Logical Investigations

Dedication
Contents
Preface • Michael Dummett
Introduction • Dermot Moran
Select bibliography
Translator’s Introduction (Abridged)
Foreword to First German Edition, Volume I (1900)
Foreword to Second German Edition, Volume I (1913)
Prolegomena to Pure Logic: Volume I of the German Editions
	Introduction
		§1 The controversy regarding the definition of logic and the essential content of its doctrines
		§2 Necessity of a renewed discussion of questions of principle
		§3 Disputed questions. The path to be entered
	1 Logic as a normative and, in particular, as a practical discipline
		§4 The theoretical incompleteness of the separate sciences
		§5 The theoretical completion of the separate sciences by metaphysics and theory of science
		§6 The possibility and justification of logic as theory of science
		§7 Continuation. The three most noteworthy peculiarities of grounded validations
		§8 The relation of these peculiarities to the possibility of science and the theory of science
		§9 Methodical modes of procedure in the sciences are in part validatory, in part auxiliary devices towards validations
		§10 The ideas of theory and science as problems of the theory of science
		§11 Logic or theory of science as normative discipline and as technology
		§12 Relevant definitions of logic
	2 Theoretical disciplines as thefoundation of normative disciplines
		§13 The controversy regarding the practical character of logic
		§14 The concept of a normative science. The basic standard or principle that gives it unity
		§15 Normative disciplines and technologies
		§16 Theoretical disciplines as the foundation of normative disciplines
	3 Psychologism, its arguments and its attitude to the usual counter-arguments
		§17 The disputed question as to whether the essential theoretical foundations of normative logic lie in psychology
		§18 The line of proof of the psychologistic thinkers
		§19 The usual arguments of the opposition and the psychologistic rejoinder
		§20 A gap in the psychologistic line of proof
	4 Empiricistic consequences of psychologism
		§21 Characterizing two empiricistic consequences of the psychologistic standpoint, and their refutation
		§22 The laws of thought as supposed laws of nature which operate in isolation as causes of rational thought
		§23 A third consequence of psychologism, and its refutation
		§24 Continuation
	5 Psychological interpretations of basic logical principles
		§25 The law of contradiction in the psychologistic interpretation of Mill and Spencer
		§26 Mill’s psychological interpretation of the principle yields no law, but a wholly vague, and scientifically unproven, empirical proposition
		Appendix to the last two sections
		§27 Analogous objections against remaining psychological interpretations of our logical principle. Ambiguities as sources of delusion
		§28 The supposed two-sidedness of the principle of contradiction, in virtue of which it should be taken both as a natural law of thinking, and as a normal law for its logical regulation
		§29 Continuation. Sigwart’s doctrine
	6 Syllogistic inferences psychologistically considered. Syllogistic and chemical formulae
		§30 Attempts at interpreting syllogistic principles psychologically
		§31 Syllogistic and chemical formulae
	7 Psychologism as a sceptical relativism
		§32 The ideal conditions for the possibility of a theory as such. The strict concept of scepticism
		§33 Scepticism in the metaphysical sense
		§34 The concept of relativism and its specific forms
		§35 Critique of individual relativism
		§36 Critique of specific relativism and, in particular, of anthropologism
		§37 General observation. The concept of relativism in an extended sense
		§38 Psychologism in all its forms is a relativism
		§39 Anthropologism in Sigwart’s Logic
		§40 Anthropologism in the Logic of B. Erdmann
	8 The psychologistic prejudices
		§41 First prejudice
		§42 Elucidations
		§43 A look back at the opposed arguments of idealism. Their defects and their justified sense
		§44 Second prejudice
		§45 Refutation. Pure mathematics would likewise be made a branch of psychology
		§46 The research domain of pure logic is, like that of mathematics, an ideal domain
		§47 Confirmatory indications given by the basic notions of logic and the sense of logical laws
		§48 The decisive differences
		§49 Third prejudice. Logic as the theory of evidence
		§50 Transformation of logical propositions into equivalent propositions about the ideal conditions for the evidence of judgement. The resultant propositions are not psychological
		§51 The decisive points in this dispute
	9 Logic and the principle of the economy of thought
		§52 Introductory
		§53 The teleological character of the principle of Mach and Avenarius and the scientific meaning of an ‘economy of thought’ (Denkökonomik)
		§54 Closer treatment of the justified ends of an ‘economy of thought’, in the sphere, mainly, of purely deductive methodology. Its relation to a logical technology
		§55 The meaninglessness of an economy of thought for pure logic and epistemology, and its relation to psychology
		§56 Continuation. The ὕστερον πρότερον involved inany foundation of pure logic on an economy of thought
	10 End of our critical treatments
		§57 Queries regarding readily formed misunderstandings of our logical endeavours
		§58 Our links with great thinkers of the past and, in the first place, with Kant
		§59 Links with Herbart and Lotze
		§60 Links with Leibniz
		§61 Need for special investigations to provide an epistemological justification and partial realization of the Idea of pure logic
		Appendix
	11 The idea of Pure Logic
		§62 The unity of science. The interconnection of things and the interconnection of truths
		§63 Continuation. The unity of theory
		§64 The essential and extra-essential principles that give science unity. Abstract, concrete and normative sciences
		§65 The question as to the ideal conditions of the possibility of science or of theory in general. A. The question as it relates to actual knowledge
		§66 B. The question as it relates to the content of knowledge
		§67 The tasks of pure logic. First: the fixing of the pure categories of meaning, the pure categories of objects and their law-governed combinations
		§68 Secondly: the laws and theories which have their grounds in these categories
		§69 Thirdly: the theory of the possible forms of theories or the pure theory of manifolds
		§70 Elucidation of the Idea of a pure theory of manifolds
		§71 Division of labour. The achievement of the mathematicians and that of the philosophers
		§72 Broadening of the Idea of pure logic. The pure theory of probability as a pure theory of empirical knowledge
Investigations into phenomenology and the theory of knowledge, part I: Volume II, Part I of the German Editions
	Introduction
		§1 The necessity of phenomenological investigations as a preliminary to the epistemological criticism and clarification of pure logic
		§2 Elucidation of the aims of such investigations
		§3 The difficulties of pure phenomenological analysis
		§4 It is essential to keep in mind the grammatical side of our logical experiences
		§5 Statement of the main aims of the following analytical investigations
		§6 Additional Notes
		§7 ‘Freedom from presuppositions’ as a principle in epistemological investigations
	Investigation I: Expression and meaning
		1 Essential distinctions
			§1 An ambiguity in the term ‘sign’
			§2 The essence of indication
			§3 Two senses of ‘demonstration’ (‘indication’ and ‘proof’)
			§4 Digression on the origin of indication in association
			§5 Expressions as meaningful signs. Setting a side of a sense of ‘expression’ not relevant for our purpose
			§6 Questions as to the phenomenological and intentional distinctions which pertain to expressions as such
			§7 Expressions as they function in communication
			§8 Expressions in solitary life
			§9 Phenomenological distinctions between the physical appearance of the expression, and the sense-giving and sense-fulfilling act
			§10 The phenomenological unity of these acts
			§11 The ideal distinctions between (I) expression and meaning as ideal unities
			§12 Continuation: the expressed objectivity
			§13 Connection between meaning and objective reference
			§14 Content as object, content as fulfilling sense and content as sense or meaning simpliciter
			§15 The equivocations in talk of meaning and meaninglessness connected with these distinctions
			§16 Continuation: meaning and connotation
		2 Towards a characterization of the acts which confer meaning
			§17 Illustrative mental pictures as putative meanings
			§18 Continuation of the above. Arguments and counter-arguments
			§19 Understanding without intuition
			§20 Thought without intuition and the ‘surrogative function’ of signs
			§21 A difficulty regarding our necessary recourse to corresponding intuitions in order to clarify meanings or to know truths resting on them
			§22 Varying marks of understanding and the ‘quality of familiarity’
			§23 Apperception as connected with expression and with intuitive presentations
		3 Fluctuation in meaning and the ideality of unities of meaning
			§24 Introduction
			§25 Relations of coincidence among the contents of intimation and naming
			§26 Essentially occasional and objective expressions
			§27 Other sorts of fluctuating expressions
			§28 Variations in meanings as variations in the act of meaning
			§29 Pure logic and ideal meanings
		4 The phenomenological and ideal content of the experiences of meaning
			§30 The content of the expressive experience taken in its psychological sense and in the sense of a unified meaning
			§31 The act-character of meaning and the ideally unified meaning
			§32 The ideality of meanings is no ideality in the normative sense
			§33 The concepts meaning and concept (in the sense of species) do not coincide
			§34 In the act of meaning we are not conscious of meaning as an object
			§35 Meanings ‘in themselves’ and meanings expressed
	Investigation II: The ideal unity of the species and modern theories of abstraction
		Introduction
		1 Universal objects and the consciousness of universality
			§1 We are conscious of universal objects in acts which differ essentially from those in which we are conscious of individual objects
			§2 The indispensability of talk about universal objects
			§3 Must the unity of the Species be regarded as a spurious unity? Identity and exact likeness
			§4 Objections to the reduction of ideal unity to dispersed multiplicity
			§5 Continuation. The controversy between John Stuart Mill and H. Spencer
			§6 Transition to the following chapters
		2 The psychological hypostatization of the universal
			§7 The metaphysical and psychological hypostatization of the universal. Nominalism
			§8 A deceptive line of thought
			§9 Locke’s doctrine of abstract ideas
			§10 Criticism
			§11 Locke’s universal triangle
			§12 The doctrine of generic images
		3 Abstraction and attention
			§13 Nominalistic theories which regard abstraction as an achievement of attention
			§14 Objections to any and every form of nominalism. (a) The lack of a descriptive fixation of aims
			§15 (b) The origin of modern nominalism as an exaggerated reaction to Locke’s doctrine of generalideas. The essential character of this nominalism, and of the theory of abstraction in terms of attention
			§16 (c) Generality of psychological function and generality as a meaning-form. Different senses of the relation of a universal to an extension
			§17 (d) Application to the critique of nominalism
			§18 The doctrine of attention as a generalizing power
			§19 Objections. (a) Exclusive attention to one attributive aspect does not remove its individuality
			§20 (b) Refutation of the argument from geometrical thought
			§21 The difference between attending to a non-independent moment of an intuited object and attending to the corresponding attribute in specie
			§22 Fundamental deficiencies in the phenomenological analysis of attention
			§23 Significant talk of attention embraces the whole sphere of thinking and not merely the sphere of intuition
		4 Abstraction and representation
			§24 The general idea as a device for economizing thought
			§25 Whether general representation can serve as an essential characteristic of our general presentations
			§26 Continuation. The varying modifications of the consciousness of generality, and the sensuous intuition
			§27 The justifiable sense of general representation
			§28 Representation as substitution. Locke and Berkeley
			§29 Critique of Berkeley’s doctrine of representation
			§30 Continuation. Berkeley’s argument from geometrical demonstrations
			§31 The main source of the errors that we have indicated
		5 Phenomenological study of Hume’s theory of abstraction
			§32 Hume’s dependence on Berkeley
			§33 Hume’s critique of abstract ideas and its supposed outcome. His ignoring of pivotal phenomenological issues
			§34 Reduction of Hume’s investigation to two questions
			§35 The guiding principle and outcome of Hume’s doctrine of abstraction and the main thoughts in which it is worked out
			§36 Hume’s doctrine of the distinctio rationis in its moderate and its radical interpretation
			§37 Objections to this doctrine in its radical interpretation
			Notes
			§38 Transference of our scepticism from abstract part-contents to all parts whatsoever
			§39 The extreme limit of scepticism and its refutation
			Appendix
		6 Separation of varying concepts of abstraction and abstract
			§40 Confusion of concepts of abstraction and abstract concerned with non-independent part-contents, on the one hand, and Species on the other
			§41 Separation of concepts grouped about the concept of the non-independent content
			§42 Separation of the concepts that group themselves about the concept of the Species
Notes
Index