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)

The holism-reductionism debate, one of the classic subjects of study in the philosopy of science, is currently at the heart of epistemological concerns in ecology. Yet the division between holism and reductionism does not always stand out clearly in this field. In particular, almost all work in ecosystem ecology and landscape ecology presents itself as holistic and emergentist. Nonetheless, the operational approaches used rely on conventional reductionist methodology.From an emergentist epistemological perspective, a set of general 'transactional' principles inspired by the (...) work of J. Dewey and J.K. Feibleman are proposed in an effort to develop a coherent ontological and methodological semantics. (shrink)

This paper examines a paradigm case of allegedly successful reductive explanation, viz. the explanation of the fact that water boils at 100°C based on facts about H2O. The case figures prominently in Joseph Levine’s explanatory gap argument against physicalism. The paper studies the way the argument evolved in the writings of Levine, focusing especially on the question how the reductive explanation of boiling water figures in the argument. It will turn out that there are two versions of the explanatory gap (...) argument to be found in Levine’s writings. The earlier version relies heavily on conceptual analysis and construes reductive explanation as a process of deduction. The later version makes do without conceptual analysis and understands reductive explanations as based on theoretic reductions that are justified by explanatory power. Along the way will be shown that the bridge principles — which are being neglected in the explanatory gap literature — play a crucial role in the explanatory gap argument. (shrink)

Emergence is much discussed by both philosophers and scientists. But, as noted by Mitchell (2012), there is a significant gulf; philosophers and scientists talk past each other. We contend that this is because philosophers and scientists typically mean different things by emergence, leading us to distinguish being emergence and pattern emergence. While related to distinctions offered by others between, for example, strong/weak emergence or epistemic/ontological emergence (Clayton, 2004, pp. 9–11), we argue that the being vs. pattern distinction better captures what (...) the two groups are addressing. In identifying pattern emergence as the central concern of scientists, however, we do not mean that pattern emergence is of no interest to philosophers. Rather, we argue that philosophers should attend to, and even contribute to, discussions of pattern emergence. But it is important that this discussion be distinguished, not conflated, with discussions of being emergence. In the following section we explicate the notion of being emergence and show how it has been the focus of many philosophical discussions, historical and contemporary. In section 3 we turn to pattern emergence, briefly presenting a few of the ways it figures in the discussions of scientists (and philosophers of science who contribute to these discussions in science). Finally, in sections 4 and 5, we consider the relevance of pattern emergence to several central topics in philosophy of biology: the emergence of complexity, of control, and of goal-directedness in biological systems. (shrink)

This chapter defends Terence Horgan's claim that any genuinely physicalist position must distinguish itself from (what has been traditionally known as) emergentism. It argues that physicalism is necessarily reductive in character — it must either give a reductive account of apparently non‐physical entities, or a reductive explanation of why there are non‐physical entities. It contends that many recent ‘non‐reductive’ physicalists do not do this, and that because of this they cannot adequately distinguish their view from emergentism. The conclusion is that (...) this is the real challenge posed by Joseph Levine's ‘explanatory gap’ argument: if physicalists cannot close the explanatory gap in Levine's preferred way, they must find some other way to do it. Otherwise their view is indistinguishable from emergentism. (shrink)

The purpose of this Perspective Essay was to logically examine and rebut some of the common arguments posited by Atheists against the existence of God. The essay is purely philosophical. The critical tool of discourse is Deductive argumentation. The essay infers that appealing to the existence of evil as proof against God's existence is a weak argument based on a faulty conception of the term ‘evil'. It also deduces that what an Atheist calls biblical contradictions are not in the strictest (...) sense contradictions. Lastly, the argument that God's existence is impossible due to the immorality of those who believe in God is not tenable because God's existence and his nature do not include human conduct. (shrink)

Schaffner’s model of theory reduction has played an important role in philosophy of science and philosophy of biology. Here, the model is found to be problematic because of an internal tension. Indeed, standard antireductionist external criticisms concerning reduction functions and laws in biology do not provide a full picture of the limits of Schaffner’s model. However, despite the internal tension, his model usefully highlights the importance of regulative ideals associated with the search for derivational, and embedding, deductive relations (...) among mathematical structures in theoretical biology. A reconstructed Schaffnerian model could therefore shed light on mathematical theory development in the biological sciences and on the epistemology of mathematical practices more generally. *Received November 2006; revised March 2009. †To contact the author, please write to: Philosophy Department, University of California, Santa Cruz, 1156 High St., Santa Cruz, CA 95064; e‐mail: [email protected]. (shrink)

This paper reveals errors within Norwich et al.’s Entropy Theory of Perception, errors that have broad implications for our understanding of perception. What Norwich and coauthors dubbed their “informational theory of neural coding” is based on cybernetics, that is, control and communication in man and machine. The Entropy Theory uses information theory to interpret human performance in absolute judgments. There, the continuum of the intensity of a sensory stimulus is cut into categories and the subject is shown exemplar stimuli of (...) each category. The subject must then identify individual exemplars by category. The identifications are recorded in the Garner-Hake version of the Shannon “confusion matrix”. The matrix yields “H”, the entropy (degree of uncertainty) about what stimulus was presented. Hypothetically, uncertainty drops as a stimulus lengthens, i.e. a plot of H vs. stimulus duration should fall monotonically. Such “adaptation” is known for both sensation and firing rate. Hence, because “the physiological adaptation curve has the same general shape as the psychophysical adaptation curve”, Norwich et al. assumed that both have the same time course; sensation and firing rate were thus both declared proportional to H. However, a closer look reveals insurmountable contradictions. First, the peripheral neuron hypothetically cannot fire in response to a stimulus of a given intensity until after somehow computing H from its responses to stimuli of various intensities. Thus no sensation occurs until firing rate adapts, i.e. attains its spontaneous rate. But hypothetically, once adaptation is complete, certainty is reached and perception ends. Altogether, then, perception cannot occur until perception is over. Secondly, sensations, firing rates, and H’s are empirically not synchronous, contrary to assumption. In sum, the core concept of the cybernetics-based Entropy Theory of Perception, that is, that uncertainty reduction is the basis for perception, is irrational. (shrink)

The Logic of Causation: Definition, Induction and Deduction of Deterministic Causality is a treatise of formal logic and of aetiology. It is an original and wide-ranging investigation of the definition of causation (deterministic causality) in all its forms, and of the deduction and induction of such forms. The work was carried out in three phases over a dozen years (1998-2010), each phase introducing more sophisticated methods than the previous to solve outstanding problems. This study was intended as part (...) of a larger work on causal logic, which additionally treats volition and allied cause-effect relations (2004). The Logic of Causation deals with the main technicalities relating to reasoning about causation. Once all the deductive characteristics of causation in all its forms have been treated, and we have gained an understanding as to how it is induced, we are able to discuss more intelligently its epistemological and ontological status. In this context, past theories of causation are reviewed and evaluated (although some of the issues involved here can only be fully dealt with in a larger perspective, taking volition and other aspects of causality into consideration, as done in Volition and Allied Causal Concepts). Phase I: Macroanalysis. Starting with the paradigm of causation, its most obvious and strongest form, we can by abstraction of its defining components distinguish four genera of causation, or generic determinations, namely: complete, partial, necessary and contingent causation. When these genera and their negations are combined together in every which way, and tested for consistency, it is found that only four species of causation, or specific determinations, remain conceivable. The concept of causation thus gives rise to a number of positive and negative propositional forms, which can be studied in detail with relative ease because they are compounds of conjunctive and conditional propositions whose properties are already well known to logicians. The logical relations (oppositions) between the various determinations (and their negations) are investigated, as well as their respective implications (eductions). Thereafter, their interactions (in syllogistic reasoning) are treated in the most rigorous manner. The main question we try to answer here is: is (or when is) the cause of a cause of something itself a cause of that thing, and if so to what degree? The figures and moods of positive causative syllogism are listed exhaustively; and the resulting arguments validated or invalidated, as the case may be. In this context, a general and sure method of evaluation called ‘matricial analysis’ (macroanalysis) is introduced. Because this (initial) method is cumbersome, it is used as little as possible – the remaining cases being evaluated by means of reduction. Phase II: Microanalysis. Seeing various difficulties encountered in the first phase, and the fact that some issues were left unresolved in it, a more precise method is developed in the second phase, capable of systematically answering most outstanding questions. This improved matricial analysis (microanalysis) is based on tabular prediction of all logically conceivable combinations and permutations of conjunctions between two or more items and their negations (grand matrices). Each such possible combination is called a ‘modus’ and is assigned a permanent number within the framework concerned (for 2, 3, or more items). This allows us to identify each distinct (causative or other, positive or negative) propositional form with a number of alternative moduses. This technique greatly facilitates all work with causative and related forms, allowing us to systematically consider their eductions, oppositions, and syllogistic combinations. In fact, it constitutes a most radical approach not only to causative propositions and their derivatives, but perhaps more importantly to their constituent conditional propositions. Moreover, it is not limited to logical conditioning and causation, but is equally applicable to other modes of modality, including extensional, natural, temporal and spatial conditioning and causation. From the results obtained, we are able to settle with formal certainty most of the historically controversial issues relating to causation. Phase III: Software Assisted Analysis. The approach in the second phase was very ‘manual’ and time consuming; the third phase is intended to ‘mechanize’ much of the work involved by means of spreadsheets (to begin with). This increases reliability of calculations (though no errors were found, in fact) – but also allows for a wider scope. Indeed, we are now able to produce a larger, 4-item grand matrix, and on its basis find the moduses of causative and other forms needed to investigate 4-item syllogism. As well, now each modus can be interpreted with greater precision and causation can be more precisely defined and treated. In this latest phase, the research is brought to a successful finish! Its main ambition, to obtain a complete and reliable listing of all 3-item and 4-item causative syllogisms, being truly fulfilled. This was made technically feasible, in spite of limitations in computer software and hardware, by cutting up problems into smaller pieces. For every mood of the syllogism, it was thus possible to scan for conclusions ‘mechanically’ (using spreadsheets), testing all forms of causative and preventive conclusions. Until now, this job could only be done ‘manually’, and therefore not exhaustively and with certainty. It took over 72’000 pages of spreadsheets to generate the sought for conclusions. This is a historic breakthrough for causal logic and logic in general. Of course, not all conceivable issues are resolved. There is still some work that needs doing, notably with regard to 5-item causative syllogism. But what has been achieved solves the core problem. The method for the resolution of all outstanding issues has definitely now been found and proven. The only obstacle to solving most of them is the amount of labor needed to produce the remaining (less important) tables. As for 5-item syllogism, bigger computer resources are also needed. (shrink)

This short paper is a "quick and dirty" introduction for non-philosophers (with some background in propositional logic) to Jaegwon Kim's famous supervenience argument against non-reductive physicalism (also known as the exclusion problem). It motivates the problem of mental causation, introduces Kim's formulation of the issue centered around mind-body supervenience, presents the argument in deductive form, and makes explicit why Kim concludes that vindicating mental causation demands a reduction of mind.

As soon as you believe an imagination to be nonfictional, this imagination becomes your ontological theory of the reality. Your ontological theory (of the reality) can describe a system as the reality. However, actually this system is only a theory/conceptual-space/imagination/visual-imagery of yours, not the actual reality (i.e., the thing-in-itself). An ontological theory (of the reality) actually only describes your (subjective/mental) imagination/visual-imagery/conceptual-space. An ontological theory of the reality, is being described as a situation model (SM). There is no way to prove/disprove (...) that there is only one reality, or there are two realities (i.e., “subjective reality” and “objective reality”). So, every ontology talk/theory/imagination about the two realities is only a talk/theory/imagination – we will never know whether it is true or not. The conventionally-called “physical/objective reality/world” around my conventionally-called “physical/objective body” is actually a geometric mathematical model (being generated/mathematically-modeled by my brain) – it's actually a subset/component/part/element of my brain’s mind/consciousness/manifest-image. Our cosmos is an autonomous objective parallel computing automaton (aka state machine) which evolves by itself automatically/unintentionally – wave-particle duality and Heisenberg’s uncertainty principle can be explained under this SM of my brain. Each elementary particle (as a building block of our cosmos) is an autonomous mathematical entity itself (i.e., a thing in itself). Our cosmos has the same nature as a Game of Life system – both are autonomous objective parallel-computing automata. Cosmos (as a state machine) is indistinguishable from a digital simulation – my consciousness (as something nonphysical) is not cosmos (as a state machine). If we are happy to accept randomness/stochasticity, then it is obviously possible that all other worlds in the many-worlds interpretation (MWI) actually do not exist (objectively). As one metaphysical option, we can treat all other worlds as subjective only (even if they are actually objective). Under the context of this metaphysical option, we are only living in one world (i.e., the world we are currently living in; this world) – we are not living in many worlds at the same time parallelly. Under the context of this metaphysical option, there is only one possible future. The relationship among any number of elementary particles, is governed/described by Schrodinger equation. If (in theory) Schrodinger equation can’t be used to reliably forecast whether I will go to McDonald for dinner in this world (based on the current state of all elementary particles of the cosmos), then what can Schrodinger equation do? The conventionally-called “space” does not exist objectively. “Time” and “matter” are not physical. Consciousness is the subjective-form (aka quale) of the mathematical models (of the objective cosmos) which are intracorporeally/subjectively used by the control logic of a Turing machine’s program fatedly. A Turing machine’s mind/consciousness/manifest-image or deliberate decisions/choices should not be able to actually/objectively change/control/drive the (autonomous or fated) worldline of any elementary particle within this world (i.e., the world we are currently living in, under the context of MWI). Besides the Schrodinger equation (or another mathematical equation/function which is yet to be discovered) which is a valid/correct/factual causality of our cosmos/state-machine, every other causality (of our cosmos/state-machine) is either invalid/incorrect/counterfactual or can be proved by deductive inference based on the Schrodinger equation (or the aforementioned yet-to-be-discovered mathematical equation/function) only. Closed causality entails no causality. Consciousness plays no causal role (“epiphenomenalism”), or in other words, any cognitive/behavioural activity can in principle be carried out without consciousness (“conscious inessentialism”). If the “loop quantum gravity” theory is correct, then time/space does not actually/objectively exist in the objective-evolution of the objective cosmos, or in other words, we should not use the subjective/mental concept of “time”, “state” or “space” to describe/imagine the objective-evolution of our cosmos. (shrink)

This presentation includes a complete bibliography of John Corcoran’s publications relevant on Aristotle’s logic. The Sections I, II, III, and IV list respectively 23 articles, 44 abstracts, 3 books, and 11 reviews. Section I starts with two watershed articles published in 1972: the Philosophy & Phenomenological Research article—from Corcoran’s Philadelphia period that antedates his discovery of Aristotle’s natural deduction system—and the Journal of Symbolic Logic article—from his Buffalo period first reporting his original results. It ends with works published in (...) 2015. Some items are annotated as listed or with endnotes connecting them with other work and pointing out passages that, in retrospect, are seen to be misleading and in a few places erroneous. In addition, Section V, “Discussions”, is a nearly complete secondary bibliography of works describing, interpreting, extending, improving, supporting, and criticizing Corcoran’s work: 10 items published in the 1970s, 24 in the 1980s, 42 in the 1990s, 60 in the 2000s, and 70 in the current decade. The secondary bibliography is also annotated as listed or with endnotes: some simply quoting from the cited item, but several answering criticisms and identifying errors. Section VI, “Alternatives”, lists recent works on Aristotle’s logic oblivious of Corcoran’s research and, more generally in some cases, even of the Łukasiewicz-initiated tradition. As is evident from Section VII, “Acknowledgements”, Corcoran’s publications benefited from consultation with other scholars, most notably George Boger, Charles Kahn, John Mulhern, Mary Mulhern, Anthony Preus, Timothy Smiley, Michael Scanlan, Roberto Torretti, and Kevin Tracy. All of Corcoran’s Greek translations were done in collaboration with two or more classicists. Corcoran never published a sentence without discussing it with his colleagues and students. (shrink)

In the proof-theoretic semantics approach to meaning, harmony , requiring a balance between introduction-rules (I-rules) and elimination rules (E-rules) within a meaning conferring natural-deduction proof-system, is a central notion. In this paper, we consider two notions of harmony that were proposed in the literature: 1. GE-harmony , requiring a certain form of the E-rules, given the form of the I-rules. 2. Local intrinsic harmony : imposes the existence of certain transformations of derivations, known as reduction and expansion . (...) We propose a construction of the E-rules (in GE-form) from given I-rules, and prove that the constructed rules satisfy also local intrinsic harmony. The construction is based on a classification of I-rules, and constitute an implementation to Gentzen’s (and Pawitz’) remark, that E-rules can be “read off” I-rules. (shrink)

ABSTRACT: For the Stoics, a syllogism is a formally valid argument; the primary function of their syllogistic is to establish such formal validity. Stoic syllogistic is a system of formal logic that relies on two types of argumental rules: (i) 5 rules (the accounts of the indemonstrables) which determine whether any given argument is an indemonstrable argument, i.e. an elementary syllogism the validity of which is not in need of further demonstration; (ii) one unary and three binary argumental rules which (...) establish the formal validity of non-indemonstrable arguments by analysing them in one or more steps into one or more indemonstrable arguments (cut type rules and antilogism). The function of these rules is to reduce given non-indemonstrable arguments to indemonstrable syllogisms. Moreover, the Stoic method of deduction differs from standard modern ones in that the direction is reversed (similar to tableau methods). The Stoic system may hence be called an argumental reductive system of deduction. In this paper, a reconstruction of this system of logic is presented, and similarities to relevance logic are pointed out. (shrink)

In the article I deal with some paradoxes and errors caused by improper usage of logical and philosophical terms appearing in the arguments for existence of god and other philosophical issues. I point at rst some paradoxes coming om improper usage of propositional calculus as an instrument for analysis of a natural language. this language is actually not using simple sentences but rather propositional functions, their logical connections, and some replacements for variables in them. We still have to deal with (...) so called paradox of material implication. the second paragraph provides formal and metatheoretical critics of Charles Sanders Peirce’s theory of deduction, induction and abduction. I argue that what Peirce and his followers call abduction is actually deduction or some reasoning unable to describe in terms of the logic used by them. Both syllogistic and inferential theory of abduction generate some paradoxes and contradictions. In the last paragraph also some paradoxes and contradictions resulting om the theory of causation by Jan Łukasiewicz are presented. the central issue of the article is erroneous usage of the implication: in logical paraphrases of a natural language, in description of the scienti c reasoning, and in description of causality. However, my objective is not to solve all problems mentioned above but rather to open a discussion over them. (shrink)

Dretske makes arguments in which he suggests three levels of the intentionality of knowledge: (1) a low level belonging to law-like causal relationships between physical properties, (2) a middle level defined in terms of the intensionality of sentences describing knowledge of these properties, and (3) a highest level of human cognition. Acknowledging the need to explain humans’ analytic knowledge, however, he proposes that we know a proposition P analytically when we know that P entails Q, even though P and Q (...) are not identical. -/- I explore examples of deduction involving properties of every-day life, such as being a bachelor, being a stay-at-home mom, and being a consultant. I argue that to make these common sense inferences, the average person has to be aware of both analytical entailments and propositional entailments. While the former simply is knowing that if Emily is a stay-at-home mom, then Emily is female, for example, the latter requires us to be conscious of the (often complex) logical structure given to our beliefs by the deductive connectives AND, NOT, and OR. From an empirical standpoint, there are two general possibilities for reductive accounts of these kinds of awareness. One would be a counterfactually defined set of causal criteria, such as Dretske’s. The other would involve statistical patterns of synaptic connections between neural phenomena, whose firings represent our concepts for AND, NOT, and OR. I argue that neither of these reductive explanations is viable; and that in order to explain the success of our inferences, we must appeal to two kinds of higher cognitive intentionality. First, we usually have some conscious awareness of analytical and propositional entailments when we engage in common sense-based deduction. Second, we often have a conscious intention to think deductively during these inferences, which drives our success. (shrink)

In response to the claim that certain epistemically defective inferences such as Moore’s argument lead us to the conclusion that we ought to abandon closure, Crispin Wright suggests that we can avoid doing so by distinguishing it from a stronger principle, namely transmission. Where closure says that knowledge of a proposition is a necessary condition on knowledge of anything one knows to entail it, transmission makes a stronger claim, saying that by reasoning deductively from known premises one can thereby acquire (...) knowledge of or justification for the conclusion. Wright’s thought is that in cases such as Moore what is really going on is a failure of transmission, not a failure of closure. The problem with this claim is that it relies on an outdated formulation of closure which few nowadays would find plausible. Once we stipulate that it is the intuitive closure principle that deserves our attention, it becomes far less obvious that the project of diagnosing what is wrong with arguments such as Moore in terms of transmission failure but not closure failure can be vindicated. In order to demonstrate this claim, I consider intuitive closure of propositional justification vs. transmission of propositional justification and concede that perhaps these can come apart in the way that Wright suggests. I then argue that despite this concession, we also need an answer to the question of whether intuitive closure for doxastic justification and transmission for doxastic justification can come apart. We need an answer to this question because our ultimate interest in these issues stems from our interest in whether knowledge obeys closure, not merely whether propositional justification does. I argue that, even on the assumption that there is transmission failure of propositional justification, there is no transmission failure of doxastic justification. And if this is true, then there is no transmission failure of knowledge either. The transmission failure diagnosis of Moore’s argument and its ilk is thus in trouble. (shrink)

Neural activity varies continually from moment to moment. Such temporal variability (TV) has been highlighted as a functionally specific brain property playing a fundamental role in cognition. We sought to investigate the mechanisms involved in TV changes between two basic behavioral states, namely having the eyes open (EO) or eyes closed (EC) in vivo in humans. To these ends we acquired BOLD fMRI, ASL, and [18F]-fluoro-deoxyglucose PET in a group of healthy participants (n = 15), along with BOLD fMRI and (...) [18F]-flumazenil PET in a separate group (n = 19). Focusing on an EO- vs EC-sensitive region in the occipital cortex (identified in an independent sample), we show that TV is constrained in the EO condition compared to EC. This reduction is correlated with an increase in energy consumption and with regional GABAA receptor density. This suggests that the modulation of TV by behavioral state involves an increase in overall neural activity that is related to an increased effect from GABAergic inhibition in addition to any excitatory changes. These findings contribute to our understanding of the mechanisms underlying activity variability in the human brain and its control. (shrink)

Although the theory of the assertoric syllogism was Aristotle's great invention, one which dominated logical theory for the succeeding two millenia, accounts of the syllogism evolved and changed over that time. Indeed, in the twentieth century, doctrines were attributed to Aristotle which lost sight of what Aristotle intended. One of these mistaken doctrines was the very form of the syllogism: that a syllogism consists of three propositions containing three terms arranged in four figures. Yet another was that a syllogism is (...) a conditional proposition deduced from a set of axioms. There is even unclarity about what the basis of syllogistic validity consists in. Returning to Aristotle's text, and reading it in the light of commentary from late antiquity and the middle ages, we find a coherent and precise theory which shows all these claims to be based on a misunderstanding and misreading. (shrink)

There are three theories in the epistemology of modality that have received sustained attention over the past 20 years: conceivability-theory, counterfactual-theory, and deduction-theory. In this paper we argue that all three face what we call the problem of modal epistemic friction. One consequence of the problem is that for any of the three accounts to yield modal knowledge, the account must provide an epistemology of essence. We discuss an attempt to fend off the problem within the context of the (...) internalism versus externalism debate about epistemic justification. We then investigate the effects that the PMEF has on reductive and non-reductive theories of the relation between essence and modality. (shrink)

The intuitive distinction between natural and unnatural properties (e.g., green vs. grue) informs our theorizing not only in fundamental physics, but also in non-fundamental domains. This paper develops a reductive account of this broad notion of naturalness that covers non-fundamental properties: for a property to be natural, I propose, is for it to figure in a law of nature. After motivating the account, I defend it from a potential circularity charge. I argue that a suitably broad notion of lawhood can (...) be defined independently of naturalness, if we help ourselves to the notion of a fundamental physical property. I end by showing how the notions of naturalness and lawhood that my account delivers help illuminate a number of other important philosophical notions, like causation, reference/meaning, and rational induction. (shrink)

(...) However, whether we chose a weak or strong approximation, the set would not make any sense at all, if (once more) this choice would not be justified in either temporal or spatial sense or given the context of possible applicability of the set in different circumstances. This would obviously represent a dualism in itself as we would (for instance) posit and apply a full identity-equality-equivalence of x and y when applying Newtonian physics to certain observations we make (it would (...) be the case of neural correlates), and we would posit and apply a non - identity-equality-equivalence of x and y when applying Quantum mechanics to other observations. Following this dualism in and of theories, the same sate would need to be slightly modified: U2:(x~y)∪(x≈y); U3:(x~y)∩(x≈y); U4a:(x~y)⊆(x≈y) vs. U4b:(x~y)⊇(x≈y). (shrink)

Bilateralists hold that the meanings of the connectives are determined by rules of inference for their use in deductive reasoning with asserted and denied formulas. This paper presents two bilateral connectives comparable to Prior's tonk, for which, unlike for tonk, there are reduction steps for the removal of maximal formulas arising from introducing and eliminating formulas with those connectives as main operators. Adding either of them to bilateral classical logic results in an incoherent system. One way around this problem (...) is to count formulas as maximal that are the conclusion of reductio and major premise of an elimination rule and to require their removability from deductions. The main part of the paper consists in a proof of a normalisation theorem for bilateral logic. The closing sections address philosophical concerns whether the proof provides a satisfactory solution to the problem at hand and confronts bilateralists with the dilemma that a bilateral notion of stability sits uneasily with the core bilateral thesis. (shrink)

This paper studies a formalisation of intuitionistic logic by Negri and von Plato which has general introduction and elimination rules. The philosophical importance of the system is expounded. Definitions of ‘maximal formula’, ‘segment’ and ‘maximal segment’ suitable to the system are formulated and corresponding reduction procedures for maximal formulas and permutative reduction procedures for maximal segments given. Alternatives to the main method used are also considered. It is shown that deductions in the system convert into normal form and (...) that deductions in normal form have the subformula property. (shrink)

This paper considers a formalisation of classical logic using general introduction rules and general elimination rules. It proposes a definition of ‘maximal formula’, ‘segment’ and ‘maximal segment’ suitable to the system, and gives reduction procedures for them. It is then shown that deductions in the system convert into normal form, i.e. deductions that contain neither maximal formulas nor maximal segments, and that deductions in normal form satisfy the subformula property. Tarski’s Rule is treated as a general introduction rule for (...) implication. The general introduction rule for negation has a similar form. Maximal formulas with implication or negation as main operator require reduction procedures of a more intricate kind not present in normalisation for intuitionist logic. (shrink)

David Lewis (1974, 1994/1999) proposed to reduce the facts about mental representation to facts about sensory evidence, dispositions to act, and rationality. Recently, Robert Williams (2020) and Adam Pautz (2021) have taken up and developed Lewis’s project in sophisticated and novel ways. In this paper, we aim to present, clarify, and ultimately object to the core thesis that they all build their own views around. The different sophisticated developments and defenses notwithstanding, we think the core thesis is vulnerable. We pose (...) a dilemma by considering the two sides of a current epistemological controversy over the relation between evidence and rational belief: permissivism vs. uniqueness. As we argue, the prospects for the Lewisian project look dim when either supposition is clearly made. (shrink)

La position résolument extensionaliste de Quine a été appuyée par des arguments de nature différente, dans ses multiples articles destinés à rejeter le projet de logique modale. On peut classer ces arguments en trois catégories : un argument naturaliste, où l’auteur tente de baser le langage scientifique sur une notation tâchée de décrire la “structure ultime de la réalité” ; un argument esthétique, où Quine fait allusion à des raisons de clarté et d’efficacité démonstrative pour privilégier la théorie des fonctions (...) de vérité ; un argument pratique, dans la mesure où Quine défend la logique classique sur la base du “principe de mutilation minimum”. A travers une étude de ses écrits relatifs aux attitudes propositionnelles, nous montrerons que la philosophie de la logique de Quine a prolongé la partie épistémologique de son oeuvre, optant finalement pour une stratégie de réduction naturaliste des intensions, à l’image du mouvement engagé par Word and Object et prolongé par From Stimulus to Science. Ce projet se soldera par un échec relatif, et Quine résumera cette désillusion par un fossé entre les structures du langage et du monde : la thèse du “monisme anomal” de Davidson sera le dernier mot, amer, du défenseur acharné de la logique classique. (shrink)

The critique of philosophical foundations of neoclassical economics is significant, because of its hegemony on economic education and research programs in Iran and worldwide academies. Due to an epistemological fallacy, methodological individualism plays a prominent role in the philosophy of economic; since the ontological aspects of economy are reduced to methodological considerations. Accordingly, critique of methodological individualism is regarded as the main entry for philosophical analysis of neoclassical economics. This article aims to analyze and appraise the methodological individualism from critical (...) realism’s point of view. Critical realism is taken as a stand for criticizing methodological individualism, because critical realism and neoclassical economics as a positive approach to economics, both share a realistic worldview. The critical realism’ critique of methodological individualism is bases on analyzing the concepts of formalism, syllogism, social atomism, isolation and reduction. From critical realism’ point of view because of unrealistic postulations of methodological individualism, neoclassical economics is turned to an abstract and deductive science such as mathematics with a low potentiality of explanation. (shrink)

Notes mainly on model-oriented vs. deduction-oriented conceptions of axiomatic reasoning.

Logical and philosophical literature provides different classifications of reasoning. In the Polish literature on the subject, for instance, there are three popular ones accepted by representatives of the Lvov-Warsaw School: Jan Łukasiewicz, Tadeusz Czeżowski and Kazimierz Ajdukiewicz (Ajdukiewicz in Logika pragmatyczna [Pragmatic Logic]. PWN, Warsaw (1965, 2nd ed. 1974). Translated as: Pragmatic Logic. Reidel & PWN, Dordrecht, 1975). The author of this paper, having modified those classifications, distinguished the following types of reasoning: (1) deductive and (2) non-deductive, and additionally two (...) types of them in each of the two, depending on the manner of combining their premises with the conclusion through the relation of classical logical entailment. Consequently, the four types of reasoning: unilateral deductive (incl. its sub-types: deductive inference and proof), bilateral deductive (incl. complete induction), and reductive (incl. the sub-types: explanation and verification), logically nonvaluable (incl. inference by analogy, statistic inference), correspond to four operators of derivability. They are defined formally on the ground of Tarski’s axiomatic theory of deductive systems, by means of the consequence operation _Cn_ (Tarski in Monatshefte Math Phys 37:361–404, 1930a, C R Soc Sci Lett Vars 23:22–29, 1930b). Also, certain metalogical properties of these operators are given, as well as their relations with Tarski’s consequence operations \(Cn^+\) ( \(Cn^+ = Cn\) ) and dual consequences \(Cn^{-1}\) (Słupecki in Zeszyty Naukowe Uniwersytetu Wrocławskiego Seria B Nr 3:33–40, 1959, Słupecki et al. in Stud Log 29:76–123, 1971, Wybraniec-Skardowska, in: Wybraniec-Skardowska, Bryll (eds) Z badań nad teorią zdań odrzuconych [Studies in the Theory of Rejected Propositions], Series B, Studia i Monografie, Zeszyty Naukowe Wyższej Szkoły Pedagogicznej w Opolu, Opole, 1969), and \(Cn^-\) (Wójcicki in Bull Sect Log 2(2):54–57, 1973)). (shrink)

1. Introduction: a look back at the reasons vs. causes debate. 2. The interventionist account of causation. 3. Four objections to interventionism. 4. The counterfactual analysis of event causation. 5. The role of free agency. 6. Causality in the human sciences. -- The reasons vs. causes debate reached its peak about 40 years ago. Hempel and Dray had debated the nature of historical explanation and the broader issue of whether explanations that cite an agent’s reasons are causal or not. Melden, (...) Peters, Winch, Kenny and Anscombe had contributed their anticausal conceptions. The neo-Wittgensteinians seemed to be winning the day when in 1963 Donald Davidson published his seminal paper “Actions, Reasons, and Causes”. Davidson’s paper devastated the Wittgensteinian camp. It contained, among other things, a powerful attack on the logical connection argument. Davidson argued that the existence of a logical or conceptual connection between descriptions can never eliminate a causal relation, which holds between events simpliciter, not between events under certain descriptions. Davidson maintained that in a way, reasons can be causes. When somebody acts for a certain reason, his intentional attitudes, or rather changes in his attitudes, cause his bodily movements. Davidson also argued that rationalization is a species of causal explanation. For the definition of action, he argued that intentional actions are bodily movements caused in the right way by beliefs and desires that rationalize them. Davidson’s paper paved the way for causal theories of action, which superseded neo-Wittgensteinian analyses in the following decades. The causal theory was rapidly adopted by Alvin Goldman, David Armstrong, Paul Churchland, Myles Brand and many others, entering the mainstream and dominating the philosophy of action to this very day. In 1971 Georg Henrik von Wright published his book "Explanation and Understanding". The second chapter did not deal with agency, but with causation. It developed a new account of causation, the interventionist or experimentalist account. Focusing on causation, von Wright remedied a major shortcoming of the reasons vs. causes debate. The concept of causality, and the nature of the causal relation, received little attention in this debate, a fact that holds true for both camps. Mostly it was simply taken for granted that, as Hempel had declared, “causal explanation is a special type of deductive-nomological explanation”. One camp then aligned intentional explanations with D-N explanations, while the other camp insisted on their disparity. So strictly speaking, the label “reasons/causes debate” was a misnomer. The controversy dealt primarily with the question as to whether intentional explanations can take the form of D-N explanations, while the notion of causation, and the metaphysics of the causal relation, were left obscured. With von Wright’s new approach, the situation changed. Von Wright was primarily concerned with causation, but his approach contained an implicit attack on the causal theory of action as well. His core idea was that the notion of causality is intimately linked with, or even derived from, the notion of intentionally making something happen. Other philosophers, even Hume, had considered such a connection before, but often just to reject this view, regarding it as a kind of myth belonging to the infancy of the human mind. Von Wright took the idea seriously. He submitted the analysis that p is the cause of q if and only if by doing p we could bring about q. The causal theory of action was also concerned with the relation between causation and agency, to which its name bears witness. The causal theory of action holds that actions are bodily movements with a certain causal history. This is why von Wright’s account constituted a momentous challenge to the causal theory: it reversed the direction of conceptual dependency between both notions. Davidson and his followers tried to define what an intentional action is by using the notion of causation. The causal condition which the causal theory sets is part of the definition of “doing something intentionally”. Von Wright claimed that the conceptual dependency is the other way round. He used the notions of doing, and bringing about, to explain what causal relations are. So, instead of a causal theory of action, he advocated an agency theory of causation, as it may be dubbed. It is remarkable how seldom this clash of opinions about conceptual primacy is reflected in the literature. There are few exceptions: Fred Stoutland noticed the conflict, and he published a number of papers in which he compared Davidson’s and von Wright’s views. Von Wright’s book "Explanation and Understanding" was widely read and discussed in the seventies, especially in Europe. But it strikes me that especially in North America, where the causal theory of action became the orthodoxy of the day, von Wright’s challenge went largely unnoticed. Even Davidson did not seem to take it seriously. He nowhere takes notice of the interventionist theory of causation, while he does discuss von Wright’s earlier book "Norm and Action". As is well-known, Davidson favoured an alternative account of causation, based on “the principle of the nomological character of causality”, as he somewhat clumsily called it, or, later and less clumsily, “the cause-law thesis”. Davidson’s firm adherence to a nomological theory of causality may explain why he did not take much interest in alternative accounts. [...] -/- . 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Husserl’s phenomenology opens itself with a critique of positive sciences. Husserl problematizes the hardcore presupposition of positivism that the world is a definite sort of an existential totality of objects and thus it is exhaustible with empirical data and deductive-conceptual abstraction on the basis of causalspatio-temoprality. Criticizing the wholesome reduction of nature into a physical reality and the instrumentalizing of theoretical reason, he proposes transcendental phenomenology, as an ideal form of science. Self-entitled as the genuine science, the science of (...) origin, the science of all sciences, etc., it concerns itself with the matter of validity. Claiming that validating objectivity as such and the meaning of scientific objectification is something of which onlyphenomenological reflection on pure consciousness is capable and that the positivistic objectivity is and must be founded on transcendental subjectivity, Husserl radically idealistically revised the whole positivistic concept of evidence and givenness of a fact and substituted it with the phenomenological notion of apriori self-evidence and originary givenness of primordial intentional consciousness. Nevertheless, it is noticed that the absolute universal validity of positivistic objectivity was never rejected or questioned; objectivity is still in and of itself an absolute criterion of scientificity in Husserl. This paper will argue that the idealistic turn toward subjectivity takes place through factualization of transcendentality and this, by bestowing apriori apodicticity with facticity, even enhances more the supreme epistemological function of positivity. It will discuss such positivistic drive, directly bequeathed from the very cultural ethos at which phenomenological criticism targeted, as an important locomotive for Husserl’s program and point out an antinomical consequence with which it is to be faced as a consequence. (shrink)

The fundamental assumption of Dummett’s and Prawitz’ proof-theoretic justification of deduction is that ‘if we have a valid argument for a complex statement, we can construct a valid argument for it which finishes with an application of one of the introduction rules governing its principal operator’. I argue that the assumption is flawed in this general version, but should be restricted, not to apply to arguments in general, but only to proofs. I also argue that Dummett’s and Prawitz’ project (...) of providing a logical basis for metaphysics only relies on the restricted assumption. (shrink)

This article describes a case of a teenager with early complex trauma due to chronic domestic violence. Cannabis use triggered auditory hallucinations, after which the teenager was diagnosed with an acute schizophrenia-like psychotic disorder. Antipsychotic medication did not fully resolve symptoms. Eventually the teenager chose to self-medicate with LSD in order to resolve a suicidal condition. The teenager carried out six unsupervised LSD sessions, followed by an extended period of almost daily use of inhaled low-dose DMT. Psychotic symptoms were mostly (...) resolved after approximately one year. Subsequent cannabis use caused a transient relapse. -/- While his psychosis may have been due to cannabis use in the presence of a genetic predisposition, LSD and DMT did not promote psychotic symptoms in this case, and resolved the suicidal condition in one session. Additional high-dose LSD sessions and low-dose DMT sessions appeared to resolve the symptoms related to the early complex trauma. Alternatively, if psychosis is understood as a massive defense system resulting from early complex trauma, and if his psychotic symptoms were partially due to such trauma, psychedelics appeared to transcend this defense system, providing access to traumatic memories in order to allow for an integrative treatment effect. -/- Information was acquired from medical record excerpts provided by the patient, a semi-structured retrospective video interview, and follow-up interviews a year later. The present case suggests a need for further studies on the relationship between psychedelics and psychotic disorders, the feasibility of supervised vs unsupervised settings for various situations, and alternative therapeutic models for utilizing the hyperaware-hypersensitive state induced by psychedelics. With regard to self-treatment, a harm reduction approach should be adopted. Low-risk psycholytic self-treatment protocols could be developed for future use in public health care systems. (shrink)

This interesting and imaginative monograph is based on the author’s PhD dissertation supervised by Saul Kripke. It is dedicated to Timothy Smiley, whose interpretation of PRIOR ANALYTICS informs its approach. As suggested by its title, this short work demonstrates conclusively that Aristotle’s syllogistic is a suitable vehicle for fruitful discussion of contemporary issues in logical theory. Aristotle’s syllogistic is represented by Corcoran’s 1972 reconstruction. The review studies Lear’s treatment of Aristotle’s logic, his appreciation of the Corcoran-Smiley paradigm, and his understanding (...) of modern logical theory. In the process Corcoran and Scanlan present new, previously unpublished results. Corcoran regards this review as an important contribution to contemporary study of PRIOR ANALYTICS: both the book and the review deserve to be better known. (shrink)

The premise-fact confusion in Aristotle’s PRIOR ANALYTICS. -/- The premise-fact fallacy is talking about premises when the facts are what matters or talking about facts when the premises are what matters. It is not useful to put too fine a point on this pencil. -/- In one form it is thinking that the truth-values of premises are relevant to what their consequences in fact are, or relevant to determining what their consequences are. Thus, e.g., someone commits the premise-fact fallacy if (...) they think that a proposition has different consequences were it true than it would have if false. C. I. Lewis said that confusing logical consequence with material consequence leads to this fallacy. See Corcoran’s 1973 “Meanings of implication” [available on Academia. edu]. -/- The premise-fact confusion occurs in a written passage that implies the premise-fact fallacy or that suggests that the writer isn’t clear about the issues involved in the premise-fact fallacy. Here are some examples. -/- E1: If Abe is Ben and Ben swims, then it would follow that Abe swims. -/- Comment: The truth is that from “Abe is Ben and Ben swims”, the proposition “Abe swims” follows. Whether in fact Abe is Ben and Ben swims is irrelevant to whether “Abe swims” follows from “Abe is Ben and Ben swims”. -/- E1 suggests that maybe “Abe swims” wouldn’t follow from “Abe is Ben and Ben swims” if the latter were false. -/- E2: The truth of “Abe is Ben and Ben swims” implies that Abe swims. -/- E3: Indirect deduction requires assuming something false. -/- Comment: If the premises of an indirect deduction are true the conclusion is true and thus the “reductio” assumption is false. But deduction, whether direct or indirect, does not require true premises. In fact, indirect deduction is often used to determine that the premises are not all true. -/- Anyway, the one-page paper accompanying this abstract reports one of dozens of premise-fact errors in PRIOR ANALYTICS. In the session, people can add their own examples and comment on them. For example, is the one at 25b32 the first? What is the next premise-fact error after 25b32? Which translators or commentators discuss this? -/- . (shrink)

When approaching the nature and etiology of psychophysical problems in a given population, it is important to understand the causal relations, the mechanisms, and the processes which underlie given problems, issues, and disorders. This examination attempts to investigate the connection between neural pathophysiology and proprioceptive ontology of olfactory and visual cortical circuitry on the basis of the current scientific evidence indicated by the results of studies in which subjects underwent a series of therapeutic modalities focused on the improvement of overall (...) wellbeing with the utilization of devices and technologies to stimulate multiple motor vs. somatosensory processes. More specifically, the studies at the centers of this analysis incorporated physical movement and virtual reality interactions, with the supplement of olfactory stimulation. In this examination, such research is also investigated from a theoretical standpoint, with the ultimate goal to better determine which interventions are justified under the premise of a mutual support between empirical values (through laboratory examination) and logical deduction (via philosophical investigation). (shrink)

In the mid-1960s, Soviet computer scientist Mikhail Moiseevich Bongard created sets of visual puzzles where the objective was to spot an easily justifiable difference between two sides of a single image (for instance, white shapes vs black shapes, etc...). The idea was that these puzzles could be used to teach computers the general faculty of abstraction: perhaps by learning to spot the differences between these sorts of images, a computational agent could learn about inference in general. Considered a global expert (...) on Bongard problems, cognitive scientist Harry Foundalis developed the Phaeaco cognitive architecture for his PhD thesis - based on emulating cognition by solving the problems, creating a kind of artificial intelligence. In this paper, the extent to which Foundalis' approach allows for artificial general intelligence (the ability to reproduce a wide range of human abilities, or the goal of cognitive models) will be evaluated - with reference to Daniel Dennett’s reductive theory of mind and Immanuel Kant’s concept of the phenomenon and the noumenon. The point of view presented is that Phaeaco is missing several characteristics of general artificial intelligence. (shrink)

As noted in 1962 by Timothy Smiley, if Aristotle’s logic is faithfully translated into modern symbolic logic, the fit is exact. If categorical sentences are translated into many-sorted logic MSL according to Smiley’s method or the two other methods presented here, an argument with arbitrarily many premises is valid according to Aristotle’s system if and only if its translation is valid according to modern standard many-sorted logic. As William Parry observed in 1973, this result can be proved using my 1972 (...) proof of the completeness of Aristotle’s syllogistic. (shrink)

Objective: Atlas is located at a critical point close to the vital centers of the medulla oblongata, which can be compressed by the dislocation of the atlantoaxial complex or instability of the atlantooccipital joint. This study aimed to determine in detail the morphometric and morphological characteristics of the atlas to guide the reduction of the risk of complications and increase the success rate in various surgical approaches for the craniovertebral junction. -/- Methods: In this study, 17 atlas vertebrae whose (...) measurement parameters were pronounced and unknown gender, age, and ethnic characteristics were examined. -/- Results: Totally 16 parameters, 11 of which were bilateral and 5 were unilateral, were examined on the atlas. Also, no accessory foramen transversarium was found in these atlas vertebrae. Of the 23 foramina transversaria that were prominent and not broken, 7 were found to be round-shaped (30.43%), and 16 were oval-shaped (69.57%). -/- Conclusion: It is deducted that the results obtained in this study will help to have information about the morphometry and morphology of atlas vertebrae. Although information such as age, gender, and ethnic origin is not known about the bones evaluated, it is the advantage of this study that a large number of parameters are evaluated and compared with previous publications. Nevertheless, it seems that there is a need for studies in which much more cases are assessed, and information such as age, gender, and ethnic origin is known. (shrink)

“You have an architect and a ditch-digger working together on a construction project. Who gets paid more, and why?” Does a tendency toward abstraction and quantification, a pretense of objectivity, obscure the character, situation and bias from which all economic and political theorems stem? Following the principle that arguments neither arise nor persist in a vacuum, that they live and die by their context and character, we can describe two sorts of response corresponding to two rather timeless worldviews, along with (...) their accompanying “mind-sets”. The degree to which these views indicate differing “kinds” in human nature, beyond which there can be no further reduction to common ground, whether conversely they simply reflect historical and economic circumstance, or to what extent they are both, will be left to the reader. One might discern in the sensibilities described some alignment along traditional epithets of “bourgeois” vs. “working class”, but this is not necessarily so. I will therefore avoid overwrought labels, but admit that such family resemblances speak to a longer historical view and a persistent problematic. (shrink)

The main objective of this PhD Thesis is to present a method of obtaining strong normalization via natural ordinal, which is applicable to natural deduction systems and typed lambda calculus. The method includes (a) the definition of a numerical assignment that associates each derivation (or lambda term) to a natural number and (b) the proof that this assignment decreases with reductions of maximal formulas (or redex). Besides, because the numerical assignment used coincide with the length of a specific sequence (...) of reduction - the worst reduction sequence - it is the lowest upper bound on the length of reduction sequences. The main commitment of the introduced method is that it is constructive and elementary, produced only through analyzing structural and combinatorial properties of derivations and lambda terms, without appeal to any sophisticated mathematical tool. Together with the exposition of the method, it is presented a comparative study of some articles in the literature that also get strong normalization by means we can identify with the natural ordinal methods. Among them we highlight Howard[1968], which performs an ordinal analysis of Godel’s Dialectica interpretation for intuitionistic first order arithmetic. We reveal a fact about this article not noted by the author himself: a syntactic proof of strong normalization theorem for the system of typified lambda calculus λ⊃ is a consequence of its results. This would be the first strong normalization proof in the literature. (written in Portuguese). (shrink)

Words change meaning, usually in unpredictable ways. But some words’ meanings are revised intentionally. Revisionary projects are normally put forward in the service of some purpose – some serve specific goals of inquiry, and others serve ethical, political or social aims. Revisionist projects can ameliorate meanings, but they can also pervert. In this paper, I want to draw attention to the dangers of meaning perversions, and argue that the self-declared goodness of a revisionist project doesn’t suffice to avoid meaning perversions. (...) The road to Hell, or to horrors on Earth, is paved with good intentions. Finally and more importantly, I want to demarcate what meaning perversions are. This, I hope, can help us assess the moral and political legitimacy of revisionary projects. (shrink)

Localism is the view that the unit of evaluation in the scientific realism debate is a single scientific discipline, sub-discipline, or claim, whereas individualism is the view that the unit of evaluation is a single scientific theory. Localism is compatible, while individualism is not, with a local pessimistic induction and a local selective induction. Asay (2016) presents several arguments to support localism and undercut globalism, according to which the unit of evaluation is the set of all scientific disciplines. I argue (...) that some of his arguments clash with localism as well as with globalism and support individualism, and that individualism goes hand in hand, while localism does not, with the basic rule of how to evaluate an argument. (shrink)

A prominent view of phenomenal consciousness combines two claims: (i) the identity conditions of phenomenally conscious states can be fully accounted for in terms of these states’ representational content; (ii) this representational content can be fully accounted for in non-phenomenal terms. This paper presents an argument against this view. The core idea is that the identity conditions of phenomenally conscious states are not fixed entirely by what these states represent (their representational contents), but depend in part on how they represent (...) (their representational attitudes or modes). The argument highlights the myriad liabilities and difficulties one must accrue when one tries to appeal only to what phenomenally conscious states represent in accounting for their phenomenal individuation. (shrink)

Deductive Cogency holds that the set of propositions towards which one has, or is prepared to have, a given type of propositional attitude should be consistent and closed under logical consequence. While there are many propositional attitudes that are not subject to this requirement, e.g. hoping and imagining, it is at least prima facie plausible that Deductive Cogency applies to the doxastic attitude involved in propositional knowledge, viz. belief. However, this thought is undermined by the well-known preface paradox, leading a (...) number of philosophers to conclude that Deductive Cogency has at best a very limited role to play in our epistemic lives. I argue here that Deductive Cogency is still an important epistemic requirement, albeit not as a requirement on belief. Instead, building on a distinction between belief and acceptance introduced by Jonathan Cohen and recent developments in the epistemology of understanding, I propose that Deductive Cogency applies to the attitude of treating propositions as given in the context of attempting to understand a given phenomenon. I then argue that this simultaneously accounts for the plausibility of the considerations in favor of Deductive Cogency and avoids the problematic consequences of the preface paradox. (shrink)

Dogmatism holds that an experience or seeming that p can provide prima facie immediate justification for believing p in virtue of its phenomenology. Dogmatism about perceptual justification has appealed primarily to proponents of representational theories of perceptual experience. Call dogmatism that takes perceptual experience to be representational "representational phenomenal dogmatism." As we show, phenomenal seemings play a crucial role in dogmatism of this kind. Despite its conventional appeal to representational theorists, dogmatism is not by definition committed to any particular view (...) of perceptual experience. Naive realists and disjunctivists who hold that perceptual experience is a perceptual relation of direct acquaintance can also endorse dogmatism. Indeed, we argue that they ought to do so. Otherwise, they cannot maintain that relationalism about perceptual experience has an epistemic advantage compared to the representational view. We then show that even if we grant that relationalism has this advantage, only dogmatism that takes perceptual experience to be representational can be extended to account for non-deductive inferential justification. As an account of the latter is required to avoid succumbing to skepticism, relationalism, we argue, does not have the epistemic advantage its defenders claim it has. (shrink)

Does the human mind resemble the machines that can behave like it? Biologically inspired machine-learning systems approach “human-level” accuracy in an astounding variety of domains, and even predict human brain activity—raising the exciting possibility that such systems represent the world like we do. However, even seemingly intelligent machines fail in strange and “unhumanlike” ways, threatening their status as models of our minds. How can we know when human–machine behavioral differences reflect deep disparities in their underlying capacities, vs. when such failures (...) are only superficial or peripheral? This article draws on a foundational insight from cognitive science—the distinction between performance and competence—to encourage “species-fair” comparisons between humans and machines. The performance/competence distinction urges us to consider whether the failure of a system to behave as ideally hypothesized, or the failure of one creature to behave like another, arises not because the system lacks the relevant knowledge or internal capacities (“competence”), but instead because of superficial constraints on demonstrating that knowledge (“performance”). I argue that this distinction has been neglected by research comparing human and machine behavior, and that it should be essential to any such comparison. Focusing on the domain of image classification, I identify three factors contributing to the species-fairness of human–machine comparisons, extracted from recent work that equates such constraints. Species-fair comparisons level the playing field between natural and artificial intelligence, so that we can separate more superficial differences from those that may be deep and enduring. (shrink)

In this paper, I consider a family of three-valued regular logics: the well-known strong and weak S.C. Kleene’s logics and two intermedi- ate logics, where one was discovered by M. Fitting and the other one by E. Komendantskaya. All these systems were originally presented in the semantical way and based on the theory of recursion. However, the proof theory of them still is not fully developed. Thus, natural deduction sys- tems are built only for strong Kleene’s logic both with (...) one (A. Urquhart, G. Priest, A. Tamminga) and two designated values (G. Priest, B. Kooi, A. Tamminga). The purpose of this paper is to provide natural deduction systems for weak and intermediate regular logics both with one and two designated values. (shrink)