Science advances by means of argument and debate. Based on a formal model of complex argumentation, this article assesses the interplay between evidential and inferential drivers in scientific controversy, and explains, in particular, why both evidence accumulation and argumentation are veritistically valuable. By improving the conditions for applying veritistic indicators , novel evidence and arguments allow us to distinguish true from false hypotheses more reliably. Because such veritistic indicators also underpin inductive reasoning, evidence accumulation and argumentation enhance the reliability of (...) inductive inference, for example, inference to the best explanation. 1 Introduction2 Theory of Dialectical Structures3 Debate Simulations4 From Evidence and Arguments to Truth: The First Route5 From Evidence to Truth: The Second Route6 Conclusion. (shrink)

Kiesewetter defends the normativity of rationality by presenting a new solution to the problems that arise from the common assumption that we ought to be rational. He provides a defence of a reason-response conception of rationality, an evidence-relative account of reason, and an explanation of structural irrationality in relation to these accounts.

Many epistemologists endorse a view I call “evidence essentialism:” if e is evidence of h, for some agent at some time, then necessarily, e is evidence of h, for any agent at any time. I argue that such a view is only plausible if we ignore cognitive diversity among epistemic agents, i.e., the fact that different agents have different—sometimes radically different—cognitive skills, abilities, and proclivities. Instead, cognitive diversity shows that evidential relations are contingent and relative to cognizers. This is especially (...) obvious in extreme cases and in connection with epistemic defeat, but it is also very plausibly true of ordinary agents, and regarding prima facie justification. (shrink)

There are three theories of luck in the literature, each of which tends to appeal to philosophers pursuing different concerns. These are the probability, modal, and control views. I will argue that all three theories are irreparably defective; not only are there counterexamples to each of the three theories of luck, but there are three previously undiscussed classes of counterexamples against them. These are the problems of lucky necessities, skillful luck, and diachronic luck. I conclude that a serious reevaluation of (...) the role of luck in philosophy is called for. (shrink)

Both I and Belnap, motivated the "Belnap-Dunn 4-valued Logic" by talk of the reasoner being simply "told true" (T) and simply "told false" (F), which leaves the options of being neither "told true" nor "told false" (N), and being both "told true" and "told false" (B). Belnap motivated these notions by consideration of unstructured databases that allow for negative information as well as positive information (even when they conflict). We now experience this on a daily basis with the Web. But (...) the 4-valued logic is deductive in nature, and its matrix is discrete: there are just four values. In this paper I investigate embedding the 4-valued logic into a context of probability. Jøsang's Subjective Logic introduced uncertainty to allow for degrees of belief, disbelief, and uncertainty. We extend this so as to allow for two kinds of uncertainty— that in which the reasoner has too little information (ignorance) and that in which the reasoner has too much information (conflicted). Jøsang's "Opinion Triangle" becomes an "Opinion Tetrahedron" and the 4-values can be seen as its vertices. I make/prove various observations concerning the relation of non-classical "probability" to non-classical logic. (shrink)