This book traces the development of formal logic from its origins inancient Greece to the present day. The authors first discuss the work oflogicians from Aristotle to Frege, showing how they were influenced by thephilosophical or mathematical ideas of their time. They then examinedevelopments in the present century.

This book argues against the view that mathematical knowledge is a priori,contending that mathematics is an empirical science and develops historically,just as ...

The object of this paper is to show why recent research in the psychology of deductive and probabilistic reasoning does not have.

The first systematic exposition of all the central topics in the philosophy of logic, Susan Haack's book has established an international reputation for its accessibility, clarity, conciseness, orderliness, and range as well as for its thorough scholarship and careful analyses. Haack discusses the scope and purpose of logic, validity, truth-functions, quantification and ontology, names, descriptions, truth, truth-bearers, the set-theoretical and semantic paradoxes, and modality. She also explores the motivations for a whole range of non-classical systems of logic, including many-valued logics, (...) fuzzy logic, moddal and tense logics, and relevance logics. Persupposing only an elementary knowledge of formal logic, this book includes many useful summary tables and diagrams, as well as a helpful glossary of technical terms. Wide-ranging, informative, and eminently readable, this book has proven a valuable resource for generations of students and scholars in a variety of disciplines outside philosophy needing guidance on the philosophy of logic. (shrink)

Humans and animals make inferences about the world under limited time and knowledge. In contrast, many models of rational inference treat the mind as a Laplacean Demon, equipped with unlimited time, knowledge, and computational might. Following H. Simon's notion of satisficing, the authors have proposed a family of algorithms based on a simple psychological mechanism: one-reason decision making. These fast and frugal algorithms violate fundamental tenets of classical rationality: They neither look up nor integrate all information. By computer simulation, the (...) authors held a competition between the satisficing "Take The Best" algorithm and various "rational" inference procedures. The Take The Best algorithm matched or outperformed all competitors in inferential speed and accuracy. This result is an existence proof that cognitive mechanisms capable of successful performance in the real world do not need to satisfy the classical norms of rational inference. (shrink)

Pollock describes an exciting theory of rationality and its partial implementation in OSCAR, a computer system whose descendants will literally be persons.

This book explores Hume's account of reason and its role in human understanding, seen in the context of other notable accounts by philosophers of the early modern period. David Owen offers new interpretations of many of Hume's most famous arguments about induction, belief, scepticism, the passions, and moral distinctions.

In this innovative study Patricia Kitcher argues that we can only understand the deduction of the categories in Kant's Critique of Pure Reason in terms of his attempt to fathom the psychological prerequisites of thought. Thus a consideration of his conception of psychology is essential to an understanding of his philosophy. Kitcher specifically considers Kant's claims about the unity of the thinking self; the spatial forms of human perceptions; the relations among mental states necessary for them to have content; the (...) relations between perceptions and judgment; and the limits of philosophical insight into psychological processes. (shrink)

The moral philosophy of the first half of the twentieth century, at least in the English-speaking part of the world, has been largely devoted to problems of an ontological or epistemological nature. This concentration of effort by many acute analytical minds has not produced any general agreement with respect to the solution of these problems; it seems likely, on the contrary, that the wealth of proposed solutions, each making some claim to plausibility, has resulted in greater disagreement than ever before, (...) and in some cases disagreement about issues so fundamental that certain schools of thought now find it unrewarding, if not impossible, to communicate with one another. Moral philosophers of almost all schools seem to agree, however, that no major possibility has been neglected during this period, and that every proposed solution which can be adjudged at all plausible has been examined with considerable thoroughness. It is now common practice, for example, for the authors of books on moral philosophy to introduce their own theories by what purports to be a classification and review of all \emph{possible} solutions to the basic problems of analysis; and in many cases, indeed, the primary defense of the author's own position seems to consist in the negative argument that his own position cannot fail to be correct because none of the others which he has mentioned is satisfactory. (shrink)

This is the first single-volume edition and translation of Frege's philosophical writings to include all of his seminal papers and substantial selections from all three of his major works.

Let me start with a well-known story. Kant held that logic and conceptual analysis alone cannot account for our knowledge of arithmetic: “however we might turn and twist our concepts, we could never, by the mere analysis of them, and without the aid of intuition, discover what is the sum [7+5]” (KrV, B16). Frege took himself to have shown that Kant was wrong about this. According to Frege’s logicist thesis, every arithmetical concept can be defined in purely logical terms, and (...) every theorem of arithmetic can be proved using only the basic laws of logic. Hence, Kant was wrong to think that our grasp of arithmetical concepts and our knowledge of arithmetical truth depend on an extralogical source—the pure intuition of time (Frege 1884, §89, §109). Arithmetic, properly understood, is just a part of logic. (shrink)

First published in 1995. Routledge is an imprint of Taylor & Francis, an informa company.

Can the output of human cognition be predicted from the assumption that it is an optimal response to the information-processing demands of the environment? A methodology called rational analysis is described for deriving predictions about cognitive phenomena using optimization assumptions. The predictions flow from the statistical structure of the environment and not the assumed structure of the mind. Bayesian inference is used, assuming that people start with a weak prior model of the world which they integrate with experience to develop (...) stronger models of specific aspects of the world. Cognitive performance maximizes the difference between the expected gain and cost of mental effort. Memory performance can be predicted on the assumption that retrieval seeks a maximal trade-off between the probability of finding the relevant memories and the effort required to do so; in categorization performance there is a similar trade-off between accuracy in predicting object features and the cost of hypothesis formation; in casual inference the trade-off is between accuracy in predicting future events and the cost of hypothesis formation; and in problem solving it is between the probability of achieving goals and the cost of both external and mental problem-solving search. The implemention of these rational prescriptions in neurally plausible architecture is also discussed. (shrink)

In Rationality and Logic, Robert Hanna argues that logic is intrinsically psychological and that human psychology is intrinsically logical. He claims that logic is cognitively constructed by rational animals and that rational animals are essentially logical animals. In order to do so, he defends the broadly Kantian thesis that all rational animals possess an innate cognitive "logic faculty." Hanna 's claims challenge the conventional philosophical wisdom that sees logic as a fully formal or "topic-neutral" science irreconcilably separate from the species- (...) or individual-specific focus of empirical psychology.Logic and psychology went their separate ways after attacks by Frege and Husserl on logical psychologism--the explanatory reduction of logic to empirical psychology. Hanna argues, however, that--despite the fact that logical psychologism is false--there is an essential link between logic and psychology. Rational human animals constitute the basic class of cognizers or thinkers studied by cognitive psychology; given the connection between rationality and logic that Hanna claims, it follows that the nature of logic is significantly revealed to us by cognitive psychology. Hanna 's proposed "logical cognitivism" has two important consequences: the recognition by logically oriented philosophers that psychologists are their colleagues in the metadiscipline of cognitive science; and radical changes in cognitive science itself. Cognitive science, Hanna argues, is not at bottom a natural science; it is both an objective or truth-oriented science and a normative human science, as is logic itself. (shrink)

This book presents a remarkable diversity of contemporary opinions on the prospects of addressing philosophical topics from a psychological perspective. It considers the history and philosophical merits of psychologism, and looks systematically at psychologism in phenomenology, cognitive science, epistemology, logic, philosophy of language, philosophical semantics, and artificial intelligence.

Default reasoning occurs whenever the truth of the evidence available to the reasoner does not guarantee the truth of the conclusion being drawn. Despite this, one is entitled to draw the conclusion “by default” on the grounds that we have no information which would make us doubt that the inference should be drawn. It is the type of conclusion we draw in the ordinary world and ordinary situations in which we find ourselves. Formally speaking, ‘nonmonotonic reasoning’ refers to argumentation in (...) which one uses certain information to reach a conclusion, but where it is possible that adding some further information to those very same premises could make one want to retract the original conclusion. It is easily seen that the informal notion of default reasoning manifests a type of nonmonotonic reasoning. Generally speaking, default statements are said to be true about the class of objects they describe, despite the acknowledged existence of “exceptional instances” of the class. In the absence of explicit information that an object is one of the exceptions we are enjoined to apply the default statement to the object. But further information may later tell us that the object is in fact one of the exceptions. So this is one of the points where nonmonotonicity resides in default reasoning. (shrink)

This paper considers the question of whether Mill's account of the nature and justificatory foundations of deductive logic is psychologistic. Logical psychologism asserts the dependency of logic on psychology. Frequently, this dependency arises as a result of a metaphysical thesis asserting the psychological nature of the subject matter of logic. A study of Mill's System of Logic and his Examination reveals that Mill held an equivocal view of the subject matter of logic, sometimes treating it as a set of psychological (...) processes and at other times as the objects of those processes. The consequences of each of these views upon the justificatory foundations of logic are explored. The paper concludes that, despite his providing logic with a prescriptive function, and despite his avoidance of conceptualism, Mill's theory fails to provide deductive logic with a justificatory foundation that is independent of psychology. (shrink)

This is a position paper concerning the role of empirical studies of human default reasoning in the formalization of AI theories of default reasoning. We note that AI motivates its theoretical enterprise by reference to human skill at default reasoning, but that the actual research does not make any use of this sort of information and instead relies on intuitions of individual investigators. We discuss two reasons theorists might not consider human performance relevant to formalizing default reasoning: (a) that intuitions (...) are sufficient to describe a model, and (b) that human performance in this arena is irrelevant to a competence model of the phenomenon. We provide arguments against both these reasons. We then bring forward three further considerations against the use of intuitions in this arena: (a) it leads to an unawareness of predicate ambiguity, (b) it presumes an understanding of ordinary language statements of typicality, and (c) it is similar to discredited views in other fields. We advocate empirical investigation of the range of human phenomena that intuitively embody default reasoning. Gathering such information would provide data with which to generate formal default theories and against which to test the claims of proposed theories. Our position is that such data are the very phenomena that default theories are supposed to explain. (shrink)

This paper argues that Frege's notoriously long commitment to Kant's thesis that Euclidean geometry is synthetic _a priori_ is best explained by realizing that Frege uses ‘intuition’ in two senses. Frege sometimes adopts the usage presented in Hermann Helmholtz's sign theory of perception. However, when using ‘intuition’ to denote the source of geometric knowledge, he is appealing to Hermann Cohen's use of Kantian terminology. We will see that Cohen reinterpreted Kantian notions, stripping them of any psychological connotation. Cohen's defense of (...) his modified Kantian thesis on the unique status of the Euclidean axioms presents Frege's own views in a much more favorable light. (shrink)

Husserl and Frege did not criticize psychologism on the ground that it deduced the norms of logic from non-normative premises (naturalistic fallacy), as is often supposed. Rather, their refutation of psychologism assumes that such a deduction is possible. Husserl compared the rules of logic to those of technology, on the supposition that they have a purely theoretical basis. This conception of logic is critically examined, and it is argued (contra Follesdal) that Frege held a similar view.

Grundriss der Geschichte der Philosophie ist ein unveränderter, hochwertiger Nachdruck der Originalausgabe aus dem Jahr 1866. Hansebooks ist Herausgeber von Literatur zu unterschiedlichen Themengebieten wie Forschung und Wissenschaft, Reisen und Expeditionen, Kochen und Ernährung, Medizin und weiteren Genres. Der Schwerpunkt des Verlages liegt auf dem Erhalt historischer Literatur. Viele Werke historischer Schriftsteller und Wissenschaftler sind heute nur noch als Antiquitäten erhältlich. Hansebooks verlegt diese Bücher neu und trägt damit zum Erhalt selten gewordener Literatur und historischem Wissen auch für die Zukunft (...) bei. (shrink)

The modem rationalist tradition initiated by Descartes has as one of its central tenets the independence of the human understanding from the senses. Regardless of the different ways in which independence from experience is understood, there is much common ground among the modem views on the a priori. Yet Kant, culminating this tradition, introduces an entirely new conception of the a priori never before articulated in the history of philosophy. This is the notion of elements in knowledge which are independent (...) of experience but nevertheless closely connected, in a special way, with experience.Although for Kant the a priori has a privileged position in the structure of knowledge - as it has for other modem rationalist philosophers - one of the most striking, and often neglected, aspect of his conception of the a priori is the great extent to which it is opposed to foundationalism. (shrink)

Psychologism is the target of vehement disapproval in much of mainstream philosophy from Kant to the present day. Yet although antipsychologistic rhetoric is adamant, there is little substantive argument against psychologism to be discovered in contemporary discussions of the problem. Many recent influential philosophical projects, moreover, including intuitionistic logic, conceptualism in the ontology of mathematics and the program to naturalize epistemology, are in different ways efforts to apply modern psychology in the service of philosophical theory. In this essay, I critically (...) survey the history of attacks on psychologism and conclude with a refutation of eight of the most important objections of the theory. My purpose is both to try to clarify the concept of psychologism and to encourage a renewed dialectical interaction between proponents and opponents of the philosophical merits of psychologism. (shrink)

This paper presents a position called Scheme-based Alethic Realism, which reconciles a realist position on the nature of truth with a pluralistic Kantian perspective that allows for multiple environments in which truthmaking relationships are established. We argue that truthmaking functions are constrained by a stable phenomenal world and a stable cognitive architecture. This account takes truth as normatively distinct from epistemic justification while relativizing the truth conditions of our statements to what we call Frameworks. The pluralistic aspect allows that these (...) stable elements, while constraining representational and linguistic schemes, do not define a single framework for truthmaking relations. We strengthen this position by considering themes on situated rational agency from cognitive science and artificial intelligence, arguing that whatever enables or supports rational action within a particular environment must figure into some account of truth and truthmaking, and vice versa. (shrink)