Murali Ramachandran

[full article, abstract in English; abstract in Lithuanian] Fred Dretske motivates his denial of epistemic closure by way of the thought that the warrant for the premises of a valid argument need not transfer to the argument’s conclusion. The failure-of-transfer-of-warrant strategy has also been used by advocates of epistemic closure as a foil to Michael McKinsey’s argument against the compatibility of first person authority and semantic externalism, and also to illuminate, more generally, why certain valid arguments appear ill-suited for the purpose of establishing their conclusions. This paper takes re-examines some of the central attempts to explain transmission-failure, and a central line of objection to the strategy from Begging-the-Question theorists. The ultimate goal of this paper is to promote a decidedly Dretskean explanation of the unpersuasiveness of the said arguments.

Lewis’s [1968] counterpart theory (LCT for short), motivated by his modal realism, made its appearance within a year of Chisholm’s modal paradox [1967]. We are not modal realists, but we argue that a satisfactory resolution to the paradox calls for a counterpart-theoretic (CT-)semantics. We make our case by showing that the Chandler–Salmon strategy of denying the S4 axiom [◊◊ψ →◊ψ] is inadequate to resolve the paradox – we take on Salmon’s attempts to defend that strategy against objects from Lewis and Williamson. We then consider three substantially different CT-approaches: Lewis’s LCT, Forbes’s (FCT), including his fuzzy version, and Ramachandran’s (RCT). We argue that the best approach is a mish-mash of FCT and RCT.

Both W9 and OP3‐4 were known to bind the receptor activator of NF‐κB ligand (RANKL), inhibiting osteoclastogenesis. Recently, both peptides were shown to stimulate osteoblast differentiation; however, the mechanism underlying the activity of these peptides remains to be clarified. A primary osteoblast culture showed that rapamycin, an mTORC1 inhibitor, which was recently demonstrated to be an important serine/threonine kinase for bone formation, inhibited the peptide‐induced alkaline phosphatase activity. Furthermore, both peptides promoted the phosphorylation of Akt and S6K1, an upstream molecule of mTORC1 and the effector molecule of mTORC1, respectively. In the in vivo calvarial defect model, W9 and OP3‐4 accelerated BMP‐2‐induced bone formation to a similar extent, which was confirmed by histomorphometric analyses using fluorescence images of undecalcified sections. Our data suggest that these RANKL‐binding peptides could stimulate the mTORC1 activity, which might play a role in the acceleration of BMP‐2‐induced bone regeneration by the RANKL‐binding peptides.

Hempel‘s paradox of the ravens, and his take on it, are meant to be understood as being restricted to situations where we have no additional background information. According to him, in the absence of any such information, observations of FGs confirm the hypothesis that all Fs are G. In this paper I argue against this principle by way of considering two other paradoxes of confirmation, Goodman‘s 'grue‘ paradox and the 'tacking‘ (or 'irrelevant conjunct‘) paradox. What these paradoxes reveal, I argue, is that a presumption of causal realism is required to ground any confirmation; but once we grant causal realism, we have no reason to accept the central principles giving rise to the paradoxes.

Advocates of occasional identity have two ways of interpreting putative cases of fission and fusion. One way—we call it the Creative view—takes fission to involve an object really dividing (or being replicated), thereby creating objects which would not otherwise have existed. The more ontologically parsimonious way takes fission to involve merely the ‘separation’ of objects that were identical before: strictly speaking, no object actually divides or is replicated, no new objects are created. In this paper we recommend the Creative approach as the best way of dealing with certain problem cases involving teletransportation. Our considerations yield novel takes on psychological-continuity theories of personal identity and survival, and on the puzzle of Theseus' ship.

André Gallois’ (1993) modified account of restrictedly rigid designators (RRDs) does indeed block the objection I made to his original account (Gallois 1986; Ramachandran 1992). But, as I shall now show, there is a deeper problem with his approach which his modification does not shake off. The problem stems from the truth of the following compatibility claim: (CC) A term’s restrictedly rigidly designating (RR-designating) an object x is compatible with it designating an object y in a world W where x exists but is distinct from y.1 It follows from (CC) that the necessary (contingent) truth of a sentence of the form “α is identical with β”, where “α” and “β” are RRDs of objects x and y respectively, does not require the necessary (contingent) identity of x and y. This is borne out by Gallois’ original example (see 1986, p. 58-63). Taking W to be the actual world, we have: (1) “Mary is identical with Mary” is necessarily true; yet “Mary” RR- designates Mary and Alice, which are only contingently identical. 1 I leave it to the reader to check that in Gallois’ own example (1986, p. 58), on the view he defends (pp. 62-63), and despite his modified characterisation of restricted rigidity, RDC# (1993, p. xx), “Mary” RR-designates Alice (as well as Mary) in W, but designates Mary and not A/ice in W1. Gallois has accepted this in correspondence. In light of (CC), while I agree with Gallois (1993, p. 153) that: (7) (a=b & ◊(a≠b)) → (∃x)(∃y)(x=y & ◊(x≠y)) is a theorem given RDC#, I dispute his defence of it (on p. 153). For, if (CC) is correct, the antecedent of (7) could be true even though a and b are identical in every world (where either exists)!

An ‘inverted’ reasoner is someone who finds the inferences we find easy, inversely difficult, and those that we find difficult, inversely easy. The notion was initially introduced by Christopher Cherniak in his book, Minimal Rationality, and appealed to by Stephen Stich in The Fragmentation of Reason. While a number of difficulties have been noted about what reasoning would amount to for such a reasoner, what has not been brought out in the literature is that such a reasoner is in fact logically impossible. This is what I hope to demonstrate in this paper

Aims. Saul Kripke’s (1977) argument defending Russell’s theory of (definite) descriptions (RTD) against the possible objection that Donnellan’s (1966) distinction between attributive and referential uses of descriptions marks a semantic ambiguity has been highly influential.1 Yet, as I hope you’ll be persuaded, Kripke’s line of reasoning— in particular, the ‘thought-experiment’ it involves—has not been duly explored. In section II, I argue that while Kripke’s argument does ward off a fairly ill-motivated ambiguity theory, it is far from clear whether it would succeed against more realistic candidates. If the central point I make in this regard is correct, it tells not only against Kripke’s argument but also against what has become a fairly orthodox line against the ambiguity thesis (as I shall call it). In section III, I compare Kripke’s defence of Russell with his ‘schmidentity’ argument (1980, p. 108), which involves essentially the same kind of thought-experiment. But, as I shall show, the latter argument contains an added twist which converts what otherwise would be merely a defence of one semantic theory into an attack against its rival. In section IV, I argue that the offensive strategy is unsound and attempt to locate its error. I conclude by drawing a (not unfamiliar) moral concerning the semantics—pragmatics distinction.

One of Strawson's objections to Russell's theory of descriptions is that what are intuitively natural and correct utterances of sentences involving incomplete descriptions come out false by RTD. Russellians have responded, not by challenging Strawson's view that these uses are natural and correct, but by embellishing RTD to accommodate these uses. I pursue an alternative line of attack: I argue that there are circumstances in which "we" would find utterances of such sentences unnatural and improper but "RTD" would sanction. So, RTD clashes with ordinary language, as Strawson suggests.

On David Lewis's original analysis of causation, c causes e only if c is linked to e by a chain of distinct events such that each event in the chain (counter-factually) depends on the former one. But this requirement precludes the possibility of late pre-emptive causation, of causation by fragile events, and of indeterministic causation. Lewis proposes three different strategies for accommodating these three kinds of cases, but none of these turn out to be satisfactory. I offer a single analysis of causation that resolves these problems in one go but which respects Lewis's initial insights. One distinctive feature of my account is that it accommodates indeterministic causation without resorting to probabilities.