that the chance of heads, if you flip a coin fairly, is 1/2, is understood as a propensity, of degree 0.5, to produce the outcome heads. This propensity-property is understood to be a property of the combined coin + flipper system.
I will criticize the propensity view of objective chance by arguing that it is conceptually bound up with a long-discredited view of time, namely, A-series or flowing time. The thesis, in brief, is that if one tries to express the doctrine of propensity chances in a way that does not implicate flowing or passing time, one finds that it is essentially impossible. Therefore, since A-series time is metaphysically unacceptable, there is no metaphysically acceptable way to say what propensities are. Those who think that objective chance is nevertheless an important idea, must seek a different account of it.
Just in Time: Ontological Economy and the Status of
In the worlds of business and manufacturing, the Just-in-Time principle aims to eliminate unnecessary stockpiles of parts and raw materials. In the business of manufacturing worlds, Occams Razor plays an analogous rolea Just-in-Case principle for would-be worldmakers. In this paper, I argue that an efficiently constructed world is a world without dispositions. In an efficient world, dispositions belong on the epistemic side of the onticepistemic cut. I discuss the question as to whether this conclusion can be avoided by an appropriate temporal metaphysics, such as some version of presentism or the A-theory; but suggest that despite initial appearances, it is surprisingly insensitive to these issues. The main relevance of the philosophy of time lies on the epistemic rather than the metaphysical side of the issue, and concerns the question as to why the use of dispositional concepts is appropriate, for creatures with our temporal characteristics.
I extend into quantum mechanics a previous theory of mine that used statistical mechanics to explain away the intuition that the future is open while the past is fixed. Several outstanding problems with the classical version of the theory are thereby overcome so that the new theory can explain a significant part of the asymmetry between future and past. We also get interesting consequences for the nature of physical modalities. I contrast my argument for this modal structure and how it governs chance with arguments for propensities.
This event was supported by the Australian Research Council.
Last updated: 11.08.04