: The two main psychological theories of the ordinary conditional were designed to account for inferences made from assumptions, but few premises in everyday life can be simply assumed true. Useful premises usually have a probability that is less than certainty. But what is the probability of the ordinary conditional and how is it determined? We argue that people use a two stage Ramsey test that we specify to make probability judgements about indicative conditionals in natural language, and we describe (...) experiments that support this conclusion. Our account can explain why most people give the conditional probability as the probability of the conditional, but also why some give the conjunctive probability. We discuss how our psychological work is related to the analysis of ordinary indicative conditionals in philosophical logic. (shrink)

This Element is on new developments in the psychology of reasoning that raise or address philosophical questions. In traditional studies in the psychology of reasoning, the focus was on inference from arbitrary assumptions and not at all from beliefs, and classical binary logic was presupposed as the only standard for human reasoning. But recently a new Bayesian paradigm has emerged in the discipline. This views ordinary human reasoning as mostly inferring probabilistic conclusions from degrees of beliefs, or from hypothetical premises (...) relevant to a purpose at hand, and as often about revising or updating degrees of belief. This Element also covers new formulations of dual-process theories of the mind, stating that there are two types of mental processing, one rapid and intuitive and shared with other animals, and the other slow and reflective and more characteristic of human beings. The final topic covered is the new developments and rationality. (shrink)

A study is reported testing two hypotheses about a close parallel relation between indicative conditionals, if A then B , and conditional bets, I bet you that if A then B . The first is that both the indicative conditional and the conditional bet are related to the conditional probability, P(B|A). The second is that de Finetti's three-valued truth table has psychological reality for both types of conditional— true , false , or void for indicative conditionals and win , lose (...) , or void for conditional bets. The participants were presented with an array of chips in two different colours and two different shapes, and an indicative conditional or a conditional bet about a random chip. They had to make judgements in two conditions: either about the chances of making the indicative conditional true or false or about the chances of winning or losing the conditional bet. The observed distributions of responses in the two conditions were generally related to the conditional probability, supporting the first hypothesis. In addition, a majority of participants in further conditions chose the third option, “void”, when the antecedent of the conditional was false, supporting the second hypothesis. (shrink)

The new paradigm in the psychology of reasoning adopts a Bayesian, or prob- abilistic, model for studying human reasoning. Contrary to the traditional binary approach based on truth functional logic, with its binary values of truth and falsity, a third value that represents uncertainty can be introduced in the new paradigm. A variety of three-valued truth table systems are available in the formal literature, including one proposed by de Finetti. We examine the descriptive adequacy of these systems for natural language (...) indicative condi- tionals and bets on conditionals. Within our framework the so-called “defective” truth table, in which participants choose a third value when the antecedent of the indicative conditional is false, becomes a coherent response. We show that only de Finetti’s system has a good descriptive fit when uncer- tainty is the third value. (shrink)

The two main psychological theories of the ordinary conditional were designed to account for inferences made from assumptions, but few premises in everyday life can be simply assumed true. Useful premises usually have a probability that is less than certainty. But what is the probability of the ordinary conditional and how is it determined? We argue that people use a two stage Ramsey test that we specify to make probability judgements about indicative conditionals in natural language, and we describe experiments (...) that support this conclusion. Our account can explain why most people give the conditional probability as the probability of the conditional, but also why some give the conjunctive probability. We discuss how our psychological work is related to the analysis of ordinary indicative conditionals in philosophical logic. (shrink)

Oaksford & Chater (O&C) begin in the halfway Bayesian house of assuming that minor premises in conditional inferences are certain. We demonstrate that this assumption is a serious limitation. They additionally suggest that appealing to Jeffrey's rule could make their approach more general. We present evidence that this rule is not limited enough to account for actual probability judgements.

In this collection, leading experts evaluate the status of this controversial field, providing a critical analysis of its main hypotheses These hypotheses have ...

Knauff and Gazzo Castañeda argue as much in support of revised mental model theory (RMMT) as they argue against talk of a new paradigm caused by the probabilistic approach in the psychology of reasoning. They claim that RMMT is not essentially different from classical mental model theory (CMMT) and not essentially different from the probabilistic approach. There are many serious questions to ask about RMMT. But RMMT is a massive modalization of aspects of the extensional CMMT, and it follows the (...) probabilistic approach in having an intensional focus that justifies talk of a new paradigm. (shrink)

Barbey & Sloman (B&S) relegate the logical rule of the excluded middle to a footnote. But this logical rule is necessary for natural sampling. Making the rule explicit in a logical tree can make a problem easier to solve. Examples are given of uses of the rule that are non-constructive and not reducible to a domain-specific module.

We investigate how the perceived uncertainty of a conditional affects a person's choice of conclusion. We use a novel procedure to introduce uncertainty by manipulating the conditional probability of the consequent given the antecedent. In Experiment 1, we show first that subjects reduce their choice of valid conclusions when a conditional is followed by an additional premise that makes the major premise uncertain. In this we replicate Byrne. These subjects choose, instead, a qualified conclusion expressing uncertainty. If subjects are given (...) a third statement that qualifies the likelihood of the additional premise, then the uncertainty of the conclusions they choose is systematically related to the suggested uncertainty. Experiment 2 confirms these observations in problems that omit the additional premise and qualify the first premise directly. Experiment 3 shows that the qualifying statement also affects the perceived probability of the consequent given the antecedent of the conditional. Experiment 4 investigates the effect of suggested uncertainty on the fallacies and shows that increases in uncertainty reduce the number of certain conclusions that are chosen while affirming the consequent but have no effect on denying the antecedent. We discuss our results in terms of rule theories and mental models and conclude that the latter give the most natural account of our results. (shrink)

Four experiments investigated uncertainty about a premise in a deductive argument as a function of the expertise of the speaker and of the conversational context. The procedure mimicked everyday reasoning in that participants were not told that the premises were to be treated as certain. The results showed that the perceived likelihood of a conclusion was greater when the major or the minor premise was uttered by an expert rather than a novice (Experiment 1). The results also showed that uncertainty (...) about the conclusion was higher when the major premise was uttered by a novice and an alternative premise by an expert, compared to when the major premise was uttered by an expert and the alternative by a novice (Experiment 2). Similarly, the believability of a conclusion was considerably lower when the minor premise was uttered by a novice and denied by an expert, as opposed to when an expert uttered the minor premise and a novice denied it (Experiment 3). Experiment 4 showed that the nature of the uncertainty induced by a denial of the minor premise depended on whether or not the context was a conversation. These results pose difficult problems for current theories of reasoning, as current theories are based on the results of experiments in which the premises are treated as certain. Our discussion of the results emphasises the importance of pragmatics in reasoning, namely, the role of general knowledge about the world in assessing the probability of a premise uttered by an expert or a novice and the role of interpretations of the premise based on pragmatic inferences in revising these initial probabilities. (shrink)

The following values have no corresponding Zotero field: PB - Lawrence Erlbaum Associates Ltd Hove,, UK.

Two experiments using a realistic version of the selection task examined the relationship between participants' probability estimates of finding a counter example and their selections. Experiment 1 used everyday categories in the context of a scenario to determine whether or not the number of instances in a category affected the estimated probability of a counter-example. Experiment 2 modified the scenario in order to alter participants' estimates of finding a specific counter-example. Unlike Kirby 1994a, but consistent with his proposals, both studies (...) showed that probability estimates significantly predicted selection. Overall results point to the value of understanding selections in terms of their subjective expected utility. (shrink)

In his commentary, Oaksford makes two main claims: (1) that the externalisation method used by Green, Over, and Pyne (1997) enforces the correlation observed between probability estimates and selection, and (2) that these estimates support the prediction of a downward revision of P(p) when P(p) > P(q). In this reply, we rebut claim 1 by describing the instructions more comprehensively, and claim 2 by reiterating the importance of making certain theoretical distinctions which Oaksford does not make. Our interest is (...) the psychological process of reaching decision: externalisation methods provide a means of exploring this process and of assessing the value of Bayesian approaches. (shrink)

Psychological research on people’s understanding of natural language connectives has traditionally used truth table tasks, in which participants evaluate the truth or falsity of a compound sentence given the truth or falsity of its components in the framework of propositional logic. One perplexing result concerned the indicative conditional if A then C which was often evaluated as true when A and C are true, false when A is true and C is false but irrelevant“ (devoid of value) when A is (...) false (whatever the value of C). This was called the “psychological defective table of the conditional.” Here we show that far from being anomalous the “defective” table pattern reveals a coherent semantics for the basic connectives of natural language in a trivalent framework. This was done by establishing participants’ truth tables for negation, conjunction, disjunction, conditional, and biconditional, when they were presented with statements that could be certainly true, certainly false, or neither. We review systems of three-valued tables from logic, linguistics, foundations of quantum mechanics, philosophical logic, and artificial intelligence, to see whether one of these systems adequately describes people’s interpretations of natural language connectives. We find that de Finetti’s (1936/1995) three-valued system is the best approximation to participants’ truth tables. (shrink)

This study examines the way ethical decisions are made in controversial cases at The Courier-Journal in Louisville, Kentucky, to see if codes of ethics can be efective at a newspaper known for its commitment to ethics. The study concludes that a code is efective in that environment especially on conflict-of-interest questions. A critical factor in the code's efectiveness is an ethical culture in which editors support ethical standards vigorously and foster a process that encourages newsroom debate over controversial cases.

The week, twenty-five years ago, of the Apollo spacecraft's return visit to the moon was described by Richard Nixon as the greatest since the Creation. Across the Atlantic, a French Academician judged the same event to matter less than the discovery of a lost etching by Daumier. Attitudes to technological achievement, then, differ. And they always have. Chuang-Tzu, over 2,000 years ago, relates an exchange between a Confucian passer-by and a Taoist gardener watering vegetables with a bucket drawn from (...) a well. ‘Don't you know that there is a machine with which 100 beds are easily watered in a day?’—‘How does it work?’—‘It's a counterbalanced ladle’—‘too clever to be good … all machines have to do with formulae, artificiality [which] destroy native ingenuity … and prevent the Tao from residing peacefully in one's heart’. ‘Engines of mischief, in the words of the Luddite song, or testaments to ‘the nobility of man [as] the conqueror of matter’, in those of Primo Levi, the products of technology continue to inspire phobia and philia. (shrink)

The week, twenty-five years ago, of the Apollo spacecraft's return visit to the moon was described by Richard Nixon as the greatest since the Creation. Across the Atlantic, a French Academician judged the same event to matter less than the discovery of a lost etching by Daumier. Attitudes to technological achievement, then, differ. And they always have. Chuang-Tzu, over 2,000 years ago, relates an exchange between a Confucian passer-by and a Taoist gardener watering vegetables with a bucket drawn from (...) a well. ‘Don't you know that there is a machine with which 100 beds are easily watered in a day?’—‘How does it work?’—‘It's a counterbalanced ladle’—‘too clever to be good … all machines have to do with formulae, artificiality [which] destroy native ingenuity … and prevent the Tao from residing peacefully in one's heart’. ‘Engines of mischief, in the words of the Luddite song, or testaments to ‘the nobility of man [as] the conqueror of matter’, in those of Primo Levi, the products of technology continue to inspire phobia and philia. (shrink)

We review the major phenomena of skilled typing and propose a model for the control of the hands and fingers during typing. The model is based upon an Activation‐Trigger‐Schema system in which a hierarchical structure of schemata directs the selection of the letters to be typed and, then, controls the hand and finger movements by a cooperative, relaxation algorithm. The interactions of the patterns of activation and inhibition among the schemata determine the temporal ordering for launching the keystrokes. To account (...) for the phenomena of doubling errors, the model has only “type” schemata—no “token” schemata—with only a weak binding between the special schema that signals a doubling, and its argument. The model exists as a working computer simulation and produces an output display of the hands and fingers moving over the keyboard. It reproduces some of the major phenomena of typing, including the interkeystroke interval times, the pattern of transposition errors found in skilled typists, and doubling errors. Although the model is clearly inadequate or wrong in some of its features and assumptions, it serves as a useful first approximation for the understanding of skilled typing. (shrink)

We analyze selected iterated conditionals in the framework of conditional random quantities. We point out that it is instructive to examine Lewis's triviality result, which shows the conditions a conditional must satisfy for its probability to be the conditional probability. In our approach, however, we avoid triviality because the import-export principle is invalid. We then analyze an example of reasoning under partial knowledge where, given a conditional if A then Cas information, the probability of A should intuitively increase. We explain (...) this intuition by making some implicit background information explicit. We consider several iterated conditionals, which allow us to formalize different kinds of latent information. We verify that for these iterated conditionals the prevision is greater than or equal to the probability of A. We also investigate the lower and upper bounds of the Affirmation of the Consequent inference. We conclude our study with some remarks on the supposed "independence" of two conditionals, and we interpret this property as uncorrelation between two random quantities. 2020 Elsevier Inc. All rights reserved. (shrink)

Iterated conditionals of the form If p, then if q, r are an important topic in philosophical logic. In recent years, psychologists have gained much knowledge about how people understand simple conditionals, but there are virtually no published psychological studies of iterated conditionals. This paper presents experimental evidence from a study comparing the iterated form, If p, then if q, r with the “imported,” noniterated form, If p and q, then r, using a probability evaluation task and a truth‐table task, (...) and taking into account qualitative individual differences. This allows us to critically contrast philosophical and psychological approaches that make diverging predictions regarding the interpretation of these forms. The results strongly support the probabilistic Adams conditional and the “new paradigm” that takes this conditional as a starting point. (shrink)

This second edition of Historical Dictionary of Schopenhauer's Philosophy contains a chronology, an introduction, an appendix, and an extensive bibliography. The dictionary section has over 300 cross-referenced entries on all of Schopenhauer’s books, significant philosophical ideas and concepts.

For the inaugural Workshop on Philosophy & Engineering (WPE-2007), this abstract asks why engineers are turning now to philosophy. Upon reflection, philosophy and engineering are very different occupations, and engineering has rarely turned to philosophy in the long history of the systematic design and production of complex artifacts. After briefly examining events since World War 2, the extended abstract carries over Kuhn's explanation of the rise of philosophy of science during the intellectual tumult of relativity and quantum physics in (...) the opening moments of the 20th century to the case of engineering in the early moments of the 21st century. Specifically, the paper argues that the crisis of the rapid pace of technological change, reflected in the centripetal forces of the O's (bio, nano, and info) may help explain increased interest in a philosophy of engineering at this time. The abstract concludes by citing a number of ways that philosophy may help clarify what otherwise might be confusing times. (shrink)

Iterated conditionals of the form If p, then if q, r are an important topic in philosophical logic. In recent years, psychologists have gained much knowledge about how people understand simple conditionals, but there are virtually no published psychological studies of iterated conditionals. This paper presents experimental evidence from a study comparing the iterated form, If p, then if q, r with the “imported,” noniterated form, If p and q, then r, using a probability evaluation task and a truth-table task, (...) and taking into account qualitative individual differences. This allows us to critically contrast philosophical and psychological approaches that make diverging predictions regarding the interpretation of these forms. The results strongly support the probabilistic Adams conditional and the “new paradigm” that takes this conditional as a starting point. (shrink)

Studies of categorical induction typically examine how belief in a premise (e.g., Falcons have an ulnar artery) projects on to a conclusion (e.g., Robins have an ulnar artery). We study induction in cases in which the premise is uncertain (e.g., There is an 80% chance that falcons have an ulnar artery). Jeffrey's rule is a normative model for updating beliefs in the face of uncertain evidence. In three studies we tested the descriptive validity of Jeffrey's rule and a related probability (...) theorem, the rule of total probability. Although these rules provided good approximations to mean judgments in some cases, the results from regression and correlation analyses suggest that participants focus on the parts of these rules that are associated with the highest overall probability. We relate our findings to rational models of judgment. (shrink)

M. Oaksford and N. Chater presented a Bayesian analysis of the Wason selection task in which they proposed that people choose cards in order to maximize expected information gain as measured by reduction in uncertainty in the Shannon-Weaver information theory sense. It is argued that the EIG measure is both psychologically implausible and normatively inadequate as a measure of epistemic utility. The article is also concerned with the descriptive account of findings in the selection task literature offered by Oaksford and (...) Chater. First, it is shown that their analysis data reported in the recent article of K. N. Kirby is unsound; second, an EIG analysis is presented of the experiments of P. Pollard and J. St. B. T. Evans that provides a strong empirical disconfirmation of the theory. (shrink)

The current literature on indeterminacy centers around two projects. One concerns the logic of indeterminacy; the other concerns its nature or source. The aim of this paper is to introduce, motivate and go some way toward addressing a new, third project: that of providing what I call a minimal characterization of indeterminacy. An MC, to a first approximation, is a relatively pre-theoretical characterization of indeterminacy that is neutral between the various substantive theories of the nature and logic of indeterminacy. An (...) MC thus captures a generic sense of indeterminacy that, at least in principle, is recognized by all parties to the debate over the phenomenon’s underlying nature and logic. I begin by introducing the concept of an MC and outlining some of the main theoretical virtues of providing an MC. I then establish some desiderata on a suitable MC, and use these desiderata to rule out various initially attractive proposals. In the final part of the paper I sketch the beginnings of my own MC and defend it against objections. (shrink)

We are reporting on how involved the mentor was in promoting responsible research in cases of research misconduct. We reviewed the USPHS misconduct files of the Office of Research Integrity. These files are created by Institutions who prosecute a case of possible research misconduct; ORI has oversight review of these investigations. We explored the role of the mentor in the cases of trainee research misconduct on three specific behaviors that we believe mentors should perform with their trainee: (1) review source (...) data, (2) teach specific research standards and (3) minimize stressful work situations. We found that almost three quarters of the mentors had not reviewed the source data and two thirds had not set standards. These two behaviors are positively correlated. We did not see convincing evidence in the records that mentors were causing stress, but it was apparent in the convicted trainees’ confessions that over 50% experienced some kind of stress. Secondary data, while not created for this research purpose, allows us to look at concrete research behaviors that are otherwise not very researchable. We believe it is important for mentors and institutions to devote more attention to teaching mentors about the process of education and their responsibilities in educating the next generation of scientists. This becomes a critical issue for large research groups who need to determine who is in charge educating, supervising and assuring data integrity. (shrink)

This paper focuses on Mary Midgley's influential discussions, over more than thirty years, of the relationship between human beings and animals, in particular on her concern to ‘remove the barriers’ that stand in the way of proper understanding and treatment of animals. These barriers, she demonstrates, have been erected by animal science, epistemology and mainstream moral philosophy alike. In each case, she argues, our attitudes to animals are warped by approaches that are at once excessively abstract, over-theoretical and (...) guilty of a collective hubris on the part of humankind. In keeping with Midgley's own position, it is argued in this paper that, to remove these barriers, what is required is not yet another theory of how and why animals matter, but attention to actual engagements with animals and to the moral failings or vices that distort people's relationships with them. (shrink)

The ninth-century treatises Musica and Scolica Enchiriadis are the first musical writings in the West to present a theory of organum, a mode of plainchant performance that is the earliest known form of Western medieval polyphony. The fundamental principle of this theory is that the intervallic relationship between the simultaneous melodic lines be one of "consonance" . Nevertheless, intervals arise between the voice-parts that are not symphoniae; the theory responds to this, not by explicitly invoking the concept of dissonance, but (...) by excluding these non-symphonic or non-consonant intervals from the concept of "organum." Through close analysis of the relevant texts, the dissertation seeks to explicate this concept of organum as symphonia in terms of a "metaphysics of consonance" that the Enchiriadis theorists took over from the most influential of the musical writings of late Antiquity, the De institutione musica of Boethius. ;The metaphysics of consonance projected therein is a particular development of the Pythagorean-Platonic conception of music, in which the symphoniae, because of their simple numerical ratios, represent the universal, divinely ordained rational principles of cosmic order and harmony. After a section devoted to showing that such "speculative" ideas about music formed the basis of the "practical" theory of the Enchiriadis treatises, the dissertation goes on in Part II to find that the relationship between consonance and dissonance in the Boethius Musica is structured as an unequal, hierarchized opposition, in which consonance holds the dominant position in particular because of its virtual identification with the metaphysical ideal of unity. Conversely dissonance, the opposed term of the hierarchy, represents the negative values of duality and difference, and hence discord, conflict, and disorder. Consequently, through various textual strategies, consonance is identified with "music" itself, while dissonance is effectively excluded from that domain. ;The concept of organum in the Enchiriadis treatises is found to be determined by this same metaphysics of consonance, with its consequent tendency to exclude or marginalize dissonance, a conceptual pattern that has resonated throughout the subsequent history of polyphonic theory and practice in the West. (shrink)