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)

The aim of this paper is to clarify the truth-functional interpretation of the logical connective of the material implication. The importance of such clarification lies in the fact that it allows avoiding the supposed paradoxes introduced by C. I. Lewis (1918). I argue that an adequate understanding of the history and purposes of logic is enough to dissolve them away. The defense is based on an exposition of propositional compositionalism. To compare, I also present Stalnaker’s (1968) alternative that seeks (...) to explain the implicit concept of conditionality of conditionals assertions. In order to reinforce my aim I expound the twelve different meanings of ‘implication’ stated by Corcoran (1993) in order to hold that a proper understanding of these meanings allows us to avoid ambiguities and confusions. Finally, I expect to show that despite the possible alternatives, compositionalism is still the best explanation for the truth-functionality account of logical connectives. (shrink)

Ever since the publication of Kripke’s Wittgenstein on Rules and Private Language, there’s been a raging debate in philosophy of language over whether meaning and thought are, in some sense, normative. Most participants in the normativity wars seem to agree that some uses of meaningful expressions are semantically correct while disagreeing over whether this entails anything normative. But what is it to say that a use of an expression is semantically correct? On the so-called orthodox construal, it is to say (...) that it doesn’t result in a factual mistake, that is, in saying or thinking something false. On an alternative construal it is instead to say that it doesn’t result in a distinctively linguistic mistake, that is, in misusing the expression. It is natural to think that these two construals of semantic correctness are simply about different things and not in competition with each other. However, this is not the common view. Instead, several philosophers who subscribe to the orthodox construal have argued that the alternative construal of correctness as use in accordance with meaning doesn’t make any sense, partly because there are no clear cases of linguistic mistakes (Whiting 2016, Wikforss 2001). In this paper I develop and defend the idea that there’s a distinctively linguistic notion of correctness as use in accordance with meaning and argue that there are clear cases of linguistic mistakes. (shrink)

We present the details of a methodology for quality assurance in large medical terminologies and describe three algorithms that can help terminology developers and users to identify potential mistakes. The methodology is based in part on linguistic criteria and in part on logical and ontological principles governing sound classifications. We conclude by outlining the results of applying the methodology in the form of a taxonomy different types of errors and potential errors detected in SNOMED-CT.

A suggestion famously made by Peter Winch and carried through to present discussions holds that what constitutes the social as a kind consists of something shared – rules or practices commonly learned, internalized, or otherwise acquired by all members belonging to a society. This essays argues against the explanatory efficacy of appeals to this shared something as constitutive of a social kind by examining a violation of social norms or rules, viz., mistakes. I argue that an asymmetric relation exists (...) between the notion of mistakes and that of the social. In particular, mistakes do not presuppose a concept of the social, but the concept of the social requires prior specification of a category of mistakes. But no such prior specification proves possible. The very notion of a mistake is so inchoate that it makes it impossible to provide the kind of regimentation required for a rule-governed domain. Thus, there may be recognized mistakes even in the absence of a unified system or common knowledge of norms.Later writers attempt to avoid Winch's over-strong assumption that something shared and internal constitutes the social but cannot. Extending recent work by Stephen Turner, I argue that ``the social'' is not a domain that is susceptible to lawlike treatment, but rather a heterogeneous, motley collection. For absent the assumption of a shared something, no social object exists to be explained. So, I conclude, we have at present no clear way of marking out the social as a coherent or unified domain of inquiry. (shrink)

My first paper on the Is/Ought issue. The young Arthur Prior endorsed the Autonomy of Ethics, in the form of Hume’s No-Ought-From-Is (NOFI) but the later Prior developed a seemingly devastating counter-argument. I defend Prior's earlier logical thesis (albeit in a modified form) against his later self. However it is important to distinguish between three versions of the Autonomy of Ethics: Ontological, Semantic and Ontological. Ontological Autonomy is the thesis that moral judgments, to be true, must answer to a (...) realm of sui generis non-natural PROPERTIES. Semantic autonomy insists on a realm of sui generis non-natural PREDICATES which do not mean the same as any natural counterparts. Logical Autonomy maintains that moral conclusions cannot be derived from non-moral premises.-moral premises with the aid of logic alone. Logical Autonomy does not entail Semantic Autonomy and Semantic Autonomy does not entail Ontological Autonomy. But, given some plausible assumptions Ontological Autonomy entails Semantic Autonomy and given the conservativeness of logic – the idea that in a valid argument you don’t get out what you haven’t put in – Semantic Autonomy entails Logical Autonomy. So if Logical Autonomy is false – as Prior appears to prove – then Semantic and Ontological Autonomy would appear to be false too! I develop a version of Logical Autonomy (or NOFI) and vindicate it against Prior’s counterexamples, which are also counterexamples to the conservativeness of logic as traditionally conceived. The key concept here is an idea derived in part from Quine - that of INFERENCE-RELATIVE VACUITY. I prove that you cannot derive conclusions in which the moral terms appear non-vacuously from premises from which they are absent. But this is because you cannot derive conclusions in which ANY (non-logical) terms appear non-vacuously from premises from which they are absent Thus NOFI or Logical Autonomy comes out as an instance of the conservativeness of logic. This means that the reverse entailment that I have suggested turns out to be a mistake. The falsehood of Logical Autonomy would not entail either the falsehood Semantic Autonomy or the falsehood of Ontological Autonomy, since Semantic Autonomy only entails Logical Autonomy with the aid of the conservativeness of logic of which Logical Autonomy is simply an instance. Thus NOFI or Logical Autonomy is vindicated, but it turns out to be a less world-shattering thesis than some have supposed. It provides no support for either non-cognitivism or non-naturalism. (shrink)

Timothy Williamson has famously argued that the principle should be rejected. We analyze Williamson's argument and show that its key premise is ambiguous, and that when it is properly stated this premise no longer supports the argument against. After canvassing possible objections to our argument, we reflect upon some conclusions that suggest significant epistemological ramifications pertaining to the acquisition of knowledge from prior knowledge by deduction.

Logical pluralism is the view that there is more than one correct logic. Most logical pluralists think that logic is normative in the sense that you make a mistake if you accept the premisses of a valid argument but reject its conclusion. Some authors have argued that this combination is self-undermining: Suppose that L1 and L2 are correct logics that coincide except for the argument from Γ to φ, which is valid in L1 but invalid in L2. If (...) you accept all sentences in Γ, then, by normativity, you make a mistake if you reject φ. In order to avoid mistakes, you should accept φ or suspend judgment about φ. Both options are problematic for pluralism. Can pluralists avoid this worry by rejecting the normativity of logic? I argue that they cannot. All else being equal, the argument goes through even if logic is not normative. (shrink)

The need to distinguish between logical and extra-logical varieties of inference, entailment, validity, and consistency has played a prominent role in meta-ethical debates between expressivists and descriptivists. But, to date, the importance that matters of logical form play in these distinctions has been overlooked. That’s a mistake given the foundational place that logical form plays in our understanding of the difference between the logical and the extra-logical. This essay argues that descriptivists are better positioned (...) than their expressivist rivals to provide the needed account of logical form, and so better able to capture the needed distinctions. This finding is significant for several reasons: First, it provides a new argument against expressivism. Second, it reveals that descriptivists can make use of this new argument only if they are willing to take a controversial—but plausible—stand on claims about the nature and foundations of logic. (shrink)

In the present version of these lecture notes only a number of typos and a few glaring mistakes have been corrected. Thanks to Paul Dekker for his help in this respect. No attempt has been been made to update the original text or to incorporate new insights and approaches. For a more recent overview, see our ‘Questions’ in the Handbook of Logic and Language (edited by Johan van Benthem and Alice ter Meulen, Elsevier, 1997).

This paper corrects a mistake I saw students make but I have yet to see in print. The mistake is thinking that logically equivalent propositions have the same counterexamples—always. Of course, it is often the case that logically equivalent propositions have the same counterexamples: “every number that is prime is odd” has the same counterexamples as “every number that is not odd is not prime”. The set of numbers satisfying “prime but not odd” is the same as the set of (...) numbers satisfying “not odd but not not-prime”. The mistake is thinking that every two logically-equivalent false universal propositions have the same counterexamples. Only false universal propositions have counterexamples. A counterexample for “every two logically-equivalent false universal propositions have the same counterexamples” is two logically-equivalent false universal propositions not having the same counterexamples. The following counterexample arose naturally in my sophomore deductive logic course in a discussion of inner and outer converses. “Every even number precedes every odd number” is counterexemplified only by even numbers, whereas its equivalent “Every odd number is preceded by every even number” is counterexemplified only by odd numbers. Please let me know if you see this mistake in print. Also let me know if you have seen these points discussed before. I learned them in my own course: talk about learning by teaching! (shrink)

This note corrects an error in my paper 'Normalisation and Subformula Property for a System of Classical Logic with Tarski's Rule' (Archive for Mathematical Logic 61 (2022): 105-129, DOI 10.1007/s00153-021-00775-6): Theorem 2 is mistaken, and so is a corollary drawn from it as well as a corollary that was concluded by the same mistake. Luckily this does not affect the main result of the paper.

We reconsider the pragmatic interpretation of intuitionistic logic [21] regarded as a logic of assertions and their justi cations and its relations with classical logic. We recall an extension of this approach to a logic dealing with assertions and obligations, related by a notion of causal implication [14, 45]. We focus on the extension to co-intuitionistic logic, seen as a logic of hypotheses [8, 9, 13] and on polarized bi-intuitionistic logic as a logic of assertions and conjectures: looking at the (...) S4 modal translation, we give a de nition of a system AHL of bi-intuitionistic logic that correctly represents the duality between intuitionistic and co-intuitionistic logic, correcting a mistake in previous work [7, 10]. A computational interpretation of cointuitionism as a distributed calculus of coroutines is then used to give an operational interpretation of subtraction.Work on linear co-intuitionism is then recalled, a linear calculus of co-intuitionistic coroutines is de ned and a probabilistic interpretation of linear co-intuitionism is given as in [9]. Also we remark that by extending the language of intuitionistic logic we can express the notion of expectation, an assertion that in all situations the truth of p is possible and that in a logic of expectations the law of double negation holds. Similarly, extending co-intuitionistic logic, we can express the notion of conjecture that p, de ned as a hypothesis that in some situation the truth of p is epistemically necessary. (shrink)

This is an attempt to axiomatise the natural laws. Note especially axiom 4, which is expressed in third order predicate logic, and which permits a solution to the problem of causation in nature without stating that “everything has a cause”. The undefined term “difference” constitutes the basic element and each difference is postulated to have an exact position and to have a discrete cause. The set of causes belonging to a natural set of dimensions is defined as a law. This (...) means that a natural law is determined by the discrete causes tied to a natural set of dimensions. A law is defined as “defined” in a point if a difference there has a cause. Given that there is a point for which the law is not defined it is shown that a difference is caused that connects two points in two separate sets of dimensions. (shrink)

There are two ways that we might respond to the underdetermination of theory by data. One response, which we can call the agnostic response, is to suspend judgment: "Where scientific standards cannot guide us, we should believe nothing". Another response, which we can call the fideist response, is to believe whatever we would like to believe: "If science cannot speak to the question, then we may believe anything without science ever contradicting us". C.S. Peirce recognized these options and suggested evading (...) the dilemma. It is a Logical Maxim, he suggests, that there could be no genuine underdetermination. This is no longer a viable option in the wake of developments in modern physics, so we must face the dilemma head on. The agnostic and fideist responses to underdetermination represent fundamentally different epistemic viewpoints. Nevertheless, the choice between them is not an unresolvable struggle between incommensurable worldviews. There are legitimate considerations tugging in each direction. Given the balance of these considerations, there should be a modest presumption of agnosticism. This may conflict with Peirce's Logical Maxim, but it preserves all that we can preserve of the Peircean motivation. (shrink)

This paper examines the evolution of Husserl’s philosophy of nonintuitive intentions. The analysis has two stages. First, I expose a mistake in Husserl’s account of non-intuitive acts from his 1901 Logical Investigations. I demonstrate that Husserl employs the term “signitive” too broadly, as he concludes that all non-intuitive acts are signitive. He states that not only meaning acts, but also the contiguity intentions of perception are signitive acts. Second, I show how Husserl, in his 1913/14 Revisions to the Sixth (...) Logical Investigation, amends his 1901 theory of non-intuitive acts, which he now calls “empty” intentions. He there accurately distinguishes empty meaning acts from the empty intentions of perception. In the conclusion, I reveal how Husserl’s alterations to his theory of non-intuitive intentions can inform our understanding of a larger shift in his philosophy. (shrink)

This paper clarifies the relationship between the Triviality Results for the conditional and the Restrictor Theory of the conditional. On the understanding of Triviality proposed here, it is implausible—pace many proponents of the Restrictor Theory—that Triviality rests on a syntactic error. As argued here, Triviality arises from simply mistaking the feature a claim has when that claim is logically unacceptable for the feature a claim has when that claim is unsatisfiable. Triviality rests on a semantic confusion—one which some semantic theories, (...) but not others, are prone to making. On the interpretation proposed here, Triviality Results thus play a theoretically constructive role in the project of natural language semantics. (shrink)

JOHN CORCORAN AND WILIAM FRANK. Surprises in logic. Bulletin of Symbolic Logic. 19 253. Some people, not just beginning students, are at first surprised to learn that the proposition “If zero is odd, then zero is not odd” is not self-contradictory. Some people are surprised to find out that there are logically equivalent false universal propositions that have no counterexamples in common, i. e., that no counterexample for one is a counterexample for the other. Some people would be surprised to (...) find out that in normal first-order logic existential import is quite common: some universals “Everything that is S is P” —actually quite a few—imply their corresponding existentials “Something that is S is P”. Anyway, perhaps contrary to its title, this paper is not a cataloging of surprises in logic but rather about the mistakes that did or might have or might still lead people to think that there are no surprises in logic. The paper cataloging of surprises in logic is on our “to-do” list. -/- ► JOHN CORCORAN AND WILIAM FRANK, Surprises in logic. Philosophy, University at Buffalo, Buffalo, NY 14260-4150, USA E-mail: [email protected] There are many surprises in logic. Peirce gave us a few. Russell gave Frege one. Löwenheim gave Zermelo one. Gödel gave some to Hilbert. Tarski gave us several. When we get a surprise, we are often delighted, puzzled, or skeptical. Sometimes we feel or say “Nice!”, “Wow, I didn’t know that!”, “Is that so?”, or the like. Every surprise belongs to someone. There are no disembodied surprises. Saying there are surprises in logic means that logicians experience surprises doing logic—not that among logical propositions some are intrinsically or objectively “surprising”. The expression “That isn’t surprising” often denigrates logical results. Logicians often aim for surprises. In fact, [1] argues that logic’s potential for surprises helps motivate its study and, indeed, helps justify logic’s existence as a discipline. Besides big surprises that change logicians’ perspectives, the logician’s daily life brings little surprises, e.g. that Gödel’s induction axiom alone implies Robinson’s axiom. Sometimes wild guesses succeed. Sometimes promising ideas fail. Perhaps one of the least surprising things about logic is that it is full of surprises. Against the above is Wittgenstein’s surprising conclusion : “Hence there can never be surprises in logic”. This paper unearths basic mistakes in [2] that might help to explain how Wittgenstein arrived at his false conclusion and why he never caught it. The mistakes include: unawareness that surprise is personal, confusing logicians having certainty with propositions having logical necessity, confusing definitions with criteria, and thinking that facts demonstrate truths. People demonstrate truths using their deductive know-how and their knowledge of facts: facts per se are epistemically inert. [1] JOHN CORCORAN, Hidden consequence and hidden independence. This Bulletin, vol.16, p. 443. [2] LUDWIG WITTGENSTEIN, Tractatus Logico-Philosophicus, Kegan Paul, London, 1921. -/-. (shrink)

This paper accomplishes three goals. First, the essay demonstrates that Edmund Husserl’s theory of meaning consciousness from his 1901 Logical Investigations is internally inconsistent and falls apart upon closer inspection. I show that Husserl, in 1901, describes non-intuitive meaning consciousness as a direct parallel or as a ‘mirror’ of intuitive consciousness. He claims that non-intuitive meaning acts, like intuitions, have substance and represent their objects. I reveal that, by defining meaning acts in this way, Husserl cannot account for our (...) experiences of countersensical, absurd, or impossible meanings. Second, I examine how Husserl came to recognize this 1901 mistake in his 1913/14 Revisions to the Sixth Logical Investigation. I discuss how he accordingly reformulates his understanding of non-intuitive meaning acts from the ground up in those Revisions, where this also allows for him to properly account for the experience of impossible meanings. Instead of describing them as mirrors of intuitions, Husserl takes non-intuitive meaning acts to be modifications of intuitions, where they have no substance and do not represent their objects. Finally, in the conclusion to this essay, I demonstrate how this fundamental change to his understanding of meaning consciousness forced Husserl to revise other central tenets of his philosophy, such that the trajectory of his thought can only be properly understood in light of these revisions to his theory of non-intuitive meaning consciousness. (shrink)

Łukasiewicz has often been criticized for his motive for inventing his three-valued logic, namely the avoidance of determinism. First of all, I want to show that almost all of the critcism along this line was wrong. Second I will indicate that he made mistakes, however, in constructing his system, because he had other motives at the same time. Finally I will propose some modification of his system and its interpretation which can attain his original purpose in some sense.

This book advertises itself as an exploration of the world-time parallel, that is, the parallel between the modal dimension, on the one hand, and the temporal dimension, on the other. It is that, and much more. As the authors point out, there is reasonable agreement that we can model times, through temporal logic, in ways that are analogous to those by which we model modality through the logic of possible worlds. But this formal parallel has almost universally been taken to (...) be a merely formal parallel: thus it is held that no metaphysical conclusions ought to be drawn from it. Thus, it is generally thought that one is free to accept an argument for actualism, say, but to reject a parallel argument for presentism. Rini and Cresswell compellingly argue that this is a mistake: the temporal and the modal are more than merely formally analogous. (shrink)

Hilbert arithmetic in a wide sense, including Hilbert arithmetic in a narrow sense consisting by two dual and anti-isometric Peano arithmetics, on the one hand, and the qubit Hilbert space (originating for the standard separable complex Hilbert space of quantum mechanics), on the other hand, allows for an arithmetic version of Gentzen’s cut elimination and quantum measurement to be described uniformy as two processes occurring accordingly in those two branches. A philosophical reflection also justifying that unity by quantum neo-Pythagoreanism links (...) it to the opposition of propositional logic, to which Gentzen’s cut rule refers immediately, on the one hand, and the linguistic and mathematical theory of metaphor therefore sharing the same structure borrowed from Hilbert arithmetic in a wide sense. An example by hermeneutical circle modeled as a dual pair of a syllogism (accomplishable also by a Turing machine) and a relevant metaphor (being a formal and logical mistake and thus fundamentally inaccessible to any Turing machine) visualizes human understanding corresponding also to Gentzen’s cut elimination and the Gödel dichotomy about the relation of arithmetic to set theory: either incompleteness or contradiction. The metaphor as the complementing “half” of any understanding of hermeneutical circle is what allows for that Gödel-like incompleteness to be overcome in human thought. (shrink)

Contemporary discourse is littered with nasty and derailed disagreements. In this paper we hope to help clean things up. We diagnose two patterns of thought that often plague and exacerbate controversy. We illustrate these patterns and show that each involves both a logical mistake and a failure of intellectual charity. We also draw upon recent work in social psychology to shed light on why we tend to fall into these patterns of thought. We conclude by suggesting how the intellectual (...) virtues can militate against these fallacies, focusing on the virtues of charity and humility. (shrink)

The aim of this paper was to prove that reduction of social, cultural and spiritual explanation of religion, to the purely biological one, is unattainable, and what is more, that such efforts are redundant and give threat to the quality of science, as well as to the quality of religious beliefs. With regard to elementary methodological scientific criteria, the examples of limitation in biological investigating and explaining of religion was shown. Subsequently, the paper presents a few important logical (...) class='Hi'>mistakes (pseudoarguments) as examples of ontological underinterpretation of scientific facts. Finally, the discourse concentrates on the threats (to science and religion) that are associated with biological investigation of religion. (shrink)

In Tractatus 5.132 Wittgenstein argues that inferential justification depends solely on the understanding of the premises and conclusion, and is not mediated by any further act. On this basis he argues that Frege’s and Russell’s rules of inference are “senseless” and “superfluous”. This line of argument is puzzling, since it is unclear that there could be any viable account of inference according to which no such mediation takes place. I show that Wittgenstein’s rejection of rules of inference can be motivated (...) by taking account of his holistic construal of the relation between inference and understanding. (shrink)

Description logics and other formal devices are frequently used as means for preventing or detecting mistakes in ontologies. Some of these devices are also capable of inferring the existence of inter-concept relationships that have not been explicitly entered into an ontology. A prerequisite, however, is that this information can be derived from those formal definitions of concepts and relationships which are included within the ontology. In this paper, we present a novel algorithm that is able to suggest relationships among (...) existing concepts in a formal ontology that are not derivable from such formal definitions. The algorithm exploits cross-lingual information that is implicitly present in the collection of terms used in various languages to denote the concepts and relationships at issue. By using a specific experimental design, we are able to quantify the impact of cross-lingual information in coping with underspecification in formal ontologies. (shrink)

In this paper, I offer a close reading of Wittgenstein's remarks on inconsistency, mostly as they appear in the Lectures on the Foundations of Mathematics. I focus especially on an objection to Wittgenstein's view given by Alan Turing, who attended the lectures, the so-called ‘falling bridges’-objection. Wittgenstein's position is that if contradictions arise in some practice of language, they are not necessarily fatal to that practice nor necessitate a revision of that practice. If we then assume that we have adopted (...) a paraconsistent logic, Wittgenstein's answer to Turing is that if we run into trouble building our bridge, it is either because we have made a calculation mistake or our calculus does not actually describe the phenomenon it is intended to model. The possibility of either kind of error is not particular to contradictions nor inconsistency, and thus contradictions do not have any special status as a thing to be avoided. (shrink)

I argue that No-Ought-From-Is (in the sense that I believe it) is a relatively trivial affair. Of course, when people try to derive substantive or non-vacuous moral conclusions from non-moral premises, they are making a mistake. But No-Non-Vacuous-Ought-From-Is is meta-ethically inert. It tells us nothing about the nature of the moral concepts. It neither refutes naturalism nor supports non-cognitivism. And this is not very surprising since it is merely an instance of an updated version of the conservativeness of logic (in (...) a logically valid inference you don’t get out what you haven’t put in): so long as the expressions F are non-logical, you cannot get non-vacuous F-conclusions from non-F premises. However, the triviality of No-Non-Vacuous-Ought-From-Is is important and its non-profundity profound. No-Ought-From-Is is widely supposed to tell us something significant about the nature of the moral concepts. If, in fact, it tells us nothing, this is a point well worth shouting from the housetops. This brings me to my dispute with Gerhard Schurz who has proved a related version of No-Ought-From-Is, No-Ought-Relevant-Ought-From-Is, a proof which relaxes my assumption that ‘ought’ should not be treated as a logical constant. But if ought is not a logical expression then it does not really matter much that No-Ought-From-Is would be salvageable even if it were. Furthermore, Schurz’s proof depends on special features of the moral concepts and this might afford the basis for an abductive argument to something like non-cognitivism. As an error theorist, and therefore a cognitivist, I object. Finally I take a dim view of deontic logic. Many of its leading principles are false, bordering on the nonsensical, and even the reasonably plausible ones are subject to devastating counter-examples. (shrink)

The literature on material composition has largely ignored the composition of actions and events. I argue that this is a mistake. I present a set of individually plausible yet jointly inconsistent claims regarding the connection between quantification and existence, the composition of physical entities and the logical forms of action sentences.

Girolamo Saccheri (1667--1733) was an Italian Jesuit priest, scholastic philosopher, and mathematician. He earned a permanent place in the history of mathematics by discovering and rigorously deducing an elaborate chain of consequences of an axiom-set for what is now known as hyperbolic (or Lobachevskian) plane geometry. Reviewer's remarks: (1) On two pages of this book Saccheri refers to his previous and equally original book Logica demonstrativa (Turin, 1697) to which 14 of the 16 pages of the editor's "Introduction" are devoted. (...) At the time of the first edition, 1920, the editor was apparently not acquainted with the secondary literature on Logica demonstrativa which continued to grow in the period preceding the second edition \ref[see D. J. Struik, in Dictionary of scientific biography, Vol. 12, 55--57, Scribner's, New York, 1975]. Of special interest in this connection is a series of three articles by A. F. Emch [Scripta Math. 3 (1935), 51--60; Zbl 10, 386; ibid. 3 (1935), 143--152; Zbl 11, 193; ibid. 3 (1935), 221--333; Zbl 12, 98]. (2) It seems curious that modern writers believe that demonstration of the "nondeducibility" of the parallel postulate vindicates Euclid whereas at first Saccheri seems to have thought that demonstration of its "deducibility" is what would vindicate Euclid. Saccheri is perfectly clear in his commitment to the ancient (and now discredited) view that it is wrong to take as an "axiom" a proposition which is not a "primal verity", which is not "known through itself". So it would seem that Saccheri should think that he was convicting Euclid of error by deducing the parallel postulate. The resolution of this confusion is that Saccheri thought that he had proved, not merely that the parallel postulate was true, but that it was a "primal verity" and, thus, that Euclid was correct in taking it as an "axiom". As implausible as this claim about Saccheri may seem, the passage on p. 237, lines 3--15, seems to admit of no other interpretation. Indeed, Emch takes it this way. (3) As has been noted by many others, Saccheri was fascinated, if not obsessed, by what may be called "reflexive indirect deductions", indirect deductions which show that a conclusion follows from given premises by a chain of reasoning beginning with the given premises augmented by the denial of the desired conclusion and ending with the conclusion itself. It is obvious, of course, that this is simply a species of ordinary indirect deduction; a conclusion follows from given premises if a contradiction is deducible from those given premises augmented by the denial of the conclusion---and it is immaterial whether the contradiction involves one of the premises, the denial of the conclusion, or even, as often happens, intermediate propositions distinct from the given premises and the denial of the conclusion. Saccheri seemed to think that a proposition proved in this way was deduced from its own denial and, thus, that its denial was self-contradictory (p. 207). Inference from this mistake to the idea that propositions proved in this way are "primal verities" would involve yet another confusion. The reviewer gratefully acknowledges extensive communication with his former doctoral students J. Gasser and M. Scanlan. ADDED 14 March 14, 2015: (1) Wikipedia reports that many of Saccheri's ideas have a precedent in the 11th Century Persian polymath Omar Khayyám's Discussion of Difficulties in Euclid, a fact ignored in most Western sources until recently. It is unclear whether Saccheri had access to this work in translation, or developed his ideas independently. (2) This book is another exemplification of the huge difference between indirect deduction and indirect reduction. Indirect deduction requires making an assumption that is inconsistent with the premises previously adopted. This means that the reasoner must perform a certain mental act of assuming a certain proposition. It case the premises are all known truths, indirect deduction—which would then be indirect proof—requires the reasoner to assume a falsehood. This fact has been noted by several prominent mathematicians including Hardy, Hilbert, and Tarski. Indirect reduction requires no new assumption. Indirect reduction is simply a transformation of an argument in one form into another argument in a different form. In an indirect reduction one proposition in the old premise set is replaced by the contradictory opposite of the old conclusion and the new conclusion becomes the contradictory opposite of the replaced premise. Roughly and schematically, P,Q/R becomes P,~R/~Q or ~R, Q/~P. Saccheri’s work involved indirect deduction not indirect reduction. (3) The distinction between indirect deduction and indirect reduction has largely slipped through the cracks, the cracks between medieval-oriented logic and modern-oriented logic. The medievalists have a heavy investment in reduction and, though they have heard of deduction, they think that deduction is a form of reduction, or vice versa, or in some cases they think that the word ‘deduction’ is the modern way of referring to reduction. The modernists have no interest in reduction, i.e. in the process of transforming one argument into another having exactly the same number of premises. Modern logicians, like Aristotle, are concerned with deducing a single proposition from a set of propositions. Some focus on deducing a single proposition from the null set—something difficult to relate to reduction. (shrink)

►JOHN CORCORAN AND IDRIS SAMAWI HAMID, Two-method errors: having it both ways. Philosophy, University at Buffalo, Buffalo, NY 14260-4150, USA E-mail: [email protected] Philosophy, Colorado State University, Fort Collins, CO 80523-1781 USA E-mail: [email protected] Where two methods produce similar results, mixing the two sometimes creates errors we call two-method errors, TMEs: in style, syntax, semantics, pragmatics, implicature, logic, or action. This lecture analyzes examples found in technical and in non-technical contexts. One can say “Abe knows whether Ben draws” in two other (...) ways: ‘Abe knows whether or not Ben draws’ or ‘Abe knows whether Ben draws or not’. But a stylistic TME occurs in ‘Abe knows whether or not Ben draws or not’. One can say “Abe knows how Ben looks” using ‘Abe knows what Ben looks like’. But syntactical TMEs are in ‘Abe knows what Ben looks’ and in ‘Abe knows how Ben looks like’. One can deny that Abe knows Ben by prefixing ‘It isn’t that’ or by interpolating ‘doesn’t’. But a pragmatic TME occurs in trying to deny that Abe knows Ben by using ‘It isn’t that Abe doesn’t know Ben’. There are several standard ways of defining truth using sequences. Quine’s discussions in the 1970 first printing of Philosophy of logic [3] and in previous lectures were vitiated by mixing two [1, p. 98]. The logical TME in [3], which eluded Quine’s colleagues, was corrected in the 1978 sixth printing [2]. But Quine never explicitly acknowledged, described, or even mentioned the error. This lecture presents and analyses two-method errors in the logic literature. [1] JOHN CORCORAN, Review of Quine’s 1970 Philosophy of Logic. In Philosophy of Science, vol. 39 (1972), pp. 97–99. [2] JOHN CORCORAN, Review of sixth printing of Quine’s 1970 Philosophy of Logic. In Mathematical Reviews MR0469684 (1979): 57 #9465. [3] WILLARD VAN ORMAN QUINE, Philosophy of logic, Harvard, 1970/1986. (shrink)

The development of a book is an enjoyable task. Whatever the contents of this book might be, I assure you that I would try my best to put things in such a simple language in an easy-to-understand manner. Moreover, I also promise to be as blunt and frank as I could be. -/- I have been thinking of writing this book for quite some time; however, I have decided if I am going to write one book, then I might as (...) well write more books since I am going over the basics of some of my thoughts and theories in this very first book.6 However, my thoughts and theories are the least important since everybody could be wrong, and my thoughts could have been the same as others. -/- Yet, as mentioned earlier, these are only the base of my thoughts, observations, and theories and do not include all the subjects I would love to share. I have written in this very first book a brief introduction to some of my thoughts. -/- Furthermore, they are nothing special since we all think we have something special to say. I might perhaps be under the same impression as everybody else. -/- Also, I have to admit that I am an average person like any other person who could make mistakes. Therefore, I see myself entitled to change of opinion if better logic is provided sufficiently. -/- I have to try writing this book since it is already long overdue, and it is time to share my opinions and7 understandings of the world as simple and as naive that they can be! -/- Moreover, this book will be as I usually say that ''in school, first, you learn a lesson then you have a test, but in life, first, you have a test then you learn a lesson''. -/- So I promise to listen to your criticism and pieces of advice to make myself better and develop into a better and wiser individual. I hope this book helps us both. -/- This book is not about me being right or wrong since I will always look forward to criticism since critics are the ones that help us be better at what we are or what we are trying to accomplish. (shrink)

Closure for justification is the claim that thinkers are justified in believing the logical consequences of their justified beliefs, at least when those consequences are competently deduced. Many have found this principle to be very plausible. Even more attractive is the special case of Closure known as Single-Premise Closure. In this paper, I present a challenge to Single-Premise Closure. The challenge is based on the phenomenon of rational self-doubt – it can be rational to be less than fully confident (...) in one's beliefs and patterns of reasoning. In rough outline, the argument is as follows: Consider a thinker who deduces a conclusion from a justified initial premise via an incredibly long sequence of small competent deductions. Surely, such a thinker should suspect that he has made a mistake somewhere. And surely, given this, he should not believe the conclusion of the deduction even though he has a justified belief in the initial premise. (shrink)

One of the singularities of Latin exegesis of Aristotle’s Sophistici elenchi, is that it arbitrarily brought together two families of fallacies, the «figure of speech» and the «accident», despite the fact that they are on either side of the divide between sophisms related to expression and sophisms independent of expression, a divide that lays at the heart of Aristotle’s taxonomy of sophistic arguments. What is behind this surprising identification? The talk is meant to show that it actually originates from a (...) curious mistake in Boethius’ translation of Aristotle’s Sophistici elenchi, 22, 178b 36-37 which radically transformed the nature of the argument at stake. While it was originally an example of the fallacies related to the «figure of speech», Boethius’ translation wrongly brings about two arguments instead of one, both related to the «accident». This explains why authors from the Latin tradition came to think that fallacies of «figure of speech» were linked to fallacies of «accident» closely enough to ask whether they actually fell outside expression, even though it does not at first glance appear that such a possibility was allowed or even suggested by Aristotle’s text. This odd question illustrates some of the remarkable features of the medieval archive and how some of its most peculiar problems came to be. It specifically allows us to reconstruct the mechanisms through which a minor disturbance in the letter of the text leads to a whole new way of organising its exegetical material. (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.

Quality assurance in large terminologies is a difficult issue. We present two algorithms that can help terminology developers and users to identify potential mistakes. We demon­strate the methodology by outlining the different types of mistakes that are found when the algorithms are applied to SNOMED-CT. On the basis of the results, we argue that both formal logical and linguistic tools should be used in the development and quality-assurance process of large terminologies.

Clare Batty has recently argued that the content of human olfactory experience is 'a very weak kind of abstract, or existentially quantified content', and so that 'there is no way things smell'. Her arguments are based on two claims. Firstly, that there is no intuitive distinction between olfactory hallucination and olfactory illusion. Secondly, that olfaction 'does not present smell at particular locations', and 'seems disengaged from any particular object'. The present article shows both of these claims to be false. It (...) shows that naïve subjects find it quite natural to draw a distinction between olfactory hallucination and olfactory illusion. And it argues that the phenomenology of normal olfactory experience is of particular objects as having smells. Two confusions are responsible for Batty thinking otherwise: (1) Batty's examples are cases of extreme pungency, and she mistakes a peculiarity of intense perceptions for a property of olfaction more generally; (2) Batty focuses on very short time slices and so confuses limitations on the information carried by a single sniff for a limitation on the logical form of all olfactory content. (shrink)

A sorites argument is a symptom of the vagueness of the predicate with which it is constructed. A vague predicate admits of at least one dimension of variation (and typically more than one) in its intended range along which we are at a loss when to say the predicate ceases to apply, though we start out confident that it does. It is this feature of them that the sorites arguments exploit. Exactly how is part of the subject of this paper. (...) The majority of philosophers writing on vagueness take it to be a kind of semantic phenomenon. If we are right, they are correct in this assumption, which is surely the default position, but they have not so far provided a satisfactory account of the implications of this or a satisfactory diagnosis of the sorites arguments. Other philosophers have urged more exotic responses, which range from the view that the fault lies not in our language, but in the world, which they propose to be populated with vague objects which our semantics precisely reflects, to the view that the world and language are both perfectly in order, but that the fault lies with our knowledge of the properties of the words we use (epistemicism). In contrast to the exotica to which some philosophers have found themselves driven in an attempt to respond to the sorites puzzles, we undertake a defense of the commonsense view that vague terms are semantically vague. Our strategy is to take fresh look at the phenomenon of vagueness. Rather than attempting to adjudicate between different extant theories, we begin with certain pre-theoretic intuitions about vague terms, and a default position on classical logic. The aim is to see whether (i) a natural story can be told which will explain the vagueness phenomenon and the puzzling nature of soritical arguments, and, in the course of this, to see whether (ii) there arises any compelling pressure to give up the natural stance. We conclude that there is a simple and natural story to be told, and we tell it, and that there is no good reason to abandon our intuitively compelling starting point. The importance of the strategy lies in its dialectical structure. Not all positions on vagueness are on a par. Some are so incredible that even their defenders think of them as positions of last resort, positions to which we must be driven by the power of philosophical argument. We aim to show that there is no pressure to adopt these incredible positions, obviating the need to respond to them directly. If we are right, semantic vagueness is neither surprising, nor threatening. It provides no reason to suppose that the logic of natural languages is not classical or to give up any independently plausible principle of bivalence. Properly understood, it provides us with a satisfying diagnosis of the sorites argumentation. It would be rash to claim to have any completely novel view about a topic so well worked as vagueness. But we believe that the subject, though ancient, still retains its power to inform and challenge us. In particular, we will argue that taking seriously the central phenomenon of predicate vagueness—the “boundarylessness” of vague predicates—on the commonsense assumption that vagueness is semantic, leads ineluctably to the view that no sentences containing vague expressions (henceforth ‘vague sentences’) are truth-evaluable. This runs counter to much of the literature on vagueness, which commonly assumes that, though some applications of vague predicates to objects fail to be truth-evaluable, in clear positive and negative cases vague sentences are unproblematically true or false. It is clarity on this, and related points, that removes the puzzles associated with vagueness, and helps us to a satisfying diagnosis of why the sorites arguments both seem compelling and yet so obviously a bit of trickery. We give a proof that semantically vague predicates neither apply nor fail-to-apply to anything, and that consequently it is a mistake to diagnose sorites arguments, as is commonly done, by attempting to locate in them a false premise. Sorites arguments are not sound, but not unsound either. We offer an explanation of their appeal, and defend our position against a variety of worries that might arise about it. The plan of the paper is as follows. We first introduce an important distinction in terms of which we characterize what has gone wrong with vague predicates. We characterize what we believe to be our natural starting point in thinking about the phenomenon of vagueness, from which only a powerful argument should move us, and then trace out the consequences of accepting this starting point. We consider the charge that among the consequences of semantic vagueness are that we must give up classical logic and the principle of bivalence, which has figured prominently in arguments for epistemicism. We argue there are no such consequences of our view: neither the view that the logic of natural languages is classical, nor any plausible principle of bivalence, need be given up. Next, we offer a diagnosis of what has gone wrong in sorites arguments on the basis of our account. We then present an argument to show that our account must be accepted on pain of embracing (in one way or another) the epistemic view of “vagueness”, i.e., of denying that there are any semantically vague terms at all. Next, we discuss some worries that may arise about the intelligibility of our linguistic practices if our account is correct. We argue none of these worries should force us from our intuitive starting point. Finally, we cast a quick glance at other forms of semantic incompleteness. (shrink)

In reflecting on the relation between early empiricist conceptions of the mind and more experimentally motivated materialist philosophies of mind in the mid-eighteenth century, I suggest that we take seriously the existence of what I shall call ‘phantom philosophical projects’. A canonical empiricist like Locke goes out of his way to state that their project to investigate and articulate the ‘logic of ideas’ is not a scientific project: “I shall not at present meddle with the Physical consideration of the Mind” (...) (Essay, I.i.2). An equally prominent thinker, Immanuel Kant, seems to make an elementary mistake, given such a clear statement, when he claims that Locke’s project was a “physiology of the understanding,” in the Preface to the A edition of the first Critique). A first question, then, would be: what is this physiology of the understanding, if it was not Locke’s project? Did anyone undertake such a project? If not, what would it have resembled? My second and related case comes out of a remark the Hieronymus Gaub makes in a letter to Charles Bonnet of 1761: criticizing materialist accounts of mind and mind-body relations such as La Mettrie’s, Gaub suggests that what is needed is a thorough study of the “mechanics of the soul,” and that Bonnet could write such a study. What is the mechanics of the soul, especially given that it is presented as a non-materialist project? To what extent does it resemble the purported “physiology of the understanding”? And more generally, what do both of these phantom projects have to do with a process we might describe as a ‘naturalization of the soul’? (shrink)

In his famous work on vagueness, Russell named “fallacy of verbalism” the fallacy that consists in mistaking the properties of words for the properties of things. In this paper, I examine two (clusters of) mainstream paraconsistent logical theories – the non-adjunctive and relevant approaches –, and show that, if they are given a strongly paraconsistent or dialetheic reading, the charge of committing the Russellian Fallacy can be raised against them in a sophisticated way, by appealing to the intuitive reading (...) of their underlying semantics. The meaning of “intuitive reading” is clarified by exploiting a well-established distinction between pure and applied semantics. If the proposed arguments go through, the dialetheist or strong paraconsistentist faces the following Dilemma: either she must withdraw her claim to have exhibited true contradictions in a metaphysically robust sense – therefore, inconsistent objects and/or states of affairs that make those contradictions true; or she has to give up realism on truth, and embrace some form of anti-realistic (idealistic, or broadly constructivist) metaphysics. Sticking to the second horn of the Dilemma, though, appears to be promising: it could lead to a collapse of the very distinction, commonly held in the literature, between a weak and a strong form of paraconsistency – and this could be a welcome result for a dialetheist. (shrink)

The issue of whether or not there are visual arguments has been an issue in informal logic and argumentation theory at least since 1996. In recent years, books, sections of prominent conferences and special journals issues have been devoted to it, thus significantly raising the profile of the debate. In this paper I will attempt to show how the views of the later Wittgenstein, particularly his views on images and the no- tion of “picturing”, can be brought to bear on (...) the question of whether there are such things as “purely visual” arguments. I shall draw on Wittgenstein’s remarks in the Blue and Brown Books and in Philosophical Investigations in order to argue that al- though visual images may occur as elements of argumentation, broadly conceived, it is a mistake to think that there are purely visual arguments, in the sense of illative moves from premises to conclusions that are conveyed by images alone, without the support or framing of words. (shrink)

This paper could be thought of as divided into two parts. In the first I show through a series of thought experiments that it is a mistake to think of one’s individual experience as necessarily belonging to only one particular place, time and organism. In repetitions across a universe large enough to host them, the particular experience that one finds oneself in, which can be individuated only by the detailed type that is the entirety of its momentary subjective content, would (...) exist equally in every occurrence of that type, much as a moment in the plot of a novel would exist equally in every copy of that novel. Each distinguishable subjective moment of experience is thus a ‘moment universal’. In the second part of the paper I draw from this the conclusion that there could not be any proper possessors of lines of experience - that there are no proper persons - no continuing subjects of consciousness and self-interest. About five years after writing this paper I came to see that the particular identity of an experience could not be confined by types of momentary subjective detail any more than it could be confined by particular places, times or organisms. All experience is equally here, now and mine and all conscious organisms are equally I. My argument for this crucial further development is presented in ‘One Self – The Logic of Experience’, Inquiry 33 (1991): pp. 39-68. (shrink)

Misrecognition from other individuals and social institutions is by its dynamic or ‘logic’ such that it can lead to distorted relations-to-self, such as self-hatred, and can truncate the development of the central capabilities of persons. Thus it is worth trying to shed light on how mis recognition differs from adequate recognition, and on how mis recognition might differ from other kinds of mistreatment and disregard. This paper suggests that mis recognition (including nonrecognition) is a matter of inadequate responsiveness to the (...) normatively relevant features of someone (their personhood, merits, needs etc.), and that if the kind of mistreatment in question obeys the general dynamic or ‘logic’ of mutual recognition and relations-to-self, then it may be called ‘misrecognition’. Further, this article considers the multiple connections between misrecognition and human fallibility. The capacity to get things wrong or make mistakes (that is, fallibility) is first of all a condition of misrecognition. Furthermore, there are two lessons that we can draw from fallibility. The first one points towards minimal objectivism: if something is to count as a mistake or incorrect response, there must accordingly exist a fact of the matter or a correct response. The other lesson points towards public equality: if our capacity to get things right on our own is limited, then public, shared norms will probably help. Such norms are easier to know and follow than objective normative truths, and they may contain collective cumulative wisdom; and of course the process of creating public norms embodies in itself an important form of mutual recognition between citizens. (shrink)

The austere view of nonsense says that the source of nonsense is not a violation of the rules of logical syntax, but nonsense is always due to a lack of meaning in one of the components of a sentence. In other words, the necessary and sufficient condition for nonsensicality is that no meaning has been assigned to a constituent in a sentence. The austere conception is the key ingredient of the resolute reading of Tractatus Logico-Philosophicus that presents a therapeutical (...) interpretation of the work, and rejects a possibility of conveying some ineffable truths by means of nonsensical sentences. In this paper, I defend the austere view against the most important objections. Firstly, I discuss textual sources for ascribing to Wittgenstein the austere view that have not been sufficiently thoroughly discussed yet. Next, I indicate that the apparent occurrence of words out of the context of a sentence on lists of verbs and in definitions is not in conflict with the version of the context principle recommended by austere theorists, since this argument does not sufficiently take into account the distinction between sign and symbol. Furthermore, I argue that the austere conception and the principle of compositionality are jointly tenable, for the former view does not exclude the existence of syntactic and semantic rules, but only shows that they are recognizable conditionally. Finally, I indicate that the austere view of nonsense should be seen as a viable option by a contemporary theorist of nonsense, for it helps us to avoid making controversial assumptions about the nature of meaning and content. (shrink)

This chapter argues that adequately facing and responding to medical error requires making space for blame. In vindicating blame as a response to medical error, this essay does not advocate a return to a “bad apple” blame culture in which unlucky practitioners are unfairly scapegoated. It does, however, defend the targeted feeling and expression of angry, and even resentful, blaming attitudes toward health-care providers who make at least certain kinds of mistakes. The chapter makes the case that the angry (...) and resentful feelings associated with blame reflect a conception of oneself as a person worthy of consideration, and that expressing these feelings allows victims and families to fight for their dignity and self-respect. Along the way, it distinguishes between shaming and blaming, explaining that blaming, unlike shaming, characteristically aims to draw offenders into a moral dialogue. As a result, a good blaming practice can provide a logic within which providers who make costly errors may seek forgiveness, reconciliation, and healing. (shrink)

Deductive reasoning is the kind of reasoning in which, roughly, the truth of the input propositions (the premises) logically guarantees the truth of the output proposition (the conclusion), provided that no mistake has been made in the reasoning. The premises may be propositions that the reasoner believes or assumptions that the reasoner is exploring. Deductive reasoning contrasts with inductive reasoning, the kind of reasoning in which the truth of the premises need not guarantee the truth of the conclusion.

John von Neumann's proof that quantum mechanics is logically incompatible with hidden varibales has been the object of extensive study both by physicists and by historians. The latter have concentrated mainly on the way the proof was interpreted, accepted and rejected between 1932, when it was published, and 1966, when J.S. Bell published the first explicit identification of the mistake it involved. What is proposed in this paper is an investigation into the origins of the proof rather than the aftermath. (...) In the first section, a brief overview of the his personal life and his proof is given to set the scene. There follows a discussion on the merits of using here the historical method employed elsewhere by Andrew Warwick. It will be argued that a study of the origins of von Neumann's proof shows how there is an interaction between the following factors: the broad issues within a specific culture, the learning process of the theoretical physicist concerned, and the conceptual techniques available. In our case, the ‘conceptual technology’ employed by von Neumann is identified as the method of axiomatisation. (shrink)

Modern semiotics is a branch of logics that formally defines symbol-based communication. In recent years, the semiotic classification of signs has been invoked to support the notion that symbols are uniquely human. Here we show that alarm-calls such as those used by African vervet monkeys (Cercopithecus aethiops), logically satisfy the semiotic definition of symbol. We also show that the acquisition of vocal symbols in vervet monkeys can be successfully simulated by a computer program based on minimal semiotic and neurobiological constraints. (...) The simulations indicate that learning depends on the tutor-predator ratio, and that apprentice-generated auditory mistakes in vocal symbol interpretation have little effect on the learning rates of apprentices (up to 80% of mistakes are tolerated). In contrast, just 10% of apprentice-generated visual mistakes in predator identification will prevent any vocal symbol to be correctly associated with a predator call in a stable manner. Tutor unreliability was also deleterious to vocal symbol learning: a mere 5% of “lying” tutors were able to completely disrupt symbol learning, invariably leading to the acquisition of incorrect associations by apprentices. Our investigation corroborates the existence of vocal symbols in a non-human species, and indicates that symbolic competence emerges spontaneously from classical associative learning mechanisms when the conditioned stimuli are self-generated, arbitrary and socially efficacious. We propose that more exclusive properties of human language, such as syntax, may derive from the evolution of higher-order domains for neural association, more removed from both the sensory input and the motor output, able to support the gradual complexification of grammatical categories into syntax. (shrink)

Starting from the premise that akrasia is irrational, I argue that it is always a rational mistake to have false beliefs about the requirements of rationality. Using that conclusion, I defend logical omniscience requirements, the claim that one can never have all-things-considered misleading evidence about what's rational, and the Right Reasons position concerning peer disagreement.

How does Locke contribute to the development of 18th-century projects for a science of the mind, even though he seems to reject or at least bracket off such an idea himself? Contrary to later understandings of empiricism, Locke goes out of his way to state that his project to investigate and articulate the ‘logic of ideas’ is not a scientific project: “I shall not at present meddle with the Physical consideration of the Mind” (Essay, I.i.2). Locke further specifies that this (...) means his analysis of mental processes will not engage with knowledge of the brain (e.g. in terms of corpuscles and animal spirits), even though he had been the student of Thomas Willis. Now, Kant seemed to make an elementary mistake, given such a clear statement on Locke’s part, when he claimed that Locke’s project was a “physiology of the understanding” (in the Preface to the A edition of the first Critique). One can ask of course what this physiology of the understanding was, and if it existed, in or out of the Lockean intellectual world (as I have sought to investigate in a 2016 paper). This leads me to inquire into the outcome of his empiricism for a scientific treatment of the mind, including in the sense of a ‘naturalization’ of the mind (with implications also for our understanding of empiricism: Anstey’s influential distinction between experimental and speculative philosophy does not seem useful here). Because if Kant made this charge, there were also many 18th-century thinkers who positively treated Locke as their great forerunner in psychology and related fields: Charles Bonnet and Joseph Priestley among them, just as some prominent physicians such as Cabanis claimed to be ‘finishing the job’ that Locke had started in, e.g. their materialist theories of the passions. What one might term ‘the Locke Problem’ here is: how can one reconcile empiricism and claims about cerebral processes, while seeking to remain a Lockean? Differently put, what is the process of naturalization, a naturalization of? (shrink)