Assertion plays a crucial dual role in Frege's conception of logic, a formal and a transcendental one. A recurrent complaint is that Frege's inclusion of the judgement-stroke in the Begriffsschrift is either in tension with his anti-psychologism or wholly superfluous. Assertion, the objection goes, is at best of merely psychological significance. In this paper, I defend Frege against the objection by giving reasons for recognising the central logical significance of assertion in both its formal and its transcendental role.

Concepts are highly theoretical entities. One cannot study them empirically without committing oneself to substantial preliminary assumptions. Among the competing theories of concepts and categorization developed by psychologists in the last thirty years, the implicit theoretical assumption that what falls under a concept is determined by description () has never been seriously challenged. I present a nondescriptionist theory of our most basic concepts, which include (1) stuffs (gold, milk), (2) real kinds (cat, chair), and (3) individuals (Mama, Bill Clinton, the (...) Empire State Building). On the basis of something important that all three have in common, our earliest and most basic concepts of substances are identical in structure. The membership of the category like that of is a natural unit in nature, to which the concept does something like pointing, and continues to point despite large changes in the properties the thinker represents the unit as having. For example, large changes can occur in the way a child identifies cats and the things it is willing to call without affecting the extension of its word The difficulty is to cash in the metaphor of in this context. Having substance concepts need not depend on knowing words, but language interacts with substance concepts, completely transforming the conceptual repertoire. I will discuss how public language plays a crucial role in both the acquisition of substance concepts and their completed structure. (shrink)

In the opening to his late essay, Der Gedanke, Frege asserts without qualification that the word "true" points the way for logic. But in a short piece from his Nachlass entitled "My Basic Logical Insights", Frege writes that the word true makes an unsuccessful attempt to point to the essence of logic, asserting instead that "what really pertains to logic lies not in the word "true" but in the assertoric force with which the sentence is uttered". Properly understanding what Frege (...) takes to be at issue here is crucial for understanding his conception of logic and, in particular, what he takes to be its normative status vis-à-vis judgement, assertion, and inference. In this paper, I focus my attention on clarifying the latter claim and Frege's motivations for making it, exposing what I take to be a fundamental tension in Frege's conception of logic. Finally, I discuss whether Frege's deployment of the horizontal in his mature Begriffsschrift helps to resolve this tension. (shrink)

The aim of this paper is to give a detailed reconstruction of Frege's solution to his puzzle about the cognitive function of truth, which is this: On the one hand, the concept of truth seems to play an essential role in acquiring knowledge because the transition from the mere hypothetical assumption that p to the acknowledgement of its truth is a crucial step in acquiring the knowledge that p, while, on the other hand, this concept seems to be completely redundant (...) because the sense of the word 'true' does not make any essential contribution to the senses of the sentences in which it occurs. (shrink)

Everyone has mistaken one thing for another, such as a stranger for an acquaintance. A person who has mistaken two things, Joseph Camp argues, even on a massive scale, is still capable of logical thought. In order to make that idea precise, one needs a logic of confused thought that is blind to the distinction between the objects that have been confused. Confused thought and language cannot be characterized as true or false even though reasoning conducted in such language can (...) be classified as valid or invalid. To the extent that philosophers have addressed this issue at all, they take it for granted that confusion is a kind of ambiguity. Camp rejects this notion; his fundamental claim is that confusion is not a mental state. To attribute confusion to someone is to take up a paternalistic stance in evaluating his reasoning. Camp proposes a novel characterization of confusion, and then demonstrates its fruitfulness with several applications in the history of philosophy and the history of science. (shrink)

I argued that Frege does not have a metatheory in the following sense: the justifications he offers for his basic laws and rules of inference neither employ nor require a truth-predicate or metalinguistic variables. In ‘Does Frege Use a Truth-predicate in his "Justification" of the Laws of Logic?’, Dirk Greimann disputes this. As Greimann interprets Frege, (i) Frege's remarks commit him to giving a metatheoretic justification of the basic laws and rules of his logic, and (ii) Frege actually gives such (...) a justification in the early sections of Grundgesetze—although the truth-predicate that Frege employs is a non-standard one: it is neither a predicate that holds of all and only true sentences nor a predicate that holds of all and only true thoughts. I argue that Greimann's interpretation is not, in the end, true to the text, and that his non-standard view of what is required of a Tarskian truth-predicate is ultimately not viable. (shrink)

Joan Weiner has recently claimed that Frege neither uses, nor has any need to use, a truth-predicate in his justification of the logical laws. She argues that because of the assimilation of sentences to proper names in his system, Frege does not need to make use of the Quinean device of semantic ascent in order to formulate the logical laws, and that the predicate ‘is the True’, which is used in Frege's justification, is not to be considered as a truth-predicate, (...) because it does not apply to true sentences or true thoughts. The present paper aims to show that Frege needs to use, and does use, a truth-predicate in this context. It is argued, first, that Frege needs to use a truthpredicate in order to show that the truth of the logical laws is evident from the senses of the sentences by means of which they are formulated, and second, that the predicate that he actually uses, ‘is the True’, must be considered as a truth-predicate in the relevant sense, because it can be used and is actually used by Frege to explain the truth-conditions of thoughts. To defend this interpretation, it is discussed whether the explanatory use of ‘is the True’ in Frege's system is compatible with his deflationary analysis of ‘true’. The paper's conclusion is that there is indeed a conflict here; but, from Frege's point of view, this conflict is due merely to the logical imperfection of natural language and does not affect the proper system but only its propaedeutic. (shrink)

It is commonly assumed that the conception of truth defended by Frege in his mature period is characterized by the view that truth is not the property denoted by the predicate 'is true', but the object named by true sentences. In the present paper, I wish to make plausible an alternative interpretation according to which Frege's conception is characterized by the view that truth is what is expressed in natural language by the "form of the assertoric sentence". So construed, truth (...) is neither an object (like the True) nor a property (like the Bedeutung of the predicate 'is true') but something of a very special kind that belongs to the same logical category as the logical relations (like subsumption). The main argument justifying this interpretation is that Frege's explication of truth does not hold of the True, but only of truth, considered as what is expressed by the form of the assertoric sentence. (shrink)

Frege seems to hold two incompatible theses:(i) that sentences differing in structure can yet express the same sense; and (ii) that the senses of the meaningful parts of a complex term are determinate parts of the sense of the term. Dummett offered a solution, distinguishing analysis from decomposition. The present paper offers an embellishment of Dummett?s distinction by providing a way of depicting the internal structures of complex senses?determinate structures that yield distinct decompositions. Decomposition is then shown to be adequate (...) as a foundation for the informativity and analyticity of logic. (shrink)

The syntax of Frege's scientific language is commonly taken to be characterized by two oddities: the representation of the intended illocutionary role of sentences by a special sign, the judgement-stroke, and the treatment of sentences as a species of singular terms. In this paper, an alternative view is defended. The main theses are: the syntax of Frege's scientific language aims at an explication of the logical form of judgements; the judgement-stroke is, therefore, a truth-operator, not a pragmatic operator; in Frege's (...) first system, '⊦ Δ' expresses that the circumstance Δ is a fact, and in his second system that the truth-value - Δ is the True; in both systems, the judgement-stroke is construed as a sign sui generis, not as a genuine predicate; its counterpart in natural language is the syntactic "form of assertoric sentences", not the truth-predicate; neither in Frege's first nor in his second system sentences are treated as singular terms. (shrink)

The paper maintains (1) that Frege's quantification of sentence positions motivates his identification of sentences as proper names of truth-values; (2) that this identification is fully compatible with the 'context principle'; (3) that the relation of a thought to its truth-value is the primary case of the relation of sense to meaning. The paper offers a reconstruction of Frege's defense of (1) in pp. 33-35 of "On Sense and Meaning".

The founder of modern logic and grandfather of analytic philosophy was 70 years old when he published his paper 'Der Gedanke' (The Thought ) in 1918. This essay contains some of Gottlob Frege's deepest and most provocative reflections on the concept of truth, and it will play a prominent role in my lectures. The plan for my lectures is as follows. What is it that is (primarily) true or false? 'Thoughts', is Frege's answer. In §1, I shall explain and defend (...) this answer. In §2, I shall briefly consider his enthymematic argument for the conclusion that the word 'true' resists any attempt at defining it. In §3, I shall discuss his thesis that the thought that things are thus and so is identical with the thought that it is true that things are thus and so. The reasons we are offered for this thesis will be found wanting. In §4, I shall comment extensively on Frege's claim that, in a non-formal language like the one I am currently trying to speak, we can say whatever we want to say without ever using the word 'true' or any of its synonyms. I will reject the propositional-redundancy claim, endorse the assertive-redundancy claim and deny the connection Frege ascribes to them. In his classic 1892 paper 'Über Sinn und Bedeutung' (On Sense and Signification) Frege argues that truth-values are objects. In §5, I shall scrutinize his argument. In §6, I will show that in Frege's ideography (Begriffsschrift) truth, far from being redundant, is omnipresent. The final §7 is again on truth-bearers, this time as a topic in the theory of intentionality and in metaphysics. In the course of discussing Frege's views on the objecthood, the objectivity of thoughts and the timelessness of truth(s), I will plead for a somewhat mitigated Platonism. (shrink)