The epistemological debate about radical skepticism has focused on whether our beliefs in apparently obvious claims, such as the claim that we have hands, amount to knowledge. Arguably, however, our concept of knowledge is only one of many knowledge-like concepts that there are. If this is correct, it follows that even if our beliefs satisfy our concept of knowledge, there are many other relevantly similar concepts that they fail to satisfy. And this might give us pause. After all, we might (...) wonder: What is so great about the concept of knowledge that we happen to have? Might it be more important, epistemically speaking, to investigate whether our beliefs satisfy some other relevantly similar concept instead? And how should questions such as these even be understood? This paper discusses the epistemological significance of these issues. In particular, a novel skeptical stance called ‘meta-skepticism’ is introduced, which is a kind of skepticism about the idea that some knowledge-like concepts are epistemically more important than others. It suggested that it is unclear whether this form of skepticism can be avoided. (shrink)

On a simple and neat view, sometimes called the Relational Analysis of Attitude Ascriptions, a belief ascription on the form ‘S believes that x is F’ is correct if, and only if, S stands in the belief-relation to the proposition designated by ‘that x is F’, i.e., the proposition that x is F. It follows from this view that, for a person to believe, say, that x is a boat, there is one unique proposition that she has to believe. This (...) paper argues against this view. It fails, I contend, to make sense of peripheral concept variation. As we attribute and individuate concepts, two people’s concepts C1 and C2 count as e.g., concepts of boats even if their concepts have different extensions in peripheral, or borderline, cases of boats. Thus, A and B can believe that x is a boat through believing peripherally different propositions. It follows that there is no unique proposition that a person has to believe in order to believe e.g., that x is a boat. (shrink)

This thesis focuses on models of conceptual change in science and philosophy. In particular, I developed a new bootstrapping methodology for studying conceptual change, centered around the formalization of several popular models of conceptual change and the collective assessment of their improved formal versions via nine evaluative dimensions. Among the models of conceptual change treated in the thesis are Carnap’s explication, Lakatos’ concept-stretching, Toulmin’s conceptual populations, Waismann’s open texture, Mark Wilson’s patches and facades, Sneed’s structuralism, and Paul Thagard’s conceptual revolutions. (...) -/- In order to analyze and compare the conception of conceptual change provided by these different models, I rely on several historical reconstructions of episodes of scientific conceptual change. The historical episodes of scientific change that figure in this work include the emergence of the morphological concept of fish in biological taxonomies, the development of scientific conceptions of temperature, the Church-Turing thesis and related axiomatizations of effective calculability, the history of the concept of polyhedron in 17th and 18th century mathematics, Hamilton’s invention of the quaternions, the history of the pre-abstract group concepts in 18th and 19th century mathematics, the expansion of Newtonian mechanics to viscous fluids forces phenomena, and the chemical revolution. I will also present five different formal and informal improvements of four specific models of conceptual change. I will first present two different improvements of Carnapian explication, a formal and an informal one. My informal improvement of Carnapian explication will consist of a more fine-grained version of the procedure that adds an intermediate, third step to the two steps of Carnapian explication. I will show how this novel three-step version of explication is more suitable than its traditional two-step relative to handle complex cases of explications. My second, formal improvement of Carnapian explication will be a full explication of the concept of explication itself within the theory of conceptual spaces. By virtue of this formal improvement, the whole procedure of explication together with its application procedures and its pragmatic desiderata will be reconceptualized as a precise procedure involving topological and geometrical constraints inside the theory of conceptual spaces. My third improved model of conceptual change will consist of a formal explication of Darwinian models of conceptual change that will make vast use of Godfrey-Smith’s population-based Darwinism for targeting explicitly mathematical conceptual change. My fourth improvement will be dedicated instead to Wilson’s indeterminate model of conceptual change. I will show how Wilson’s very informal framework can be explicated within a modified version of the structuralist model-theoretic reconstructions of scientific theories. Finally, the fifth improved model of conceptual change will be a belief-revision-like logical framework that reconstructs Thagard’s model of conceptual revolution as specific revision and contraction operations that work on conceptual structures. -/- At the end of this work, a general conception of conceptual change in science and philosophy emerges, thanks to the combined action of the three layers of my methodology. This conception takes conceptual change to be a multi-faceted phenomenon centered around the dynamics of groups of concepts. According to this conception, concepts are best reconstructed as plastic and inter-subjective entities equipped with a non-trivial internal structure and subject to a certain degree of localized holism. Furthermore, conceptual dynamics can be judged from a weakly normative perspective, bound to be dependent on shared values and goals. Conceptual change is then best understood, according to this conception, as a ubiquitous phenomenon underlying all of our intellectual activities, from science to ordinary linguistic practices. As such, conceptual change does not pose any particular problem to value-laden notions of scientific progress, objectivity, and realism. At the same time, this conception prompts all our concept-driven intellectual activities, including philosophical and metaphilosophical reflections, to take into serious consideration the phenomenon of conceptual change. An important consequence of this conception, and of the analysis that generated it, is in fact that an adequate understanding of the dynamics of philosophical concepts is a prerequisite for analytic philosophy to develop a realistic and non-idealized depiction of itself and its activities. (shrink)

The conservative idea that it is a philosopher’s job to clarify common sense beliefs about ordinary concepts is being weeded out from the population and replaced by a revisionist agenda: philosophers should not merely describe but also analyze and suggest ways to improve our concepts. This project is called "conceptual engineering." The conceptual engineering literature is growing rapidly as more philosophers undertake normative conceptual work. However, many philosophers are practicing conceptual engineering untethered to an explicit methodology. Analyses addressing how we (...) should engineer a concept and what should be considered successful are scarce. The thesis of this dissertation is that Carnapian Explication solves this methodological deficiency. (shrink)