The central and probably most controversial point concerning the psychologism — anti-psychologism debate is the problem of Frege’s alleged influence on the change in Husserl’s views. Contemporary thinkers investigating the early period of Husserl’s philosophy have attempted to show that the opinion that Frege’s doctrine had a traumatic influence on Husserl’s views is not justified. This paper, which tries to maintain a balance between strictly philosophical argumentation and narrowly understood historical argumentation, suggests an alternative solution. By appealing to (...) Frege’s works published before 1894, the locus of psychologism will be determined. Afterwards, I will present Husserl’s and Frege’s views on the elucidation procedure and the distinction between calculus and ‘lingua characteristica’. By discussing Husserl’s works from 1894-1897, I will show that his standpoint changed dramatically as he entered into the anti-psychological program, involving a new theory of concepts, judgment, and the so-called ‘pure Fregean flavour’ — a new account of logical content. (shrink)

In this paper, I argue that social psychologism is the most philosophically appealing form of psychologism. I present two arguments in support of social psychologism. The first is that this form of psychologism allows philosophers to justify normative claims about human reasoning. In the second part of this paper I argue that social psychologism ameliorates historical concerns with psychologism in general. The conclusion I draw from this discussion is that a need to outline and (...) justify a normative system for deductive reasoning requires some discussion of how formal systems and human minds connect to one another. (shrink)

According to Edmund Husserl in the Prolegomena to Pure Logic, which constitutes the preliminary rational foundation for – and also the entire first volume of – his Logical Investigations, pure logic is the a priori theoretical, nomological science of „demonstration“.1 For him, demonstration includes both consequence and provability. Consequence is the defining property of all and only formally valid arguments, i. e., arguments that cannot lead from true premises to false conclusions. And provability is the property of a (...) class='Hi'>logical system such that, for every truth of logic in that system, there is, at least in principle, a rigorous step-by-step logically valid procedure demonstrating its validity according to strictly universal, ideal, and necessary logical laws. In this way, the laws of pure logic completely determine its internal structure. Moreover, these laws and these proofs are all knowable a priori, with selfevident insight. So not only is pure logic independent of any other theoretical science, in that it requires no other science in order to ground its core notion of demonstration, it also provides both epistemic and semantic foundations for every other theoretical science, as well as every practical discipline or „technology. “ To the extent that pure logic is the foundation of every other. (shrink)

Logical psychologism is the position that logic is a special branch of psychology, that logical laws are descriptíons of experience to be arrived at through observation, and are a posteriori.The accepted arguments against logical psychologism are effective only when directed against this extreme version. However, the clauses in the above characterization are independent and ambiguous, and may be considered separately. This separation permits a reconsideration of less extreme attempts to tie logic to psychology, such as (...) those defended by Mill and Boole. It also provides the basis for a reexamination of the relationship between logic and psychology, and raises the possibility of a deeper investigation into the nature of logic itself. (shrink)

I propose in this text that Husserl’s response to his contemporaries, critics and immediate predecessors in Logical Investigations consists in the development of circular strategy. Husserl does not challenge psychologsim, empiricism or neo-Kantianism by immediately assuming a position of epistemological primacy over these philosophies. To the contrary, Husserl philosophically challenges these positions by enacting a circularity that already underlies them. Husserl’s critical distance from these theories implies a methodological proximity which enables him to advance his phenomenological project with constant (...) backward reference to the theories he challenges. Husserl’s circular philosophy transforms the themes it investigates and the theories it criticizes, transforming itself in that process. (shrink)

I propose in this text that Husserl’s response to his contemporaries, critics and immediate predecessors in Logical Investigations consists in the development of circular strategy. Husserl does not challenge psychologsim, empiricism or neo-Kantianism by immediately assuming a position of epistemological primacy over these philosophies. To the contrary, Husserl philosophically challenges these positions by enacting a circularity that already underlies them. Husserl’s critical distance from these theories implies a methodological proximity which enables him to advance his phenomenological project with constant (...) backward reference to the theories he challenges. Husserl’s circular philosophy transforms the themes it investigates and the theories it criticizes, transforming itself in that process. (shrink)

I propose in this text that Husserl’s response to his contemporaries, critics and immediate predecessors in Logical Investigations consists in the development of circular strategy. Husserl does not challenge psychologsim, empiricism or neo-Kantianism by immediately assuming a position of epistemological primacy over these philosophies. To the contrary, Husserl philosophically challenges these positions by enacting a circularity that already underlies them. Husserl’s critical distance from these theories implies a methodological proximity which enables him to advance his phenomenological project with constant (...) backward reference to the theories he challenges. Husserl’s circular philosophy transforms the themes it investigates and the theories it criticizes, transforming itself in that process. (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)

Psychologism in logic is the doctrine that the semantic content of logical terms is in some way a feature of human psychology. We consider the historically influential version of the doctrine, Psychological Individualism, and the many counter-arguments to it. We then propose and assess various modifications to the doctrine that might allow it to avoid the classical objections. We call these Psychological Descriptivism, Teleological Cognitive Architecture, and Ideal Cognizers. These characterizations give some order to the wide range of (...) modern views that are seen as psychologistic because of one or another feature. Although these can avoid some of the classic objections to psychologism, some still hold. (shrink)

Psychologism in logic holds that logic is a branch of psychology. This view has been vigorously defended by John Stuart Mill and by a number of German philosophers of logic, notably Erdmann. Its chief critics have been Husserl and Frege and, to a lesser extent, Russell. Husserl set forth a profound and detailed critique of psychologism in Logical Investigations. This paper examines this critique. First, I explain why the psychologistic theory is attractive. Then I show that Husserl's (...) critique is not convincing, partly because he does not take the theory in its most plausible form and partly because he ignores certain important distinctions (for example, between what a statement is about and what it is true in virtue of). Then I raise two new objections to the psychologistic theory. The purpose of this paper is to suggest that the psychologistic theory remains an important and serious position from which we can learn much about the status of logic. (shrink)

Psychologism is a philosophical ideology that seeks to explain the principles of logic, metaphysics, and epistemology as psychological phenomena. Psychologism has been the storm center of concerted criticisms since the nineteenth century, and is thought by many to have been refuted once and for all by Kant, Frege, Husserl, and others. The project of accounting for objective philosophical or mathematical truths in terms of subjective psychological states has been largely discredited in mainstream analytic thought. Ironically, psychologism has (...) resurfaced in unexpected guises in the form of intuitionistic logic and mathematics, cognitivism, and naturalized epistemology. I examine some of the principal objections to psychologism – distinguishing roughly between good and bad or philosophically acceptable versus unacceptable psychologism – and consider the extent to which a new wave of psychologism may be gaining prominence in contemporary philosophy, and the light its successes and failures may shed on the original concept and underlying perspective of classical psychologism. (shrink)

This essay discusses Peirce’s appeal to logical machines as an argument against psychologism. It also contends that some of Peirce’s anti-psychologistic remarks on logic contain interesting premonitions arising from his perception of the asymmetry of proof complexity in monadic and relational logical calculi that were only given full formulation and explication in the early twentieth century through Church’s Theorem and Hilbert’s broad-ranging Entscheidungsproblem.

This essay discusses Peirce’s appeal to logical machines as an argument against psychologism. It also contends that some of Peirce’s anti-psychologistic remarks on logic contain interesting premonitions arising from his perception of the asymmetry of proof complexity in monadic and relational logical calculi that were only given full formulation and explication in the early twentieth century through Church’s Theorem and Hilbert’s broad-ranging Entscheidungsproblem.

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.

Students often study logic on the assumption that it provides a normative guide to reasoning in English. In particular, they are taught to associate connectives like “and” with counterparts in Sentential Logic. English conditionals go over to formulas with → as principal connective. The well-known difficulties that arise from such translation are not emphasized. The result is the conviction that ordinary reasoning is faulty when discordant with the usual representation in standard logic. Psychologists are particularly susceptible to this attitude.

Logic is a celebrated representation language because of its formal generality. But there are two senses in which a logic may be considered general, one that concerns a technical ability to discriminate between different types of individuals, and another that concerns constitutive norms for reasoning as such. This essay embraces the former, permutation-invariance conception of logic and rejects the latter, Fregean conception of logic. The question of how to apply logic under this pure invariantist view is addressed, and a methodology (...) is given. The pure invariantist view is contrasted with logical pluralism, and a methodology for applied logic is demonstrated in remarks on a variety of issues concerning non-monotonic logic and non-monotonic inference, including Charles Morgan’s impossibility results for non-monotonic logic, David Makinson’s normative constraints for non-monotonic inference, and Igor Douven and Timothy Williamson’s proposed formal constraints on rational acceptance. (shrink)

In a recent article (Inquiry, Vol. 19 [1976]), J. W. Meiland addresses the issue of psychologism in logic, which holds that logic is a branch of psychology and that logical laws (such as the Principle of Non?Contradiction) are contingent upon the nature of the mind. Meiland examines Husserl's critique of psychologism, argues that Husserl is not convincing, and offers two new objections to the psychologistic thesis. In this paper I attempt to rebut those objections. In question are (...) the acceptable criteria for determining the possibility or impossibility of systems of logic significantly different from our own. I argue that a criteriological application of our accepted laws of logic to this question commits a circular fallacy. I then argue that, even if we accept logical consistency as a criterion for possibility, a plausible argument for the possibility of valid alternative logics can be constructed by using the functionalist analogy between minds and automata. Finally, I attempt to rebut the claim that in logic the only changes possible are conceptual changes that would not permit a proposition to be both true and false. (shrink)

The aim of the paper is to present the historical context and the motivation of an investigation still in progress, together with a sketch of some of its results. It starts with a brief description of the nature and history of cognitive science. The relation of cognitive science to logic is then considered, from which consideration a conception of logic as a descriptive and mentalist discipline emerges. Such conception clashes with Frege's antipsychologism. The purpose of the investigation is to refute (...) Frege's arguments, considered as objections to the view that there are two logics, both mentalist, one descriptive and one normative.O objetivo do trabalho é apresentar o contexto histórico, as motivações e um esboço de alguns resultados de uma pesquisa ainda não concluída. Primeiro fala-se um pouco da Ciência Cognitiva - de suas características gerais, de sua história, de sua relação com a Epistemologia. Considera-se depois sua relação com a Lógica, emergindo daí uma concepção da Lógica como descritiva e mentalista. Esta concepção choca-se com o antipsicologismo de Frege. A meta da pesquisa é refutar os argumentos de Frege enquanto objeções à tese de que existem duas lógicas, ambas mentalistas, uma descritiva e outra normativa. (shrink)

According to the Explanatory Problem with Frege's Platonism about Thoughts, the sharp separation between the psychological and the logical on which Frege famously insists is too sharp, leaving Frege no resources to show how it could be legitimate to invoke logical laws in an explanation of our activities of thinking. I argue that there is room in Frege's philosophy for such justificatory explanations. To see how, we need first to understand correctly the lesson of Frege's attack on (...) class='Hi'>psychologism as fundamentally marking a contrast between justification and explanation, and, second, we must take Frege to be committed to the idea that the laws of truth are normatively constitutive for the process of thinking. (shrink)

Contemporary logicians have expanded upon the old notions of psychologism in logic and proposed new, weakened versions of it. Those weakened versions postulate that psychologistic logic does not have to inform about the ontology or metaphysics of reasoning. Instead, logic applied in cognitive science could serve as one of many paradigms for making empirical predictions about the observable process of human reasoning. The purpose of this article is to entertain this notion and answer the question: what properties should a (...) logical system formally representing actual human reasoning have? Based on the existing evidence from cognitive science and neuroscience we identified three potential candidates: context-sensitivity (satisfied for example by adaptive logics), content-sensitivity (satisfied by non-Fregean logics) and probabilism (satisfied for example by fuzzy logics). (shrink)

This paper addresses the question whether the past couple of decades of formal research in belief revision offers evidence of a new psychologism in logic. In the first part I examine five potential arguments in favour of this thesis and find them all wanting. In the second part of the paper I argue that belief revision research has climbed up a hierarchy of models for the change of doxastic states that appear to be clearly normative at the bottom, but (...) are more amenable to an empirical-descriptive interpretation on higher levels. I conclude that this observation might offer a foothold for the thesis that there is a new psychologism in logic. (shrink)

Frege is an anti-psychologist about logic who takes logic to be sharply distinguished from psychology. However, Frege also takes judgment, which seems to be a subject of psychology, to be essential to logic. Van der Schaar attempts to explain away this tension by arguing that judgments relevant to logic in Frege are not mental actions psychology deals with. Against this reading, I show that for Frege, judgments are mental actions consistently. The tension in question should be explained away by clarifying (...) the sense in which judgment is essential to logic for Frege. He takes judgment to be essential to logic because he thinks that logic requires judgments to be performed. Logic requires logicians to be committed to truth, and it is by judgments that we are committed to truth. If Frege takes judgment to be essential to logic only in this sense, he is not thereby committed to logical psychologism. (shrink)

In the nineteenth century, philosophy was at a crossroads. While the natural and technical sciences were developing in an unprecedented fashion, philosophy seemed to be stalled. Inspired by the progress of the natural sciences, many philosophers attempted to make such progress in philosophy and make philosophy a truly scientific discipline. This effort was also reflected in the philosophy of the Lvov-Warsaw school. While its founder, Kazimierz Twardowski, following his teacher Franz Brentano, promoted psychology as a method of scientific philosophy, one (...) of his first students, Jan Łukasiewicz, was convinced that mathematical logic was such a method. To use mathematical logic as a tool, Łukasiewicz had to, however, argue convincingly that logic is an independent science and hence is not a part of psychology, i.e., arguing for anti-psychologism in logic. He initially adopted the arguments provided by Husserl, then celebrated as a proponent of anti-psychologism, and Frege’s views. When Łukasiewicz developed, however, his systems of many-valued logic, he denied almost all the principles that characterise Husserl and Frege’s anti-psychologism, i.e., the objectivity of the laws of logic, the existence of apodictic propositions, and the distinction between a priori and empirical sciences. He was, however, a proponent of anti-psychologism up to the end of his life. The aim of my paper is to introduce Łukasiewicz’s unique concept of anti-psychologism that significantly affected the views of mathematical logic in the Lvov-Warsaw School, and the views of his colleagues which helped him develop the concept. (shrink)

Corcoran, J. 2007. Psychologism. American Philosophy: an Encyclopedia. Eds. John Lachs and Robert Talisse. New York: Routledge. Pages 628-9. -/- Psychologism with respect to a given branch of knowledge, in the broadest neutral sense, is the view that the branch is ultimately reducible to, or at least is essentially dependent on, psychology. The parallel with logicism is incomplete. Logicism with respect to a given branch of knowledge is the view that the branch is ultimately reducible to logic. Every (...) branch of knowledge depends on logic. Psychologism is found in several fields including history, political science, economics, ethics, epistemology, linguistics, aesthetics, mathematics, and logic. Logicism is found mainly in branches of mathematics: number theory, analysis, and, more rarely, geometry. Although the ambiguous term ‘psychologism’ has senses with entirely descriptive connotations, it is widely used in senses that are derogatory. No writers with any appreciation of this point will label their own views as psychologistic. It is usually used pejoratively by people who disapprove of psychologism. The term ‘scientism’ is similar in that it too has both pejorative and descriptive senses but its descriptive senses are rarely used any more. It is almost a law of linguistics that the negative connotations tend to drive out the neutral and the positive. Dictionaries sometimes mark both words with a usage label such as “Usually disparaging”. In this article, the word is used descriptively mainly because there are many psychologistic views that are perfectly respectable and even endorsed by people who would be offended to have their views labeled psychologism. A person who subscribes to logicism is called a logicist, but there is no standard word for a person who subscribes to psychologism. ‘Psychologist’, which is not suitable, occurs in this sense. ‘Psychologician’, with stress on the second syllable as in ‘psychologist’, has been proposed. In the last century, some of the most prominent forms of psychologism pertained to logic; the rest of this article treats only such forms. Psychologism in logic is very “natural”. After all, logic studies reasoning, which is done by the mind, whose nature and functioning is studied in psychology—using the word ‘psychology’ in its broadest etymological sense. (shrink)

Wittgenstein’s Tractatus construes the nature of reasoning in a manner which sharply conflicts with the conventional wisdom that logic is normative, not descriptive of thought. For although we sometimes seem to reason incorrectly, Wittgenstein denies that we can make logical mistakes (5.473). My aim in this paper is to show that the Tractatus provides us with good reasons to rethink some of the central assumptions that are standardly made in thinking about the relation between logic and thought. In particular, (...) the rejection of logical mistakes is to be understood in connection with Wittgenstein’s non-psychological approach to the thinking subject (5.641). On Wittgenstein's view, inference, understanding, and meaning are holistically related; cases of defective reasoning are to be explained in terms of a defective grasp of meaning which manifests in an indeterminate use of signs. Invalid reasoning therefore does not count for Wittgenstein as a species of reasoning, but rather as the mere illusion of reasoning. The rejection of logical mistakes thus gives voice to a radical disjunctivist approach. (shrink)

This paper is about the topic of psychologism in the work of Kazimierz Twardowski and my aim is to revisit this important issue in light of recent publications from, and on Twardowski’s works. I will first examine the genesis of psychologism in the young Twardowski’s work; secondly, I will examine Twardowski’s picture theory of meaning and Husserl’s criticism in Logical Investigations; the third part is about Twardowski’s recognition and criticism of his psychologism in his lectures on (...) the psychology of thinking; the fourth and fifth parts provide an overview of Twardowski’s paper “Actions and Products” while the sixth part addresses the psychologism issue in the last part of this paper through the delineation of psychology and the humanities. I shall conclude this study with a brief assessment of Twardowski’s solution to psychologism. (shrink)

By tracing the general evolution of HusserI’s theory of logic and mathematics, this essay explores Husserl’s identification and strategic overcoming of the two forms of psychologism--Iogical psychologism and transcendental psychologism--that bar the way to rigorous phenomenological inquiry. In the early works “On the Concept of Number” and the Philosophie der Arithmetik Husserl himself falls victim to a particular form of logical psychologism. By the time of the Logical Investigations this problem has been dealt with: (...) the method of eidetic intuition enables an account of the “origins” of logical and mathematical concepts without reducing such concepts to mere predicates of mental acts. The task of Formal and Transcendental Logic is to disclose the more pervasive problem of transcendental psychologism, one that taints even the theory of pure logic articulated in the Logical Investigations. A radical solution is provided through the development of an “ultimate logic” of transcendental subjectivity. (shrink)

By tracing the general evolution of HusserI’s theory of logic and mathematics, this essay explores Husserl’s identification and strategic overcoming of the two forms of psychologism--Iogical psychologism and transcendental psychologism--that bar the way to rigorous phenomenological inquiry. In the early works “On the Concept of Number” and the Philosophie der Arithmetik Husserl himself falls victim to a particular form of logical psychologism. By the time of the Logical Investigations this problem has been dealt with: (...) the method of eidetic intuition enables an account of the “origins” of logical and mathematical concepts without reducing such concepts to mere predicates of mental acts. The task of Formal and Transcendental Logic is to disclose the more pervasive problem of transcendental psychologism, one that taints even the theory of pure logic articulated in the Logical Investigations. A radical solution is provided through the development of an “ultimate logic” of transcendental subjectivity. (shrink)

The term ‘psychologism’ is normally used for the doctrine that logical and mathematical truths must be explained in terms of psychological truths (see Kusch 1995 and 2011). As such, the term is typically pejorative: the widespread consensus is that psychologism in this sense is a paradigm of philosophical error, a gross mistake that was identified and conclusively refuted by Frege and Husserl.

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)

The aim of the paper is to try and make one’s ideas clearer about such concepts as “logic,” “psychology,” “mind,” “normativity,” rationality,” as they were conceived by Peirce, in order to elucidate his genuine position as far as the relationship between logic and pychology is concerned, whether he was or was not a straightforward “anti psychologist” in logic, and from such analyses, to make some suggestions about the contemporary relevance of Peirce’s original views on such isues.

This critical notice explores the distinction central to analytic philosophy between the logical study of the normative principles governing rational thought and the psychological study of the processes of thinking. Thomas Nagel maintains (1) that the fundamental principles of reasoning have normative force and make claims to universal validity; (2) that the fundamental principles of reasoning cannot be construed as the expression of contingent forms of life; and (3) that the identification of fundamental principles of reasoning should be completely (...) independent of psychological facts about how people reason. The notice draws upon intuitionist critiques of classical logic and the Allais paradox in expected utility theory to argue that (1) can be consistently combined with the denial of (2) and (3). (shrink)