We intend to put into question two fundamental principles adopted by critical rationalism. One of them, explicitly proposed by Popper, argues that what is valid in logic is also in psychology. And the other, tacitly espoused, implies that epistemological verdicts have metascientific authority and validity. Regarding the second, we hold the view that to the conclusions arrived at by epistemology should not automatically be conferred metascientific authority and validity. To acquire metascientific import such conclusions also need to be derived from (...) the observation of the actual ways of producing scientific knowledge. The Hume-dependent manner with which Popper rejects induction exemplifies with emblematic strength the tendency to extend the conclusions of epistemology to philosophy of science. On one hand Popper endorses Hume’s argument about the lack of epistemic justification for induction, on the other, disagrees with the humean view that induction is routinely employed and should, therefore, be seen as a human or animal fact. Popper departs from Hume to argue that induction is not even a way of thinking; therefore, it can be employed neither by the layman nor by the scientist. Also in defense of the thesis that induction does not exist, Popper gives primacy to epistemology. More than an epistemological thesis, the theory that decrees that induction is not even a psychological fact requires empirical confirmation. For Popper being right, it is necessary to verify the theory that our minds always operate according to the model from the top down. And psychology not even provides the corroboration of Popper’s thesis. (shrink)

The dissertation has two parts, each dealing with a problem, namely: 1) What is the most adequate account of fuzziness -the so-called phenomenon of vagueness?, and 2) what is the most plausible solution to the sorites, or heap paradox? I will try to show that fuzzy properties are those which are gradual, amenable to be possessed in a greater or smaller extent. Acknowledgement of degrees in the instantiation of a property allows for a gradual transition from one opposite to the (...) other, each intermediate stage constituting an overlap in certain proportion of both contraries. Hence, degrees in the possession of a property give rise to simple contradictions. The reason why I have chosen those two questions is that they provide the main philosophical motivation for a particular brand of an infinite valued and paraconsistent logic. I will claim that Classical logic (CL) is not adequate to handle fuzzy situations, and, being deficient, is in need of being expanded to make room for degrees of truth and weak contradictions. One can hardly deny the importance of the debate, since what is ultimately at stake is what the limits of truth, rationality, intelligibility and possibility are. The main disciplines within which the research moves are the philosophy of language, philosophy of logic, and ontology. (shrink)

Charles Clark; Why Teachers Need Philosophy, Journal of Philosophy of Education, Volume 23, Issue 2, 30 May 2006, Pages 241–252, https://doi.org/10.1111/j.1467-.

Words have meaning. Sentences also have meaning, but their meaning is different in kind from any collection of the meanings of the words they contain. I discuss two puzzles related to this difference. The first is how the meanings of the parts of a sentence combine to give rise to a unified sentential meaning, as opposed to a mere collection of disparate meanings (UP1). The second is why the formal ontology of linguistic meaning changes when grammatical structure is built up (...) (UP2). For example, the meaning of a sentence is a proposition evaluable for truth and falsity. In contrast, a collection of the meanings of its parts does not constitute a proposition and is not evaluable for truth. These two puzzles are closely related, since change in formal ontology is the clearest sign of the unity of meaning. The most popular strategy for answering them is taking the meanings of the parts as abstractions from primitive sentence meanings. However, I argue that, given plausible psychological constraints, sentence meanings cannot be taken as explanatory primitives. Drawing on recent work in Generative Grammar and its philosophy, I suggest that the key to both unity questions is to distinguish strictly between lexical and grammatical meaning. The latter is irreducible and determines how lexical content is used in referential acts. I argue that these referential properties determine a formal ontology, which explains why and how formal ontology changes when grammatical structure is built up (UP2). As for UP1, I suggest that, strictly speaking, lexical meanings never combine. Instead, whenever grammar specifies a formal ontology for the lexical meanings entering a grammatical derivation, further lexical (or phrasal) meanings can only specify aspects of this recursive grammatical process. In this way, contemporary grammatical theory can be used to address old philosophical problems. (shrink)

The paper presents a comparison of the theories of truth, and the solutions of the liar paradox, proposed by Thomas Bradwardine , Jean Buridan , and Alfred Tarski.

In this paper, I suggest an approach to the alleged problem with the Tarskian formal definition of truth: its enumerative character seems to make it unable to capture our pretheoretic general understanding of truth. For this purpose, after spelling out two requirements for extending an enumerative definition to new cases, I examine to what extent Tarski's Convention T provides what are needed for extending the Tarski's enumerative definition. I conclude that, though not explicitly providing what are needed, Convention T does (...) implicitly suggest something quite promising and provide necessary conceptual resources for its further modifications. Then I suggest a Tarskian explicitly general definition of what it is to be a truth-definition on the basis of some theoretical and conceptual resources within Tarski's semantic theory, and I explain how it would make the Tarskian seemingly enumerative formal definition have a general character in accord with our pretheoretic understanding of truth. Finally, I examine the current proposal in comparison with Davidson's approach and in the light of Hintikka's new perspective. (shrink)

The book is addressed to all readers interested in cognitive science, and especially in research combining a logical analysis with psychological, linguistic and neurobiological approaches. The publication is the result of a collaboration between the Department of Cognitive Science at University of Lodz and the Department of Cognitive Science at Lund University. It is intended to provide a comprehensive presentation of the key research issues undertaken in both Departments, including considerations on meaning, natural language and reasoning, linguistic as well as (...) numerical competence, the theory of decision making, modelling of conceptual representations, cognitive and game theoretic approach to social interactions. (shrink)

Social externalism is a thesis about the individuation-conditions of thoughts. Actually, the thesis applies only to a special category of ‘trained’ thoughts, thoughts which issue from trained thinking. It isn't that the thinker of such a thought has to have had special training about the subject-matter. It is rather that he or she needs to have acquired certain basic linguistic skills and values. For trained thoughts are thoughts whose contents are tailored to the demands of communication. Social externalism, as I (...) understand it, says that people who are competent in a public language are equipped to have certain thoughts whose contents are fixed by the lexical semantic norms of their language. (shrink)

As far as ‘modern’ logical theories of vagueness are concerned, a main distinction can be drawn between ‘semantical’ ones and ‘pragmatical’ ones. The latter are defended here, because they tend to retake into account important contextual dimensions of the problem abandoned by the former. Their inchoate condition seems not alarming, since they are of surprisingly recent date. This, however, could very well be an accidental explanation. That is, the true reason for it might sooner or later turn out to be (...) bearing exactly on the fundamental human limitations, when it comes to theorizing, that these approaches are urging us to appreciate. (shrink)

Inference is a process by which appropriate belief states get connected. Belief states are biological states in the sense that they are reentrant loops ; their intrinsic feature is recognition. In inference or reasoning the transition process between belief states is regulated by the rule of concept usage, involved in the belief state, in natural language. Like belief states experiential states are also biological states whose extrinsic feature is recognition, such that, one can have an, say, X-type experience without recognizing (...) it as an experience of X. One can, however, also have an experience of an X; in the latter case, one not only has an X-type experience but also recognizes an X as an X. In some cases the transition from X-type experience to believing an X to be there instantiates a quasi-inferential pattern. In all such cases the transition process is regulated by the rule of X usage. In such quasi-inferential transition additional belief states are involved. Such states assert that there are no countervailing factors and there are additional factors conducive to the conclusion. Such belief states are expressed non-propositionally in the language of thought. Propositions are a necessary part of such quasi-inference for they give content to thoughts to which one can assign 'falsity' and defeasible reasoning requires us to assign 'falsity' to our thoughts. Propositions implicated in the quasi-inferences from experience types to belief states are the evidential reasons for the conclusion and they can only be accepted as provisionally true and have to be revised in the light of further information. (shrink)