William Seager

The apparent 'flow' of time is one of its most mysterious features, and one which discomforts both scientists and philosophers. One of the most striking assaults upon it is McTaggart's argument that the idea of temporal flow is demonstratively incoherent. In this paper I first urge that the idea of temporal flow is an important part of our intuitive understanding of time, underpinning several of our notions about rationality and time. Second, I try to undercut McTaggart's argument by showing that it is not temporal flow which is illusory but rather the vicious regress McTaggart saw in that idea. A steadfast clinging to the notion of now, along with an analysis of McTaggart's argument reveals that the regress halts after but two steps.

The goal of standard semantics is to provide truth conditions for the sentences of a given language. Probabilistic Semantics does not share this aim; it might be said instead, if rather cryptically, that Probabilistic Semantics aims to provide belief conditions.The central and guiding idea of Probabilistic Semantics is that each rational individual has ‘within’ him or her a personal subjective probability function. The output of the function when given a certain sentence as input represents the degree of likelihood which the individual would assign to that sentence. One can characterize these functions via a set of axioms, and in the terms of this defined structure develop probabilistic analogues of all important semantical notions. Then, dealing with ‘being given probability 1’ instead of ‘truth,’ one can proceed to give a completely adequate semantics for the particular language under consideration. The axioms delimiting the class of probability functions are, in fact, chosen with this goal and language in mind.

This note aims to make more familiar to philosophers yet another bizarre quantum mechanical effect with disturbing metaphysical implications. It is possible to modify the classic double-slit experiment so that one can register the path of a particle to determine which slit it passes through, and then erase this registered information so that the interference effects which would normally disappear upon registration of the "which path" information are reconstituted. Thus the "trajectory" of particles can be effected by temporally and spatially distant operations on the slit detectors. Nonetheless, no untoward effects (such as superluminal signalling) can result from the operation of the eraser

Brook and Raymont do not assert that self-representing representations are sufficient to generate consciousness, but they do assert that they are necessary, at least in the sense that self-representation provides the most plausible mechanism for generating conscious mental states. I argue that a first-order approach to consciousness is equally capable of accounting for the putative features of consciousness which are supposed to favor the self-representational account. If nothing is gained the simplicity of the first-order theory counts in its favor. I also advance a speculative proposal that we are never aware of any distinctively mental attributes of our own states of consciousness except via an independent act of reflective conceptualization, although this goes rather farther than the first-order theory strictly requires.

Jerry Fodor has recently proposed a new entry into the list of information based approaches to semantic content aimed at explicating the general notion of representation for both mental states and linguistic tokens. The basic idea is that a token means what causes its production. The burden of the theory is to select the proper cause from the sea of causal influences which aid in generating any token while at the same time avoiding the absurdity of everything's being literally meaningful. I argue that a detailed examination of the theory reveals that neither burden can be successfully shouldered.

Our knowledge forms a highly interconnected and dynamically changing body of propositions. One obviously important way that knowledge changes is via rational inference, based either upon new insight into the content of what we already know or upon new knowledge provided by the senses. The most obvious codification of the acceptability of inference driven knowledge growth is the so-called known entailment closure principle, the principle that if S knows that p and knows that p implies q then S knows that q, or, more formally.

Donald Davidson espouses two fundamental theses about the individuation of mental events. The thesis of causal individuation asserts that sameness of cause and effect is sufficient and necessary for event identity. The thesis of content individuation gives only a sufficient condition for difference of mental events: if e and f have different contents then they are different mental events. I argue that given these theses, psychological externalism--the view that mental content is determined by factors external to the subject of the relevant mental events--entails that the token identity theory is false

The doctrine of physicalism can be roughly spelled out simply as the claim that the physical state of the world determines the total state of the world. However, since there are many forms of determination, a somewhat more precise characterization is needed. One obvious problem with the simple formulation is that the traditional doctrine of epiphenomenalism holds that the mental is determined by the physical (and epiphenomenalists need not assert that there are any properties except mental and physical ones, so one can freely add to epiphenomenalism the claim that everything is determined by the physical state of the world). However, the orthodox view, which seems obviously correct, is that physicalists would and should balk at the claim that epiphenomenalism is a form of physicalism. The philosophical zombie thought experiment vividly reveals exactly why epiphenomenalism is not a version of physicalism. According to traditional epiphenomenalism the determination relation in question is causation, and causal relations do not hold with full necessity. They hold with at most nomological necessity. Thus there is a possible world, w, in which the causal laws (or, if one prefers a more Humean approach, where the cosmic regularities) are different in such a way that the physical states which in the actual world cause mental states either cause no mental states at all in w (the zombie option) or cause aberrant mental states (the inverted spectrum option). Why should the physicalist care about this ‘mere possibility’? Because it shows that the mental can vary independently of the physical and there can be no better demonstration of ontological distinctness 1 than independent variation. Therefore, physicalism requires that the sort of determination at issue must exhibit maximum modal force; it must be absolutely impossible for the mental to vary without attendant, determining physical variation (let us label this relation ‘logical determination’). I think the best way to state physicalism which meets this constraint is in terms of what are called minimal physical duplicates (MPDs) of possible worlds (an approach pioneered by David Lewis, see Lewis (1983b); see also Jackson (1998) and Chalmers and Jackson (2001))..