The notion of a severe test has played an important methodological role in the history of science. But it has not until recently been analyzed in any detail. We develop a generally Bayesian analysis of the notion, compare it with Deborah Mayo’s error-statistical approach by way of sample diagnostic tests in the medical sciences, and consider various objections to both. At the core of our analysis is a distinction between evidence and confirmation or belief. These notions must be kept separate (...) if mistakes are to be avoided; combined in the right way, they provide an adequate understanding of severity. Those who think that the weight of the evidence always enables you to choose between hypotheses “ignore one of the factors (the prior probability) altogether, and treat the other (the likelihood) as though it ...meant something other than it actually does. This is the same mistake as is made by someone who has scruples about measuring the arms of a balance (having only a tape measure at his disposal ...), but is willing to assert that the heavier load will always tilt the balance (thereby implicitly assuming, although without admitting it, that the arms are of equal length!). (Bruno de Finetti, Theory of Probability)2. (shrink)

How should contractualists assess the permissibility of risky actions? Both main views on the question, ex ante and ex post, fail to distinguish between different kinds of risk. In this article, I argue that this overlooks a third alternative that I call “objective ex ante contractualism”. Objective ex ante substitutes discounting complaints by epistemic risk in favor of discounting by objective risk. I further argue in favor of this new view. Objective ex ante contractualism provides the best model of justifiability (...) to each. (shrink)

The theory of natural selection is a rich systematization of biological knowledge without a first principle. When formulations of a proposed principle of natural selection are examined carefully, each is seen to be exhaustively analyzable into a proposition about sources of fitness and a proposition about consequences of fitness. But whenever the fitness of an organic variety is well defined in a given biological situation, its sources are local contingencies together with the background of laws from disciplines other than the (...) theory of natural selection; and the consequences of fitness for the long range fate of organic varieties are essentially applications of probability theory. Hence there is no role and no need for a principle of the theory of natural selection, and any generalities that may hold in that theory are derivative rather than fundamental. (shrink)

Based on archival material from the Carnap and FeiglArchives, this paper re-examines Carnap's approach tothe issue of scientific realism in the 1950s and theearly 1960s. It focuses on Carnap's re-invention ofthe Ramsey-sentence approach to scientific theoriesand argues that Carnap wanted to entertain a genuineneutral stance in the realism-instrumentalism debate.Following Grover Maxwell, it claims that Carnap'sposition may be best understood as a version of`structural realism'. However, thus understood,Carnap's position faces the challenge that Newmanraised against Russell's structuralism: the claim thatthe knowledge of (...) the unobservable is limited to itspurely structural characteristics is eitheruninformative or unsustainable. (shrink)

There has been an empiricist tradition in the core of Logical Positivism/Empiricism, starting with Moritz Schlick and ending in Herbert Feigl (via Hans Reichenbach), according to which the world of empiricism need not be a barren place devoid of all the explanatory entities posited by scientific theories. The aim of this paper is to articulate this tradition and to explore ways in which its key elements can find a place in the contemporary debate over scientific realism. It presents a way (...) empiricism can go for scientific realism without metaphysical anxiety, by developing an indispensability argument for the adoption of the realist framework. This argument, unlike current realist arguments, has a pragmatic ring to it: there is no ultimate argument for the adoption of the realist framework. (shrink)

A. W. Carus champions Rudolf Carnap’s ideal of explication as a model for liberal political deliberation. Constructing a linguistic framework for discussing social problems, he argues, promotes the resolution of our disputes. To flesh out and assess this proposal, I examine debate about the social institutions of marriage and adoption. Against Carus, I argue that not all citizens would accept the pragmatic principles underlying Carnap’s ideal. Nevertheless, explication may facilitate inquiry in the social sciences and be used to create models (...) that help us to understand past disputes. This latter application reveals explication’s potential for refining the social histories that inform contemporary political discourse. (shrink)

Rudolf Carnap’s role in the debate over scientific realism is fairly unclear. In a certain sense, Carnap must be regarded as the one who rendered the whole issue irrelevant. However, it cannot be ignored that Carnap sometimes spoke of himself as an ‘empirical realist.’ So the question to be answered is: in what sense, if at all, did Carnap play a constructive role in the scientific realism debate. It is the aim of the present paper to tackle this question by (...) investigating the relationship between Carnap’s approach toward the realism issue, on the one hand, and the realist positions defended by his logical empiricist fellows Hans Reichenbach and Eino Kaila, on the other. It will be shown that Carnap agreed with Reichenbach that realism has essentially to do with language, but that he disagreed with him over the significance of probability in defending the scientific realist stance. My point will be that realism is not a ‘problem of language.’ Furthermore, it will be argued that Carnap was correctly criticized by Reichenbach for neglecting the role of probability in science. Nevertheless, what can be learned from Carnap’s approach toward the realism issue is that scientific realism cannot be defended in the way that Reichenbach himself suggested, namely by arguing inductively for the adequacy of the realistic ‘language form.’ Rather, scientific realism can only be defended on the ground that language itself is dependent on the ‘structure of the world.’ And this is exactly the point where, eventually, Kaila will enter the scene. (shrink)

The aim of this paper is make a contribution to the ongoing search for an adequate concept of the a priori element in scientific knowledge. The point of departure is C.I. Lewis’s account of a pragmatic a priori put forward in his "Mind and the World Order" (1929). Recently, Hasok Chang in "Contingent Transcendental Arguments for Metaphysical Principles" (2008) reconsidered Lewis’s pragmatic a priori and proposed to conceive it as the basic ingredient of the dynamics of an embodied scientific reason. (...) The present paper intends to further elaborate Chang’s account by relating it with some conceptual tools from cognitive semantics and certain ideas that first emerged in the context of the category-theoretical foundations of mathematics. (shrink)

Some philosophers, for example Quine, doubt the possibility of jointly using modalities and quantification. Simple model-theoretic considerations, however, lead to a reconciliation of quantifiers with such modal concepts as logical, physical, and ethical necessity, and suggest a general class of modalities of which these are instances. A simple axiom system, analogous to the Lewis systems S1 —S5, is considered in connection with this class of modalities. The system proves to be complete, and its class of theorems decidable.

You and I lead different lives. While we share a society and a world, our existence is separate from one another. You and I matter individually, by ourselves. My dissertation is about this simple thought. I argue that this simple insight, the separateness of persons, tells us something fundamental about morality. My dissertation seeks to answer how the separateness of persons matters. I develop a precise view of the demands of the separateness of persons. The separateness of persons imposes both (...) a requirement on the justification of first-order moral principles as well as a requirement on the content of first-order moral principles. In specifying these demands, I argue that respecting the separateness of persons requires taking into consideration each person’s point of view separately. This requires taking into account the moral relations in which individuals stand to one another. I make use of this relational understanding of the separateness of persons to advance various debates in moral and political philosophy. I argue for a framework to assess to which extent the veil of ignorance can be reconciled with the separateness of persons. I also argue for a new view on the ethics of risk which is a form of contractualism that discounts risks only by their objective risk. Furthermore, I argue for a new solution to the problem of aggregation that is skeptical of aggregation and can set plausible limits to aggregation. Lastly, I provide a new relational agent-based justification for deontological constraints. In addition to answering how the separateness of persons matters, I defend the separateness of persons against challenges. Most importantly, I argue that the importance of the separateness of persons is not undermined even if we believe that our personal identity, i.e. whether we persist as the same person, is unimportant. (shrink)