Classical logic is explosive in the face of contradiction, yet we find ourselves using inconsistent theories. Mark Colyvan, one of the prominent advocates of the indispensability argument for realism about mathematical objects, suggests that such use can be garnered to develop an argument for commitment to inconsistent objects and, because of that, a paraconsistent underlying logic. I argue to the contrary that it is open to a classical logician to make distinctions, also needed by the paraconsistent logician, which allow a (...) more nuanced ranking of theories in which inconsistent theories can have different degrees of usefulness and productivity. Facing inconsistency does not force us to adopt an underlying paraconsistent logic. Moreover we will see that the argument to best explanation deployed by Colyvan in this context is unsuccessful. I suggest that Quinean approach which Colyvan champions will not lead to the revolutionary doctrines Colyvan endorses. (shrink)

It's widely supposed that unification is an epistemic virtue: the degree to which a theory is unified contributes to its overall confirmation. However, this supposition has consequences which haven't been noted, and which undermine the leading accounts of unification. For, given Hempel's equivalence condition, any epistemic virtue must be such that logically equivalent theories must equally well unify any body of evidence, and logically equivalent bodies of evidence must be equally well unified by any theory. Yet the leading accounts of (...) unification in Bayesian terms, or those in terms of argument patterns, cannot satisfy these constraints conditions. The reason for this runs deep: these accounts of unification make unity depend on factors that vary between equivalent theories: the probabilistic relations of their components, or their relations to argument patterns. The solution is to abandon such accounts and instead adopt an account of unity based on worldly relations such as causation, rather than inferential relations. Such an account effortlessly satisfies the equivalence conditions, and so may describe the epistemic virtue of unity. (shrink)

Die folgenden Ausführungen enthalten einen Beitrag zum Problem der Induktion. Den bisher bekannt gewordenen Interpretationen induktiver Regeln wird eine weitere zur Seite gestellt. Sie beruht auf der von Popper propagierten Idee der Annäherung an die Wahrheit, genauer: auf einer geeigneten topologischen Präzisierung dieser Annäherungsidee. Wie sich dabei herausstellt, ist die approximationstheoretische Deutung der allgemeinen Induktion zwar stringent, aber nicht induktivistisch, d.h. sie liefert keine irgendwie geartete Rechtfertigung induktiver Regeln.

The importance for realism of the concept of truthlikeness was first stressed by Popper. Popper himself not only mapped out a program for defining truthlikeness (in terms of falsity content and truth content) but produced the first definitions within this program. These were shown to be inadequate. But the program lingered on, and the most recent attempt to revive it is that of Newton-Smith. His attempt is a failure, not because of some minor defect or technical flaw in his particular (...) account but rather because the program incorporates a fundamental flaw. However, realists need not despair. There already exists an entirely different program not subject to these criticisms. (shrink)

Le présent article veut (1) montrer que la théorie qualitative de la vérisimilarité exposée par Karl R. Popper dansConjectures and RefutationsetObjective Knowledgeest compatible avec sa méthode des conjectures, corroborations et réfutations; (2) faire voir pourquoi cette théorie apparaît néanmoins trop forte d'un point de vue intuitif; (3) montrer comment le système poppérien permet de contourner la preuve formelle présentée par Pavel Tichy en 1974 à l'encontre de la théorie qualitative de la vérisimilarité; (4) proposer une nouvelle définition de la vérisimilarité (...) qui apparaisse non seulement logiquement fondée, mais plus intuitivement acceptable et davantage liée à la méthodologie poppérienne que la définition originelle. (shrink)

Some of the problem areas in which British philosophers of science have recently been engaged are described and some of the major contributions noted. Two sets of problems are given special attention: one concerned with the analysis of probability statements and one concerned with the appraisal of scientific theories. Three traditions in the approach to this second set of problems are distinguished. These might be called the Carnapian, the Popperian and the Wittgensteinian traditions.