A selection function based semantics is offered for the 'can' of ability based on the idea that 'John can run a four minute mile' is true iff John would do so under the right conditions, meaning that he would do so under at least one appropriately chosen test condition. Completeness is proved for an axiom system and semantics based on this idea, and the logic turns out to be interestingly different from any standard system of modal logic.

In a 1994 ANALYSIS article Peter Klein and Ted Warfield show that an epistemically more coherent set of beliefs often has a smaller unconditional probability of joint truth than some of its less coherent subsets. They conclude that epistemic justification, as understood in one version of a coherence theory of justification, is not truth conducive. After getting clear about what truth conduciveness requires, I show that their argument does not tell against BonJour's coherence theory.

In this essay I present a new version of the Paradox of the Knower and show that this new paradox vitiates a certain argument against epistemic closure. I then prove a theorem that relates the new paradox to epistemological scepticism. I conclude by assessing the use of the Knower in arguments against syntactical treatments of knowledge.

In this essay I renew the case for Conditional Excluded Middle in light of recent developments in the semantics of the subjunctive conditional. I argue that Michael Tooley's recent backward causation counterexample to the Stalnaker-Lewis comparative world similarity semantics undermines the strongest argument against CXM, and I offer a new, principled argument for the validity of CXM that is in no way undermined by Tooley's counterexample. Finally, I formulate a simple semantics for the subjunctive conditional that is consistent with both (...) CXM and Tooley's counterexample. (shrink)

In The Scientific Image B. C. van Fraassen argues that a theory of explanation ought to take the form of a theory of why-questions, and a theory of this form is what he provides. Van Fraassen's account of explanation is good, as far as it goes. In particular, van Fraassen's theory of why-questions adds considerable illumination to the problem of alternative explanations in psychodynamics. But van Fraassen's theory is incomplete because it ignores those classes of explanations that are answers not (...) to why-questions but to how-questions. In this article I provide a unified theory of explanatory questions that comprehends both how-questions and why-questions, and I show that a question-theoretic approach to explanation can be defended independently of van Fraassen's programme of Constructive Empiricism. (shrink)

[IMPORTANT CORRECTION - See end of abstract.] In Syntactical Treatments of Modality, with Corollaries on Reflexion Principles and Finite Axiomatizability, Acta Philosophica Fennica 16 (1963), 153–167, Richard Montague shows that the use of a single syntactic predicate (with a context-independent semantic value) to represent modalities of alethic necessity and idealized knowledge leads to inconsistency. In A Note on Syntactical Treatments of Modality, Synthese 44 (1980), 391–395, Richmond Thomason obtains a similar impossibility result for idealized belief: under a syntactical treatment of (...) belief, the assumption that idealized belief is deductively closed, together with certain other plausible conditions on idealized belief, imply that an ideal believer with consistent beliefs cannot believe the truth of Robinson's Arithmetic. In this essay I assert an impossibility result similar to Thomason's but which does not assume that belief is deductively closed or ideal in any other way. There are technical mistakes in the formulations of Lemmas 1-4 and Theorem 2, however. Corrections can be found in the Erratum section of the author's website. (shrink)

In “Backward Causation and the Stalnaker–Lewis Approach to Counterfactuals,” Analysis 62:191–7, (2002), Michael Tooley argues that if a certain kind of backward causation is possible, then a Stalnaker–Lewis comparative world similarity account of the truth conditions of counterfactuals cannot be sound. In “Tooley on Backward Causation,” Analysis 63:157–62, (2003), Paul Noordhof argues that Tooley’s example can be reconciled with a Stalnaker–Lewis account of counterfactuals if the comparative world similarity relation on which the Stalnaker–Lewis account relies is allowed to be antecedent-relative. (...) In this paper I show that taking comparative world similarity to be antecedent-relative results in a formal semantics which is a comparative world similarity semantics in name only. (shrink)

In ‘Syntactical Treatments of Modality, with Corollaries on Reflexion Principles and Finite Axiomatizability’, Acta Philosophica Fennica16 (1963), 153–167, Richard Montague shows that the use of a single syntactic predicate (with a context-independent semantic value) to represent modalities of alethic necessity and idealized knowledge leads to inconsistency. In ‘A Note on Syntactical Treatments of Modality’, Synthese44 (1980), 391–395, Richmond Thomason obtains a similar impossibility result for idealized belief: under a syntactical treatment of belief, the assumption that idealized belief is deductively closed, (...) together with certain other plausible conditions on idealized belief, imply that an ideal believer with consistent beliefs cannot believe the truth of Robinson's Arithmetic. In this essay I show that an impossibility result similar to Thomason's can be obtained which does not assume that belief is deductively closed or ideal in any other way. (shrink)

In this essay I renew the case for Conditional Excluded Middle (CXM) in light of recent developments in the semantics of the subjunctive conditional. I argue that Michael Tooley’s recent backward causation counterexample to the Stalnaker-Lewis comparative world similarity semantics undermines the strongest argument against CXM, and I offer a new, principled argument for the validity of CXM that is in no way undermined by Tooley’s counterexample. Finally, I formulate a simple semantics for the subjunctive conditional that is consistent with (...) both CXM and Tooley’s counterexample. (shrink)

In “The Paradox of the Knower without Epistemic Closure”, MIND 110:319-33, 2001, I develop a version of the Knower Paradox which does not assume epistemic closure, and I use it to argue that the original Knower Paradox does not support an argument against epistemic closure. In “The Paradox of the Knower without Epistemic Closure?”, MIND 113:95-107, 2004, Gabriel Uzquiano, using his own result, argues that my rebuttal to the anti-closure argument is not successful. I respond here by arguing that in (...) order to use Uzquiano’s result in an argument against closure, one must assume an implausible skepticism about arithmetic. (shrink)

I give a critique of the argument against the Identity of Indiscernibles found in Max Black's dialogue "The Identity of Indiscernibles". I begin by postulating and giving existence and individuation conditions for actually existent thought experiment characters on analogy with fictional characters as postulated in Peter van Inwagen's "Creatures of Fiction". I then show that Black's two-spheres thought experiment raises not one but two discernibility questions: 1) Is it true in the two-spheres thought experiment that there exist two indiscernible spheres? (...) NO. 2) Is it true in the actual world that there are two indiscernible sphere-characters? YES. (shrink)

This book offers both the theoretical background behind the minority effect, teachers' personal experiences as they experienced being a minority, and their analyses and insights for teaching diverse learners. This book uses real-life experiences of diverse people to illustrate that, if not understood and addressed, situational minorities at school or work are unlikely to perform at their highest potentials.

Despite the results of David Lewis, Peter Gärdenfors, and others, showing that imaging and classical conditionalization coincide only in the most trivial probabilistic models of belief revision, it turns out that imaging on a proposition A can always be described via Popper function conditionalization on a proposition that entails A. This result generalizes to any method of belief revision meeting certain minimal requirements. The proof is illustrated by an application of imaging in the context of the Monty Hall Problem.

I show that given Jonathan Bennett's theory of 'even if,' the following statement is logically true iff the principle of conditional excluded is valid: (SE) If Q and if P wouldn't rule out Q, then Q even if P. Hence whatever intuitions support the validity of (SE) support the validity of Conditional Excluded Middle, too. Finally I show that Bennett's objection to John Bigelow's theory of the conditional can be turned into a (perhaps) more telling one, viz. that on Bigelow's (...) theory 'if P then Q' and 'if P and Q then R' do not jointly entail 'if P then R'. (shrink)

In A World of States of Affairs(Cambridge University Press, 1997) David Armstrong offers acomprehensive metaphysics based on the thesis that the world consistsof states of affairs. Among the entities postulated by Armstrong's theory are relations, including non-symmetrical relations, and whileArmstrong does not agree with Russell that all relations have adirection or definite order among their places, he does explicitlyacknowledge that the slots of a non-symmetrical relation have adefinite order or direction. I first show that non-symmetricalrelations pose a problem for Armstrong's (...) theory by raising TheProblem of Converse Relations. I then argue that the bestresolution of this problem in the context of Armstrong's theoryinvolves adopting an analysis of the order or direction of a relationthat differs from the analysis that Russell assumes. I conclude bydiscussing a further problem facing Armstrong's ontology: TheProblem of Converse Relational Properties. (shrink)

Stephen Barker argues that a possible worlds semantics for the counterfactual conditional of the sort proposed by Stalnaker and Lewis cannot accommodate certain examples in which determinism is true and a counterfactual Q > R is false, but where, for some P, the compound counterfactual P > (Q > R) is true. I argue that the completeness theorem for Lewis’s system VC of counterfactual logic shows that Stalnaker–Lewis semantics does accommodate Barker’s example, and I argue that its doing so should (...) be understood as showing that the example is an exception to Lewis’s Time’s Arrow requirements. (shrink)

In "Backward causation and the Stalnaker-Lewis approach to counterfactuals," Analysis 62 (2002): 191–97, Michael Tooley argues that if a certain kind of backward causation is possible, then a Stalnaker-Lewis style comparative world similarity account of the truth conditions of counterfactuals cannot be sound. Tooley’s target is one particular type of semantics, but, as I show, the significance of Tooley’s example goes well beyond its consequences for any one semantics for the conditional.

In "Against the Indicative," AUSTRALASIAN JOURNAL OF PHILOSOPHY 72 (1994): 17-26, and more recently in "Classifying `Conditionals': the Traditional Way is Wrong", ANALYSIS 60 (2000): 147, V.H. Dudman argues that (a) `If Oswald didn't shoot Kennedy then someone else did' and (b) `If Oswald doesn't shoot Kennedy then someone else will' should not be classified together as "indicative conditionals." Dudman relies on the assumption that (a) is entailed by (c) `Someone shot Kennedy', whereas (b) is not entailed by (d) `Someone (...) will shoot Kennedy'. I argue that the same reasoning which shows that (d) does not entail (b) also shows that (c) does not entail (a). One upshot is that Dudman's and Mellor's respective interpretations of so-called past indicative conditionals cannot be correct. (shrink)

Nonmonotonic consequence is the subject of a vast literature, but the idea of a nonmonotonic counterpart of logical inconsistency—the idea of a defeasible property representing internal conflict of an inductive or evidential nature—has been entirely neglected. After considering and dismissing two possible analyses relating nonmonotonic consequence and a nonmonotonic counterpart of logical inconsistency, this paper offers a set of postulates for nonmonotonic inconsistency, an analysis of nonmonotonic inconsistency in terms of nonmonotonic consequence, and a series of results showing that nonmonotonic (...) inconsistency conforms to these postulates given the analysis of nonmonotonic inconsistency presented here and certain postulates for nonmonotonic consequence. The results presented here establish the interest of certain previously undiscussed postulates of nonmonotonic consequence. These results also show that nonmonotonicity, which has never seemed useful in the formulation of general principles governing nonmonotonic reasoning, is relevant to the positive characterization of nonmonotonic inference after all. (shrink)

Discrepancies between an agent's goals and beliefs play an important, if implicit, role in determining what a rational agent is motivated to do. This is most obvious in cases where an agent achieves a complex goal incrementally and must deliberate anew as each milestone is reached. In such cases the concept of goal/belief discrepancy defines an appropriate space to which a degree-of-achievement yardstick can be applied. This paper presents soundness and completeness results concerning a logic for reasoning about goal/belief discrepancy, (...) and it is suggested that a certain species of goal/belief discrepancy captures the concept of desire. (shrink)

Temporal necessity and the subjunctive conditional appear to be related by the principle of Past Predominance, according to which past similarities and differences take priority over future similarities and differences in determining the comparative similarity of alternative possible histories with respect to the present moment. R. H. Thomason and Anil Gupta have formalized Past Predominance in a semantics that combines selection functions with branching time; in this paper I show that Past Predominance can be formalized and axiomatized using ordinary possible (...) worlds semantics (without branching time). (shrink)

In his well-known 1952 dialogue Max Black describes a counterexample to the Principle of the Identity of Indiscernibles (PII). The counterexample is a world containing nothing but two purportedly indiscernible iron spheres. Reflecting on Black's example, Robert Adams uses the possibility of a world containing two almost indiscernible spheres to argue for the possibility of the indiscernible spheres world. One of Adams's almost indiscernible spheres has a small impurity, and, Adams writes, "Surely... the absence of the impurity would not make (...) such a universe impossible." The appeal to "surely" constitutes a gap in Adams's argument. This paper bridges the gap with a premise that exploits the counterfactual conditional and the related notion of causal independence. The paper then argues that causal independence bears in a similar way on an issue Nathan Salmon raises concerning Kripke's argument for the Essentiality of Origins. (shrink)

In ‘Two Spheres, Twenty Spheres, and the Identity of Indiscernibles,’ Della Rocca argues that any counterexample to the PII would involve ‘a brute fact of non-identity [. . .] not grounded in any qualitative difference.’ I respond that Adams's so-called Continuity Argument against the PII does not postulate qualitatively inexplicable brute facts of identity or non-identity if understood in the context of Kripkean modality. One upshot is that if the PII is understood to quantify over modal as well as non-modal (...) properties, the qualitative explicability of numerical distinctness requires not the PII but a principle of the identity of necessary indiscernibles. (shrink)

This note corrects an error in the statement and proof of Propositions 9 and 10 of [C. Cross, Nonmonotonic inconsistency, Artificial Intelligence 149 (2) (2003) 161–178]. Both results turn out to depend on the postulate of Consistency Preservation.

I show the incompatibility of two theses: (a) to desire the truth of p amounts to believing a certain proposition about the value of p’s truth; (b) one cannot be said to desire the truth of p if one believes that p is true. Thesis (a), the Desire-As-Belief Thesis, has received much attention since the late 1980s. Thesis (b) is an epistemic variant of Socrates’ remark in the Symposium that one cannot desire what one already has. It turns out that (...) (a) and (b) cannot both be true if it is possible for there to exist an agent who has a desire initially, say the desire for the truth of p, and then expands the corpus of propositions she believes to include p. This result provides a new route to the denial of (a). (shrink)

I present and discuss two logical results. The first shows that a non-trivial counterfactual analysis exists for any contingent proposition that is false in at least two possible worlds. The second result identifies a set of conditions that are individually necessary and jointly sufficient for the success of a counterfactual analysis. I use these results to shed light on the question whether disposition ascribing propositions can be analyzed as Stalnaker-Lewis conditional propositions. The answer is that they can, but, in order (...) for a counterfactual analysis to work, the antecedent and consequent must be related in a particular way, and David Lewis’s Time’s Arrow constraints on comparative world similarity must be relaxed. The upshot is that counterfactual analyses are easy to come by, in principle, even if not in practice. In that sense, it’s easy to be iffy. (shrink)

Dretske's conclusive reasons account of knowledge is designed to explain how epistemic closure can fail when the evidence for a belief does not transmit to some of that belief's logical consequences. Critics of Dretske dispute the argument against closure while joining Dretske in writing off transmission. This paper shows that, in the most widely accepted system for counterfactual logic , conclusive reasons are governed by an informative, non-trivial, logical transmission principle. If r is a conclusive reason for believing p in (...) Dretske's sense, and if p logically implies q, and if p and q satisfy one additional condition, it follows that r is a conclusive reason for believing q. After introducing this additional condition, I explain its intuitive import and use the condition to shed new light on Dretske's response to scepticism, as well as on his distinction between the so-called ‘lightweight’ and ‘heavyweight’ implications of a piece of perceptual knowledge. (shrink)

Peter Gärdenfors has proved (Philosophical Review, 1986) that the Ramsey rule and the methodologically conservative Preservation principle are incompatible given innocuous-looking background assumptions about belief revision. Gärdenfors gives up the Ramsey rule; I argue for preserving the Ramsey rule and interpret Gärdenfors's theorem as showing that no rational belief-reviser can avoid reasoning nonmonotonically. I argue against the Preservation principle and show that counterexamples to it always involve nonmonotonic reasoning. I then construct a new formal model of belief revision that does (...) accommodate nonmonotonic reasoning. (shrink)

I compare the failure of counterfactual dependence as a criterion of event causation to the failure of stochastic dependence as a criterion of causal law. Counterexamples to the stochastic analysis arise from cases of Simpson's Paradox, and Nancy Cartwright has suggested a way of transforming the stochastic analysis into something that avoids these counterexample. There is an analogical relationship between cases of Simpson's Paradox and cases of causal overdetermination. I exploit this analogical relationship to motivate my own view about the (...) connection between counterfactuals and event causation. According to my view, counterfactuals and event causation are intimately connected by a principle which falls short of being an analysis but which, as I show, correctly handles not only overdetermination but common causes as well. (shrink)

I give a probabilistic semantics for modal logic in which modal operators function as quantifiers over Popper functions in probabilistic model sets, thereby generalizing Kripke's semantics for modal logic.

The coherence of the whole truth is a presupposition of any holistic coherence theory of justification that postulates a positive connection between justification and truth, for unless the whole truth is itself systemically coherent there is no reason to look for systemic coherence when deciding whether one is justified in accepting a given body of beliefs as true. This paper develops a formal model of holistic evidential coherence and uses this model to formalize and defend the claim that the whole (...) truth must be coherent in an evidential sense. (shrink)

I investigate the consequences of interpreting Lehrer's account of system-relative justification as a theory of inductive inference. I discuss which assumptions about coherence would be sufficient to make the account of inductive inference derived from Lehrer's theory conform to a series of widely discussed general principles, including those constitutive of cumulative reasoning. I then discuss the epistemological significance of the resulting theory of inductive inference.

This is a review of Jean Curthoys and Victor H. Dudman, VICTOR DUDMAN'S GRAMMAR AND SEMANTICS (Hampshire, UK: Palgrave Macmillan, 2012).

This is a review of Moritz Schulz, COUNTERFACTUALS AND PROBABIITY (Oxford: Oxford University Press, 2017).

This is a review of CONDITIONALS: FROM PHILOSOPHY TO COMPUTER SCIENCE, edited by Crocco G., del Cerro L. Fariñas, and Herzig A., Studies in logic and computation, no. 5, Clarendon Press, Oxford University Press, Oxford and New York 1995.

Educational institutions all over the world continue to attract the services of foreign-born scholars. In addition to the culture shock that immigrants experience in unfamiliar countries, these scholars often undergo "pedagogical shock." Through autobiographical accounts of foreign-born professors from Africa, Asia, Europe, and the US, this volume examines the experiences of foreign-born professors around the world to provide insight on the curricular, school-systemic, and sociological differences and challenges that are encountered, and how to help resolve them. It will help administrators, (...) institutions, and immigration and comparative education scholars understand the cross-cultural challenges and coping strategies that define the private and professional lives of foreign-born professors across the globe. (shrink)

Paul uses a rich variety of metaphors to express the significance of Jesus' death. Far from giving permission to those in power to silence the powerless, the cross becomes the paradigm of self-sacrificing service for the whole community of faith.

First published in the most ambitious international philosophy project for a generation; the _Routledge Encyclopedia of Philosophy_. _Logic from A to Z_ is a unique glossary of terms used in formal logic and the philosophy of mathematics. Over 500 entries include key terms found in the study of: * Logic: Argument, Turing Machine, Variable * Set and model theory: Isomorphism, Function * Computability theory: Algorithm, Turing Machine * Plus a table of logical symbols. Extensively cross-referenced to help comprehension and (...) add detail, _Logic from A to Z_ provides an indispensable reference source for students of all branches of logic. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Buddhist-Christian Studies 24.1 (2004) 117-133 [Access article in PDF] Emptiness, Kenōsis, History, and Dialogue: The Christian Response to Masao Abe's Notion of "Dynamic Śūnyatā " in the Early Years of the Abe-Cobb Buddhist-Christian Dialogue Charles B. Jones The Catholic University of America Introduction Between 1980 and 1993, the Japanese Zen scholar Masao Abe resided in the United States, teaching in various places.1 This brought him into contact with (...) many American scholars and theologians, among whom was John Cobb, a Protestant theologian then working in the area of process theology. Many of the ideas that Abe brought from Japanese Buddhism and particularly from the "Kyōtō School" of Japanese philosophy appeared to Cobb intriguingly congruent with his theological work, and the two began a series of dialogues that came to include a larger and larger circle of Christian theologians2 and (mostly Western) Buddhist scholar-practitioners. The end result was a series of informal encounters as well as a series of three formal "International Buddhist-Christian Conferences" (1980, 1984, 1987; a second series of dialogues were held without Abe's attendance starting in 1998 after a hiatus under the name "International Buddhist-Christian Theological Encounter"3 ). From these encounters came an impressive number of publications from Abe and from a variety of other participants in what is sometimes known as the "Abe-Cobb Encounter."The agenda, following Cobb's suggestion and vocabulary, was to allow each side to "cross over" into the other; in other words, to study and internalize the worldview of the other in as much depth as possible without converting or losing one's connection with one's home tradition, abiding in the other side as a guest. Later, one was to "cross back," come home to one's own tradition and reflect on the benefits gained in wearing the other's shoes for a time.4 This agenda, which emphasized understanding the other's worldview and concepts of ultimate reality, suited the highly intellectual style of the dialogues, focused as they were on philosophical and theological concerns. [End Page 117]Nevertheless, even given the concern to study and understand the other's philosophical standpoint, a curious disconnect emerges when one studies the literature produced in this dialogue. During the early phase of these encounters in the 1980s, each side, Buddhist and Christian, appears to have taken one text as normative for the entirety of the other's tradition. For Abe, following his predecessors in the KyōtōSchool, the emblematic textfor Christianity was avery short one: the hymn toChrist recorded by Paul in Philippians 2:6-11. He was particularly drawn to the concept of kenōsis, "emptying," which he thought might serve as a cognate for the Buddhist idea of "emptiness" (Skt: śūnyatā ). While the Christians participating in the dialogueaccepted this as a point of contact, albeit with some reservations, others have objected strenuously to this approach, saying that Abe's method of interpreting this text did not hold to responsible methods of exegesis, and at any rate the passage was much too minute to support an entire theology of God and creation.5The Christian side by and large adopted much the same strategy in coming to grips with Buddhist thought, choosing a brief text as the paradigmatic statement of the Buddhist view of ultimate reality: the Mūlamadhyamaka-kārikā (Root Stanzas on the Middle Way; hereafter the MMK) of the second-century Buddhist thinker Nāgārjuna. In this instance, objections from the Buddhist side were not forthcoming, because Abe himself took the MMK as a normative statement of Buddhist thought. Nevertheless, his own presentation of Buddhism, especially his key notion of "dynamic śūnyatā, " went considerably beyond Nāgārjuna's presentation and thus elicited some objections from the Christian side for not hewing to their own understanding of Nāgārjuna. Because Abe never responded to these objections directly, the misunderstanding was left unresolved... (shrink)

This is a new release of the original 1925 edition.

Introduction: the ways and means of cultural change -- Science, industry and the invention of a new worldview -- Management as cultural authority -- The cultural values of work and leisure -- The strategy & spirit of capitalism -- From material need to consumer culture -- Higher learning as marketplace -- Globalization of the tightening systems knot -- Time to think -- Balancing values through cultural change -- Progress and myth -- Knowledge devalued: summary & conclusions.

Bulang He,1,2 Jeffrey M Hamdorf2 1Liver and Kidney Transplant Unit, Sir Charles Gairdner Hospital, Perth, WA, Australia; 2School of Surgery, The University of Western Australia, Perth, WA, Australia Aims: The aim of this paper was to review the current status of laparoscopic/robotic kidney transplant and evaluate its feasibility and safety in comparison with conventional standard "open" kidney transplant. Methods: An electronic search of PubMed, Embase, and the Cochrane library database was performed to identify the papers between January 1980 and (...) June 2013 that reported on laparoscopic/robotic kidney transplantation. The terms "laparoscopic kidney/renal transplant" and "robotic kidney/renal transplant " were used. Cross-referencing was also used to find the further publications. Only English language reports were selected and accepted for descriptive analysis. Results: A total of 17 papers and abstracts were retrieved. There were two case-control studies of small volume. High-level evidence comparing the safety and efficacy of laparoscopic/robotic kidney transplant with conventional open kidney transplant was not available at the time of this review. Conclusion: The limited published data have suggested that laparoscopic/robotic kidney transplant may offer the advantages of less pain, better cosmesis, possible shorter hospital stay, and fewer wound complications, without compromising graft function. Accordingly, some immunosuppressive agents, such as sirolimus, might be able to be commenced earlier, after laparoscopic/robotic kidney transplant. The techniques are various at this early stage. A uniformed operative technique may be established in the near future. With refinement of laparoscopic devices, this technique may be widely employed. Further studies will be needed to demonstrate the advantages of laparoscopic/robotic kidney transplant over the conventional open kidney transplant. Keywords: laparoscopic surgery, robotic surgery. (shrink)

"....an admirably clear account of Heidegger's relation to the philosophical tradition, and especially of his criticism of Cartesianism." -- Richard Rorty, University of Virginia.

This volume brings together for the first time some of the most helpful and insightful essays on the four most influential and discussed philosophers in the history of existentialism: Kierkegaard, Nietzsche, Heidegger, and Sartre.

As originally planned this volume was meant to cover a somewhat wider scope than, in fact, it has turned out to do. When, in rg68, I initially conceived of preparing it, it was proposed to deal with several aspects of early modern scepticism, in addition to the fortuna of the Academica, and to publish various loosely related pieces under the title of 'Studies in the History of Early Modern Scepticism. ' Thereby, I foresaw that I would exhaust my knowledge of (...) the subject and would then be able to turn my attention to other matters. In initiating my research on this topic, however, I soon found that there remained a much greater bulk of material to study than could possibly be dealt with between the covers of the single modest volume which I envisioned. My proposed section on Cicero's Academica was to cover between 50 and 75 pages in the original plan. It soon became apparent, however, especially after Joannes Rosa's hitherto unstudied commentary on Cicero's work was uncovered, that this material would have to be treated at a much greater length than I had foreseen. The present volume is the result of this expanded investigation. The monograph which has come from this alteration in plans has, I think, the virtues of continuity and cohesive ness and one hopes that these advantages offset the benefits of a broader scope which were sacrificed. (shrink)