scholarly journals Paradoxes and Inconsistent Mathematics

2021 ◽  
Author(s):  
Zach Weber

Logical paradoxes – like the Liar, Russell's, and the Sorites – are notorious. But in Paradoxes and Inconsistent Mathematics, it is argued that they are only the noisiest of many. Contradictions arise in the everyday, from the smallest points to the widest boundaries. In this book, Zach Weber uses “dialetheic paraconsistency” – a formal framework where some contradictions can be true without absurdity – as the basis for developing this idea rigorously, from mathematical foundations up. In doing so, Weber directly addresses a longstanding open question: how much standard mathematics can paraconsistency capture? The guiding focus is on a more basic question, of why there are paradoxes. Details underscore a simple philosophical claim: that paradoxes are found in the ordinary, and that is what makes them so extraordinary.

2003 ◽  
Vol 9 (1) ◽  
pp. 3-25 ◽  
Author(s):  
György Serény

The fact that Gödel's famous incompleteness theorem and the archetype of all logical paradoxes, that of the Liar, are related closely is, of course, not only well known, but is a part of the common knowledge of the community of logicians. Indeed, almost every more or less formal treatment of the theorem makes a reference to this connection. Gödel himself remarked in the paper announcing his celebrated result (cf. [7]):The analogy between this result and Richard's antinomy leaps to the eye;there is also a close relationship with the ‘liar’ antinomy, since … we are… confronted with a proposition which asserts its own unprovability.In the light of the fact that the existence of this connection is commonplace it is all the more surprising that very little can be learnt about its exact nature except perhaps that it is some kind of similarity or analogy. There is, however, a lot more to it than that. Indeed, as we shall try to show below, the general ideas underlying the three central theorems concerning internal limitations of formal deductive systems can be taken as different ways to resolve the Liar paradox. More precisely, it will turn out that an abstract formal variant of the Liar paradox, which can almost straightforwardly inferred from its original ordinary language version, is a possible common generalization of (both the syntactic and semantic versions of) Gödel's incompleteness theorem, the theorem of Tarski on the undefinability of truth, and that of Church concerning the undecidability of provability.


1979 ◽  
Vol 38 (2) ◽  
pp. 373-391 ◽  
Author(s):  
Laurence Goldstein

There can be no doubt that the existence of paradoxes has stimulated vigorous and highly productive activity in philosophy and in logic. Take two famous examples: The Liar Paradox, which arises from a sentence such asL This statement is false.and the Russell Paradox which arises from the sentenceR The class of all classes which are not members of themselvesis a member of itself.The first of these has been a source of anguish for over 2,000 years. The second has engaged the serious attention of logicians for over three quarters of a century. Investigation of paradoxes of this sort has spawned whole new fields of study, such as technical semantics and axiomatic set theory.It has been claimed that legal reasoning is infected with paradoxes and that these paradoxes are similar in structure to those, like the two we have cited, which are of interest to the logician. If this claim were true one of two consequences would follow. Either the jurisprudent would face what would in all likelihood be a protracted struggle with these legal paradoxes resulting, perhaps, in significant additions to legal theory, or else, if these paradoxes were sufficiently similar to those of the logician, he might try to utilise the logician's results to solve his own legal puzzles.The first alternative, though attractive to a theoretician, may appear rather dismal to those engaged in the business of law. Whereas reflection on the logical paradoxes can lead to only more refined abstractions—the philosopher's meat and drink—legal theory is rather intimately connected with practical affairs.


2020 ◽  
Author(s):  
Michael Lesnick ◽  
Sebastian Musslick ◽  
Biswadip Dey ◽  
Jonathan D. Cohen

This note introduces mathematical foundations for modeling of human multitask performance. Using basic definitions from set theory and graph theory, we introduce formal definitions of the environment in which multitasks are performed, of an agent which attempts to perform a multitask, and of the success rate of the agent on a multitask. Drawing on the recent literature on modeling of multitasking, we give two simple examples of multitasking agents, and illustrate the performance of these agents on two multitasking problems: the well-known Stroop task, and a more complex variant.


2021 ◽  
Author(s):  
Nicolas Spatola ◽  
Thierry Chaminade

Humanoid robots are predicted to be increasingly present in the everyday life of millions of people worldwide. Humans make sense these artificial agents’ actions mainly through the attribution of human characteristics, a process called anthropomorphism. However, despite a large number of studies, how the representation of artificial agents is constructed remains an open question. Here, we aim at integrating the process of anthropomorphism into the cognitive control theory, that postulates that we adapt resources management for information processing according to the current situation. In three experiments, we manipulated the cognitive load of participants while being observed by a humanoid robot to investigate how it could impact the online adaptation of the mental representation of the robot. The first two experiments indicated an online control of demanding resources in order to switch from an intentional to a physical representation, therefore inhibiting anthropomorphic, i.e. social, inferences. The third experiment investigated how the goals of the observing robot, i.e. “what” versus “why” is the robot observing, influences the effect of the cognitive load, showing that an explicit focus on its intentionality automatically biases cognitive processes towards anthropomorphism, yielding insights on how we mentally represent interacting robots when cognitive control theory and robots’ anthropomorphism are considered together.


Author(s):  
Roman Svetlov ◽  
Konstantin Shevtsov

The subject of the research is the question of what texts of Plato could become a stimulus for the formation of skeptical ideas in the Academy. Can we, in particular, raise the question of the presence in the texts of Plato of something similar to the principle of the “epoche”, which is the most important methodological sign of skepticism? Can be compared with skepticism the elenchic strategy of Socrates? In our opinion, there are a number of moments in the works of Plato, which brings him closer to skeptical discourse (although this does not make him a skeptic). We dwell only on two of them. The first is the ability of the protagonists of his dialogues to hold in their arguments the two opposite sides of the subject in their undoubted difference and, at the same time, in mutual necessity. This is the Platonic dialectic in its true expression, examples of which we see in the Sophistes and the Parmenides. The second specific aspect of Plato's thought is in the formulation by Plato of a number of logical paradoxes. In its classic version, it became known, however, a little later, in the works of representatives of the Megarian school. We shall deal in more detail with the paradox of the liar, or “the thesis of Epimenides”, which is often seen as a classic example of a self-referential statement. The article will show analogies to the paradox of the liar in Plato's texts. The key point is the last argument from the Theaetetus, where Socrates examines the definition of knowledge as a true opinion with the addition of a specifying attribute (Thaet 201c-208d), as well as the 7th and 8th hypotheses of the Parmenides (Parm. 164b-166c). It seems to us that this moment of the Platonic dialectic also turns out to be a definite resource for the future “skeptical turn” in the Academy. Especially in the situation when the dialogues of Plato were discussed in terms of interest in the arguments of Pyrrho and the Megarians, for whom paradoxes were one of the important methodological tools.


Author(s):  
Vsevolod Ladov

The Liar Paradox has been widely discussed from the ancient times and preserved its importance in contemporary philosophy of logic and mathematics. At the beginning of the 20th century, F.P. Ramsey asserted that the Liar Paradox is different from pure logical paradoxes such as Russell’s paradox. The Liar Paradox is connected with language and can be considered a semantic paradox. Ramsey's point of view has become widespread in the logic of the 20th century. The author of the article questions this view. It is argued that the Liar Paradox cannot be unequivocally attributed to the semantic paradoxes and therefore Ramsey's point of view should be revised.


Author(s):  
Samson Abramsky ◽  
Giovanni Carù

We establish a strong link between two apparently unrelated topics: the study of conflicting information in the formal framework of valuation algebras, and the phenomena of non-locality and contextuality. In particular, we show that these peculiar features of quantum theory are mathematically equivalent to a general notion of disagreement between information sources. This result vastly generalizes previously observed connections between contextuality, relat- ional databases, constraint satisfaction problems and logical paradoxes, and gives further proof that contextual behaviour is not a phenomenon limited to quantum physics, but pervades various domains of mathematics and computer science. The connection allows to translate theorems, methods and algorithms from one field to the other, and paves the way for the application of generic inference algorithms to study contextuality. This article is part of the theme issue ‘Contextuality and probability in quantum mechanics and beyond’.


1997 ◽  
Vol 161 ◽  
pp. 203-218 ◽  
Author(s):  
Tobias C. Owen

AbstractThe clear evidence of water erosion on the surface of Mars suggests an early climate much more clement than the present one. Using a model for the origin of inner planet atmospheres by icy planetesimal impact, it is possible to reconstruct the original volatile inventory on Mars, starting from the thin atmosphere we observe today. Evidence for cometary impact can be found in the present abundances and isotope ratios of gases in the atmosphere and in SNC meteorites. If we invoke impact erosion to account for the present excess of129Xe, we predict an early inventory equivalent to at least 7.5 bars of CO2. This reservoir of volatiles is adequate to produce a substantial greenhouse effect, provided there is some small addition of SO2(volcanoes) or reduced gases (cometary impact). Thus it seems likely that conditions on early Mars were suitable for the origin of life – biogenic elements and liquid water were present at favorable conditions of pressure and temperature. Whether life began on Mars remains an open question, receiving hints of a positive answer from recent work on one of the Martian meteorites. The implications for habitable zones around other stars include the need to have rocky planets with sufficient mass to preserve atmospheres in the face of intensive early bombardment.


GeroPsych ◽  
2018 ◽  
Vol 31 (4) ◽  
pp. 205-213 ◽  
Author(s):  
Kathryn L. Ossenfort ◽  
Derek M. Isaacowitz

Abstract. Research on age differences in media usage has shown that older adults are more likely than younger adults to select positive emotional content. Research on emotional aging has examined whether older adults also seek out positivity in the everyday situations they choose, resulting so far in mixed results. We investigated the emotional choices of different age groups using video games as a more interactive type of affect-laden stimuli. Participants made multiple selections from a group of positive and negative games. Results showed that older adults selected the more positive games, but also reported feeling worse after playing them. Results supplement the literature on positivity in situation selection as well as on older adults’ interactive media preferences.


Author(s):  
Lisa Irmen ◽  
Julia Kurovskaja

Grammatical gender has been shown to provide natural gender information about human referents. However, due to formal and conceptual differences between masculine and feminine forms, it remains an open question whether these gender categories influence the processing of person information to the same degree. Experiment 1 compared the semantic content of masculine and feminine grammatical gender by combining masculine and feminine role names with either gender congruent or incongruent referents (e.g., Dieser Lehrer [masc.]/Diese Lehrerin [fem.] ist mein Mann/meine Frau; This teacher is my husband/my wife). Participants rated sentences in terms of correctness and customariness. In Experiment 2, in addition to ratings reading times were recorded to assess processing more directly. Both experiments were run in German. Sentences with grammatically feminine role names and gender incongruent referents were rated as less correct and less customary than those with masculine forms and incongruent referents. Combining a masculine role name with an incongruent referent slowed down reading to a greater extent than combining a feminine role name with an incongruent referent. Results thus specify the differential effects of masculine and feminine grammatical gender in denoting human referents.


Sign in / Sign up

Export Citation Format

Share Document