My dissertation deals with the Master Argument of Diodorus Cronus, a contemporary of Aristotle's. The argument was one of the most famous pieces of temporal and modal reasoning in ancient philosophy. It purports to prove that a proposition is possible if and only if it is true or will be true. The argument runs as follows: Everything that is past and true is necessary; The impossible does not follow the possible; Therefore, nothing is possible which (...) neither is nor will be true. Unfortunately, all accounts of the Master that have survived are so sketchy that we cannot determine whether the argument is valid or not. ;Several reconstructions of Diodorus' argument have been proposed. The purpose of the reconstructions is to show, using the resources of modal and tense logics, that the argument is valid. I analyze and critique most of these proposals, arguing in the final chapter for a new reconstruction which I believe to be more defensible than existing ones. ;The Master Argument is important for several reasons. It elicited much discussion among ancient philosophers and logicians both because of its reduction of modal logic to tense logic and its bearing on the free will/determinism debate. But, its influence also extends to contemporary philosophy and logic. In the 1950s and 60s, the Master inspired formal work on Diodorean systems. Much of the work on the calculus of tenses, e.g., by Prior, was undertaken in view of investigating Diodorus' argument. Finally, the literature that the argument has spawned has enriched and deepened our understanding of the connections between matters modal and temporal. (shrink)

This paper discusses the 'master argument' of diodorus cronos from a semantic perspective. An argument is developed which suggests that proposition (1), 'every proposition true about the past is necessary', May have provided the principal motivation for diodorus denial of proposition (3), I.E., His equation of possibility with present-Or-Future truth. It is noted that (1) and (3) are jointly inconsistent only given the assumption of a linear ordering of time. It is further noted that (...) class='Hi'>diodorus' fatalism "could" be employed to justify this additional assumption. However, To then use the conclusion of the 'master' to argue for fatalism would obviously be circular. I suspect, Rather, That diodorus' assumption of temporal linearity was implicit and uncritical. (shrink)

The article deals with some current pioneering formal reconstructions and interpretations of the problem well known in antiquity as The Master Argument. This problem is concerning with enrichment of formal logical systems with modal and temporal notions. The opening topic is devoted to reconstruction of Arthur Prior. while the other here included approach to the problem arc mostly reactions. revisions or additions to this one.

On prior's reconstruction, The master argument of diodorus contains an equivocation and so is invalid for one class of diodorean "propositions." but diodorus knew of such "propositions" and an argument in his treatment of motion can be used to bring them under the master argument's sway. Also, Despite the consensus of antiquity, The master argument does not commit diodorus to determinism, Although it commits him to non-Deterministic theses which can be (...) easily misinterpreted as deterministic. (shrink)

Diodorus cronus was a megaric logician who was reputed to have derived from uncontroversial premises the surprising conclusion that the possible is that which either is or will be the case. Versions of his lost argument have been reconstructed recently by prior, Hintikka, And rescher. I analyze and compare these versions and argue that none of them forms a sound argument.

The Master Argument, recorded by Epictetus, indicates that Diodorus had deduced a contradiction from the conjoint assertion of three propositions. The Argument, which has to do with necessity and contingency and therefore with freedom, has attracted the attention of logicians above all. There have been many attempts at reconstructing it in logical terms, without excessive worry about historical plausibility and with the foregone conclusion that it was sophistic since it directly imperilled our common sense notion of (...) freedom. This text takes exception to recent tradition, translating the propositions into logical terms. The propositions figuring in The Master Argument are interpreted in terms of temporal modal logic where both the modalities and the statements they govern have chronological indices. This means that the force of the argument comes not from purely logical or modal considerations, but from our experience of time. (shrink)

Preliminaries: Terminology and Notation We may make a distinction between temporally definite and temporally indefinite sentences. ...

The well known Master Argument of ancient Stoic logician Diodorus Cronus is an argument in favour of the philosophical doctrine of fatalism. Perhaps in antiquity this argument was a subject of the most celebrated controversy about temporal truth and modality. This argument is a subject of logical analysis, especially in connection with temporal logic, also today. 1 The most elegant tense-logical formulation of the Master Argument has been given by A. N. Prior. (...) Discreteness and irreflexivity of time are semantical assumptions of Prior’s formulation of the argument. The assumption of discreness is troublesome. 2 The problem of this assumption is a subject of M. J. White’s paper “The Necessity of the Past and ModalTense Logic Incompleteness”. 3. (shrink)

A Master-like argument, in the usage of the present paper, is an argument that employs a reductio ad impossibile principle to transmit the necessity of what are or become past truths to the remainder of time by means of necessary conditionals of some sort. The conclusion of such an argument is some no-unactualized-possibilities principle. This paper argues that the formulation of a Master-like argument by A. N. Prior in a mixed modal temporal propositional logic (...) introduces certain artifacts into the logical analysis of the argument. One of these, a principle of temporal discreteness, is not essential to a Master-like argument. Another, a principle of forwards temporal linearity, is technically essential; but it is usually tacitly presupposed by the necessary temporal conditionals employed to 'tie together' past and future time in less formal accounts of Master-like arguments. (shrink)

In the fourteenth century, Duns Scotus suggested that the proper analysis of modality required not just moments of time but also “moments of nature”. In making this suggestion, he broke with an influential view first presented by Diodorus in the early Hellenistic period, and might even be said to have been the inventor of “possible worlds”. In this essay we take Scotus’ suggestion seriously devising first a double-index logic and then introducing the temporal order. Finally, using the temporal order, (...) we define a modal order. This allows us to present modal logic without the usual interpretive questions arising concerning the relation called variously ‘accessibility’, ‘alternativeness’, and, ‘relative possibility.’ The system in which this analysis is done is one of those which have come to be called a hybrid logic. (shrink)

Chrysippus claims that some propositions perish. including some true conditionals whose consequent is impossible and antecedent is possible, to which he appeals against Diodorus?s Master Argument. On the standard interpretation. perished propositions lack truth values. and these conditionals are true at the same time as their antecedents arc possible and consequents impossible. But perished propositions are false, and Chrysippus?s conditionals are true when their antecedent and consequent arc possible, and false when their antecedent is possible and consequent (...) impossible. The claim of the Master Argument that Chrysippus rejects, then, is stronger ihan usually supposed. (shrink)

This book is an English version of a book published in 1984 in French, the aim of which was to give a reconstruction of Diodorus Cronus's Master Argument, together with a historical analysis of some of the central modal notions on which it draws. In preparing the English text, Vuillemin has made some changes to the logic of his reconstruction of Diodorus's Argument and added an epilogue. The Master Argument consisted of three premises: (...) Every past truth is necessary, The impossible does not follow from the possible, and Something is possible which neither is nor will be true. Diodorus claimed that these premises are inconsistent, and purported to derive the negation of the third premise, which is plausibly to be identified with the principle of plenitude, from the first two premises. (shrink)

We may distinguish between two ways of understanding tense-logical formulae, depending on whether we construe tense operators as operators on sentences or on predicates. Bearing this distinction in mind helps us formalise the premisses of Diodorus Cronus' Master Argument correctly, and give a formal reconstruction of the Argument itself.

The master argument posits a metaphysical thesis: Diodorus does away with Aristotle’s dunamis understood as a power simultaneously oriented toward being and non-being and proclaims that possibilities that fail to actualize are simply nothing. My contention is that this claim is not a mere application of Diodorus’ contribution to modal logic. Rather, Diodorus creates an ontologico-temporal concept of possibility and impossibility. Diodorus envisions the future as the past that the future will become. Since what (...) will have been can never be the accomplishment of a possibility that did not obtain, and since the future is destined to become past, any futural possibility that doesn’t actualize is neither futural nor even possible. (shrink)

The article discusses the biographical and doxographical evidence for Diodorus Cronus, a prominent and influential figure at the start of Hellenistic philosophy. Special emphasis is given to Diodorus’ logic, as well to his controversy with Philo the Dialectician over the truth-criteria for the conditional as to his Master argument, concerning modal notions.

Essays on Aristotle's Sea-Battle, Lazy Argument, Argument Reaper, Diodorus' Master Argument -/- The book is devoted to the ancient logical theories, reconstruction of their semantic proprieties and possibilities of their interpretation by modern logical tools. The Ancient arguments are frequently misunderstood in modern interpretations since authors usually have tendency to ignore their historical proprieties and theoretical background what usually leads to a quite inappropriate picture of the argument’s original form and mission. Author’s primary intention (...) was to draw attention to the complexity of some historical arguments and to the theoretical context in which arguments were created, circulated, developed, and finally tuned. Four well-known ancient arguments – with a common central subject related to the future contingencies problem – are reconstructed from available historical sources: “The Sea Battle”, which is drawn from Aristotle’s treatise De Interpretatione; two arguments, usually ascribed to the Stoics, “The Lazy Argument” and “The Reaper”; “The Master Argument” of the Megarian philosopher Diodorus. Arguments are linguistically and semantically detaily analyzed, formally presented by reflecting some relevant corresponding hypotheses based on physical or logical theories of their ancient authors, and finally covered by appropriate logical tools familiar to a modern reader. Two appendices are added at the closing part of the book. One covering some assumptions relevant for understanding of rival streams in ancient theories of meaning related to the nature of names and naming; the other is devoted to the ancient understanding of logical proposition and attempts to find an adequate Latin translation of the Greek delicate philosophical term “ἀξίωμα”. (shrink)

ABSTRACT: The modal systems of the Stoic logician Chrysippus and the two Hellenistic logicians Philo and Diodorus Cronus have survived in a fragmentary state in several sources. From these it is clear that Chrysippus was acquainted with Philo’s and Diodorus’ modal notions, and also that he developed his own in contrast of Diodorus’ and in some way incorporated Philo’s. The goal of this paper is to reconstruct the three modal systems, including their modal definitions and modal theorems, (...) and to make clear the exact relations between them; moreover, to elucidate the philosophical reasons that may have led Chrysippus to modify his predessors’ modal concept in the way he did. It becomes apparent that Chrysippus skillfully combined Philo’s and Diodorus’ modal notions, with making only a minimal change to Diodorus’ concept of possibility; and that he thus obtained a modal system of modalities (logical and physical) which fit perfectly fit into Stoic philosophy. (shrink)

ABSTRACT: Summary presentation of the surviving logic theories of Philo the Dialectician (aka Philo of Megara) and Diodorus Cronus, including some general remarks on propositional logical elements in their logic, a presentation of their theories of the conditional and a presentation of their modal theories, including a brief suggestion for a solution of the Master Argument.

The noctes Atticae of Aulus Gellius contain almost all the ancient paradoxes. Nevertheless, in comparison with his philosophical sources, the author shows a shift in the perspective of his approach. He analyses the `master argument' of Diodorus Chronus only from an ethical point of view and, among the seven paradoxes attributed to Eubulides of Milet, he quotes the `heap' as an absurdity (absurdum), the `horned one' and the `not-someone' as a trap (captio), the `liar' as a sophism (...) (sophisma). Following the advice of Cynics, Gellius mistrusts deceptive manoeuvres, which highlight gaps in binary logic. At the same time, however, he is interested in argumentative structures, which lead one of two opponents on to victory. The extensive report of the quarrel between Protagoras and Evathlus, and many observations of Gellius on convertible forms of reasoning in literary texts fall within this rhetorical field. (shrink)

Almost all the chapters of this book have appeared earlier as separate articles in American and Finnish journals between 1957 and 1971, but are now reprinted together as dealing with Aristotle’s theory of modal notions and its underlying doctrines and assumptions. Recital of the chapter headings illustrates the scope of the book: "Aristotle and the Ambiguity of Ambiguity" ; "Aristotle’s Different Possibilities" ; "On the Interpretation of De Interpretatione 12-13" ; "Time, Truth and Knowledge in Aristotle and Other Greek Philosophers" (...) ; "Aristotle on the Realization of Possibilities in Time" ; "Aristotelian Infinity" ; "On Aristotle’s Modal Syllogistic" ; "The Once and Future Sea Fight: Aristotle’s Discussion of Future Contingents in De Interpretatione 9" ; and "Aristotle and the ‘Master Argument’ of Diodorus". The volume ends with "Index of Texts" cited from Aristotle and other Greek authors and "General Index". (shrink)

This text is expository. We explain Gödel’s ‘Master Argument’ for incompleteness as distinguished from the 'official' proof of his 1931 paper, highlight its attractions and limitations, and explain how some of the limitations may be transcended by putting it in a more abstract form that makes no reference to truth.

It is argued that reconstructions of the so-called ‘Master Argument’ of Dideros Cronos to the effect that possibility should be understood as present or future truth, essentially relies on two axioms: i) that every true proposition concerning the past is necessary, and ii) that it follows necessarily from a proposition being true that it always has been the case that it would be true. It is furthermore argued that these two axioms are inconsistent in the sense that any (...) tense/modal semantics which incorporates both collapses either modally (fails to distinguish between truth simpliciter and modalised truth) or temporally (fails to offer a plausible semantical account for propositions about the future). This finding is, furthermore, taken as indicator for the more generel claim that there are principled difficulties involved in construing semantics for combined tense/modal logical systems. (shrink)

The main idea animating the present paper is that the general aim of debates, such as the one involving the notorious case of the Master Argument, is the ponderation of logical principles by confronting them with some set of assertions and other endorsed principles on the meaning explanation of connectives, quantifiers and modality. As suggested by Seel (2017), the point of the specific case of the MA is about examining Aristotle’s notion of possibility – as implemented by the (...) Possibility Principle (i.e., If it is necessary that if A then B, then B is possible if A is) and the Possibility Rule (i.e., If A is possible, and if B follows from the assumption of A, then B is is possible) in the context of a dialectical debate where it has been asserted that a given proposition is possible, even it is neither true now nor it will ever be, and where at the same time the irrevocability of the past has been endorsed. This suggests to study the MA debate in a setting based on Marion’s (2020) reconstruction of Aristotle’s Dialectical Bouts, adapted to propositions affected by modalities. The setting of Dialectical Bouts for the MA proposed includes•Propositions affected by Reichenbach’s (1948, § 5) three-folded temporal reference, namely: the point of speech S, the point of reference R and the point of the event E. This constitutes our take on Vuillemin’s (1977, 1979, 1984, 1996) suggestion of a “double indexation”.•The dialogical meaning explanation for modalities understood as involving hypotheticals. •The dialogical rules that settle the commitments undertaken when endorsing Aristotle’s Possibility Principle. In fact, in relation to the notion of possibility at work in Vuillemin’s (1996) reconstruction we explored different formulations of the Possibility Rule. Still, there remains a dearth of researches confronting the different formulations of the Possibility Rule with the texts studied by Crubellier (2010) and Rosen and Malink (2012). More generally and coming back to my remarks above, one of the most fruitful insights that can be gained from Vuillemin’s writings on the MA, is that such kind of debates provide an instance of a general pattern for reasoning that I shall call Dialectical Bouts of Material Admissibility (BMA). The rationale behind such kind of argumentation-pattern is to examine the incorporation of new (epistemological, ontological or logical) principles against the background of the commitments undertaken by endorsing a specific set of assertions and meaning explanations. They display the kind of abductive procedure stressed by Crubellier’s (2014) study of syllogism. Under this perspective Ebbinghaus’s (1964) casting of the inferential moves that reduce imperfect syllogisms to perfect ones as implementing an admissibility procedure, represents a logical generalization of the material procedures at stake in the Dialectical Bouts of Material Admissibility. Furthermore if, as stressed by Duthil-Novaes (2005) Medieval Obligations represent a development of Aristotelian Bouts aimed at the ludic exercise of consistency maintenance, DMA should be rather linked to the Islamic tradition of dialectical theory [jadal, munāẓara, ādāb al-baḥth], aimed at the epistemological task of what Young (2017) calls the forging of principles, including legal and deontic ones. In a more contemporary setting, DMA can be related to Brandom’s (2000, pp. 66-77) considerations on Non-Conservative Extensions, where the point of dialectical procedures is put under public Socratic scrutiny the discovery and elucidation of concepts. This general point on Dialectical Bouts of Material Admissibility can be seen as underlying Vuillemin’s project of linking the study of the MA with the classification of philosophical systems.The present paper does not contain a fully developed study on such Dialectical Bouts, but it is rather is an invitation to pick up the gauntlet that Jules Vuillemin threw into the ring. (shrink)

We can find in the passages that set out the Master Argument a precursor to the paradox of knowability. That paradox shows that if all truths are knowable, all truths are known. Similarly, Berkeley might be read as proposing that if all sensible objects are (distinctly) conceivable, then all sensible objects are conceived.

I will discuss the so-called “Master Argument” attributed to Diodorus Cronos in the light of some contemporary speculations on indexicals. In one version, this argument goes as follows: Premise 1. The past, relative to any time t, is necessary. Premise 2. The impossible cannot follow from the possible. Therefore.

The paper deals with the question of how the claim that nothing impossible follows from what is possible, which serves as the second premise of Diodorus' Master Argument, should be properly understood. In the first part I attempt to show that the interpretation of the thesis in the form of the following implication as suggested by R. Gaskin is not tenable: "If A and non-A follows from {A} plus the set Sigma, then not possible A follows from (...) Sigma alone" In the second part I discuss a reconstruction of the Master Argument which adopts A. N. Prior's interpretation of the said thesis in form of the modal-logical theorem "If it is necessary that , then " but modifies Prior's suggested reconstruction in a way which should make it more plausible. (shrink)

Sententialism is the view that intensional positions in natural languages occur within clausal complements only. According to proponents of this view, intensional transitive verbs such as 'want', 'seek' or 'resemble' are actually propositional attitude verbs in disguise. I argue that 'conceive' cannot fit this mould: conceiving-of is not reducible to conceiving-that. I offer a new diagnosis of where Berkeley's 'master argument' goes astray, analysing what is odd about saying that Hylas conceives a tree which is not conceived. A (...) sententialist semantics cannot account for the absurdity in attitude ascriptions of this type: we need to acknowledge irreducibly non-propositional conceiving. (shrink)

My purpose is to compare Berkeley’s and Gentile’s idealism, interpreting Berkeley’s Treatise, §§22–23, and Gentile’s reading of this passage. The Italian philosopher finds in Berkeley’s master argument the original source of the true idealistic way of thinking, but he believes that Berkeley has not been sufficiently consistent in deducing all the consequences from his new principle. This criticism is the ground of Gentile’s actual idealism. Comparing the two positions is very instructive both to elucidate the general issue of (...) idealism and to understand Berkeley’s philosophy. (shrink)

In De Trinitate 10, Augustine offers an argument that seemingly proceeds from certain premises about self-knowledge to the conclusion that the mind is incorporeal. Although the argument has sometimes been compared to later Cartesian arguments, it has received relatively little philosophical attention. In this paper, I offer a detailed analysis and original interpretation of Augustine's argument and argue that it is not vulnerable to some of the main objections which have been raised against it. I go on (...) to argue that while an important part of Augustine's argument does face several hitherto neglected objections, Augustine's ultimate case for the incorporeality of the mind is somewhat different and more successful than one might initially think. (shrink)

The past 25 years have witnessed a vigorous discussion of an argument directed against the compatibilist approach to free will and responsibility. This reasoning, variously called the “consequence argument,” the “incompatibility argument,” and the “unavoidability argument,” may be expressed informally as follows: If determinism is true then whatever happens is a consequence of past events and laws over which we have no control and which we are unable to prevent. But whatever is a consequence of what’s (...) beyond our control is not itself under our control. Therefore, if determinism is true then nothing that happens is under our control, including our own actions and thoughts. Instead, everything we do and think, everything that happens to us and within us, is akin to the vibration of a piano string upon being struck, with the past as pianist, and could not be otherwise than it is. While a number of philosophers take this reasoning to crush the prospects of compatibilism, others challenge its assumption that unavoidability “transfers” from sufficient condition to necessary condition or from cause to effect. The ensuing debate has occasionally been vitriolic— Hume once remarked that the free will issue is “the most contentious question of metaphysics, the most contentious science”—yet undeniably fruitful in generating more detailed examinations of ability and practical freedom. Whether we incline towards compatibilism or 2 incompatibilism, this latter development is likely to be of lasting value. As a compatibilist, I believe that the consequence argument fails to prove incompatibilism, and here I will develop criticisms of it that, for the most part, are already in the existing literature. Although a short essay cannot provide the theoretical account of practical freedom needed to underpin and justify this compatibilist critique, it will clarify the tasks that lie ahead. (shrink)

One of Berkeley's best-known arguments for the view that there are no material objects is the so-called Master Argument. There are several good critical discussions of it. That invites the question: is there anything new to say? Well, it will be argued, there are a few things to say. First, although refutations by logical analogy have been advanced against the Master Argument, the strongest such refutation, one which demonstrates its incoherence, has not been. It is here. (...) Second, there are few formal reconstructions of the Master Argument – the great majority of discussions treat it discursively – but a formal reconstruction, and one not found elsewhere, is offered here. Third, the formal reconstruction makes possible identification of the essential mistake of the argument. That mistake is equivocation. The common complaint that Berkeley illicitly introduces the act of conceiving into the content of the concept conceived is not quite correct; but to the extent that it is correct, it's explicable in terms of an underlying equivocation. Fourth, the article presupposes no acquaintance with Berkeley's work and is written in a conversational, easy-to-read style. Given that Berkeley himself wrote in a similar style, he could at least agree that the fourth point is a merit of the article. (shrink)

The source-criticism2 of Diodorus XVI has been dominated by the principle of argument from detail. Thus, if two details in Diodorus' text are found to conflict, they are assumed to derive from different sources and, if similar, from the same source; and, where a fragment of an ancient historian is found to resemble a passage in Diodorus, that historian is assumed to be the source employed by Diodorus in that passage; finally, when a sufficient mosaic (...) of such details is pieced together, general divisions are drawn to embrace each separate detail. But this principle is of questionable value: for it implies the tacit assumption that Diodorus made no mistake in compressing or transcribing detail, added no colour himself, and could only have derived a given detail, described in a given manner, from the one ancient historian whose description of that detail is preserved. When one remembers that Diodorus is a careless and unintelligent compiler of a compendious narrative, who aimed like Ephorus at lending each book a unity, and that the fragments of the many historians whom Diodorus may have excerpted are very scanty, it is clear that this principle admits of a large margin of error. (shrink)

This is a commentary on Adrian Heathcote’s interesting paper ‘Hume’s Master Argument’. Heathcote contends that No-Ought-From-Is is primarily a logical thesis, a ban on Is/Ought inferences which Hume derives from the logic of Ockham. NOFI is thus a variation on what Heathcote calls ‘Hume’s Master Argument’, which he also deploys to prove that conclusions about the future (and therefore a-temporal generalizations) cannot be derived by reason from premises about the past, and that conclusions about external objects (...) or other minds cannot be derived by reason from premises about impressions. Heathcote raises an important question. Having (apparently) argued that our inductive inferences are not justified by reason, Hume puts them down to Custom, and seems to suggest that we OUGHT to indulge this propensity but NOt the superstitious propensities that lead to religious belief. (Query: Why is it right to indulge one non-rational propensity but not the others?) Finally Heathcote argues that just as there are valid, but not formally valid, arguments taking us from claims about inferential relations to claims about what we ought to believe, so there may be valid, but not formally valid, arguments taking us from factual claims about some situation to claims about what we ought to do. -/- I reply that Hume does indeed have a Master Argument and that it does rely on logical principles but not on the logic of Ockham which had been largely forgotten by Hume’s day. Instead Hume relies on the idea widely believed in the 18th Century and taught to Hume at Edinburgh by his logic Professor Colin Drummond, that in a logically valid argument the conclusion is contained in the premises. I reconstruct Hume’s Master Argument using this principle. I draw a careful distinction between two theses: 1) that we cannot get from non-moral premises to moral conclusions with the aid of logic alone and 2) that we cannot get from non-moral premises to moral conclusions with aid of analytic bridge principles. Hume believed the first but not the second. What then is the role of NOFI in the larger argument of the Treatise? To show that the truths of ethics cannot be derived via logic from self-evident truths of some other kind and thus that they are not demonstrable. How can we make sense of Hume’s apparent belief that it is sometimes right to transcend reason and sometimes not? In the case of Custom, we live in a world governed by causal regularities, and, in such a world, induction is in fact a fairly reliable belief-forming mechanism. Thus a suitably qualified spectator (one aware of the kind of world we live in) would tend to approve of indulging it, even if it cannot be justified by reason. However, our superstitious propensities are (and can be known to be) unreliable, since they produce different and inconsistent results in different people. Thus it is it is wrong (something a suitably qualified spectator would disapprove of) to indulge the faculty of Superstition. I also take issue with Heathcote’s penchant for valid, but not formally valid, inferences. I supply the missing premises for Heathcote’s Is/Ought inferences and argue that they are either not true or not necessary. (shrink)

Berkeley’s ‘master argument’ for idealism has been the subject of extensive criticism. Two of his strongest critics, A.N. Prior and J.L. Mackie, argue that due to various logical confusions on the part of Berkeley, the master argument fails to establish his idealist conclusion. Prior argues that Berkeley’s argument ‘proves too little’ in its conclusion, while Mackie contends that Berkeley confuses two different kinds of self-refutation in his argument. This paper proposes a defence of the (...) master argument based on intuitionistic argument. It begins by giving a brief exposition of the master argument and Prior's and Mackie's criticism. The following section explains why we might read the master argument along intuitionistic lines. The final section demonstrates that, according to intuitionistic logic, Berkeley's argument withstands the criticisms of Prior and Mackie. (shrink)

In my article "berkeley's master argument" I attempt to show that an argument berkeley uses in the 'dialogues' and 'principles' to support his contention that whatever is perceivable is perceived can be seen as an illuminating attempt to relate conceptualizing, Imaging and perceiving. In consequence it cannot be dismissed as resting on an elementary fallacy, But reflects on the conditions for the self ascription of experience.

I call the activity of assessing and developing improvements of our representational devices ‘conceptual engineering’.¹ The aim of this chapter is to present an argument for why conceptual engineering is important for all parts of philosophy (and, more generally, all inquiry). Section I of the chapter provides some background and defines key terms. Section II presents the argument. Section III responds to seven objections. The replies also serve to develop the argument and clarify what conceptual engineering is.

In this paper we examine Prior's reconstruction of Master Argument [4] in some modal-tense logic. This logic consists of a purely tense part and Diodorean definitions of modal alethic operators. Next we study this tense logic in the pure tense language. It is the logic $K_t 4$ plus a new axiom $:p \wedge Gp \supset PGp'$. This formula was used by Prior in his original analysis of Master Argument. is usually added as an extra axiom to (...) an axiomatization of the logic of linear time. In that case the set of moments is a total order and must be left-discrete without the least moment. However, the logic of Master Argument does not require linear time. We show what properties of the set of moments are exactly forced by in the reconstruction of Prior. We make also some philosophical remarks on the analyzed reconstruction. (shrink)