Roy Sorensen

An ill-informed reading of Adam Ferguson 's epitaph has given me an idea for securing posthumous recognition. Consider philosophers in the year 2201 who read my epitaph: ‘Here lies Roy Sorensen who will be long remembered for his paradoxes’. If these future scholars remember me, then well and good. If they do not remember me, my epitaph will appear to be rendered false by their failure to recall me. Suppose the poignancy of this self-defeat leads my epitaph to be widely repeated. I thereby acquire ignominy as the forgotten philosopher. But wait! Eventually someone will notice that no one can remember that Roy Sorensen is forgotten. For if someone did remember that Roy Sorensen is forgotten, then he would be forgotten—not remembered. After all, memory implies truth. Thus the self-defeating aspect of my epitaph is itself self-defeating! The happy ending is that my epitaph becomes a self-fulfilling prophesy by a curious kind of double-negation

Lake Tanganiyka has lefty and righty cichlid fish that show there can be natural selection for a trait over its mirror image counterpart.This raises the question Can there be biological selection of a whole organism over its mirror image counterpart? That is, could the fitness of a fish be altered by simply changing it into its own enantaniomorph? My answer is no. I present Flatlander thought experiment to demonstrate that mirror imagecounterparts are duplicates because they only differ in how they happen to be oriented in space. The counterparts have the same intrinsic properties and are in the same environment,so there can be no difference in fitness.

This is a defense and extension of Stephen Yablo's claim that self-reference is completely inessential to the liar paradox. An infinite sequence of sentences of the form 'None of these subsequent sentences are true' generates the same instability in assigning truth values. I argue Yablo's technique of substituting infinity for self-reference applies to all so-called 'self-referential' paradoxes. A representative sample is provided which includes counterparts of the preface paradox, Pseudo-Scotus's validity paradox, the Knower, and other enigmas of the genre. I rebut objections that Yablo's paradox is not a genuine liar by constructing a sequence of liars that blend into Yablo's paradox. I rebut objections that Yablo's liar has hidden self-reference with a distinction between attributive and referential self-reference and appeals to Gregory Chaitin's algorithmic information theory. The paper concludes with comments on the mystique of self-reference.

An electoral evaluation of a set of expert opinions proceeds by treating the experts as voters. Although this method allows us to formalise our naive views about how to take expert advice, the formalisations are plagued by paradoxes which parallel those found in literature on social aggregation devices. This parallel suggests that our naive views about taking expert advice are in as much need of revision as our naive views about deriving group preferences from individual preferences. * I am indebted to Joseph Hanna for a number of criticisms and corrections to a previous draft.

Stereotypically, computation involves intrinsic changes to the medium of representation: writing new symbols, erasing old symbols, turning gears, flipping switches, sliding abacus beads. Perspectival computation leaves the original inscriptions untouched. The problem solver obtains the output by merely alters his orientation toward the input. There is no rewriting or copying of the input inscriptions; the output inscriptions are numerically identical to the input inscriptions. This suggests a loophole through some of the computational limits apparently imposed by physics. There can be symbol manipulation without inscription manipulation because symbols are complex objects that have manipulatable elements besides their inscriptions. Since a written symbol is an ordered pair of consisting of a shape and the reader's orientation to that inscription, the symbol can be changed by changing the orientation rather than inscription. Although there are the usual physical limits associated with reading the answer, the computation is itself instantaneous. This is true even when the sub-calculations are algorithmically complex, exponentially increasing or even infinite

Poindexter points and asserts `That is Clinton''. But it is vague as to whether he pointed at Clinton or pointed at the more salient man, Gore. Since the vagueness only occurs at the level of reference fixing, the content of the identity proposition is precise. Indeed, it is either a necessary truth or a necessary falsehood. Since Poindexter''s utterance has a hidden truth value by virtue of vagueness, it increases the plausibility of epistemicism. Epistemicism says that vague statements have hidden truth values. If a precise statement can have a hidden truth value conferred indirectly by vaguesness, then a vague statement can have a hidden truth value directly by its own vagueness.

Do we need light to see? I argue that the black experience of a man in a perfectly dark cave is a representation of an absence of light, not an absence of representation. There is certainly a difference between his perceptual knowledge and that of his blind companion. Only the sighted man can tell whether the cave is dark just by looking. But perhaps he is merely inferring darkness from his failure to see. To get an unambiguous answer, I switch the focus from perceptual knowledge to non-epistemic seeing. My conclusion is that we see even in the limiting case of absolute darkness - regardless of whether we believe we are seeing. We see little of pratical interest. But in terms of basic information, we see about as much as we do when the lights are on. Depending on what has gone before and after, we may even see ordinary objects

Consider the beginningless sequence: ... being less than 0.01 grams, being less than 0.1 grams, being less than 1 gram, being less than 10 grams ... There is no super-determinate in this chain. Just as the possibility of bottomless constitution shows that there may be no fundamental layer of reality with respect to objects , the possibility of bottomless determination shows that there may be no fundamental level of reality with respect to properties . This possibility supports Stephen Yablo's proportionality principle that the cause of an event is the most specific property that makes a difference

Verisimilitude has the potential to deepen the understanding of mathematical progress, the principle of charity, and the psychology of regret. One obstacle is the widely held belief that two statements can vary in truthlikeness only if they vary in what they entail. This obstacle is removed with four types of counterexamples. The first concerns necessarily coextensive measurements that differ only with respect to their units (specifically length, area, and volume). The second class ofcounterexamples is composed of mathematical falsehoods. The third class features inconsistent scientific theories. The fourth class of cases features statements that are instructive but meaningless