According to proponents of relational direct realism, veridical perceptual experiences are irreducibly relational mental states that include as constituents perceived physical objects or intrinsic aspects of them. One consequence of the theory is the rejection of the causal theory of perception. This paper defends the relational theory against several objections recently developed by Paul Coates. He argues that the required experiential relation is incoherent and unmotivated. The argument that it is incoherent commits a fallacy. In reply to the argument that (...) it is unmotivated, I suggest that the relational theorist's appeal to transparency provides sufficient motive and, when properly clarified, defeasibly justifies the theory as well. Coates also argues that rejection of the causal theory leaves relational theorists without any way of determining which object is perceived or of accommodating our scientific understanding of perceptual experiences as causally dependent on physical objects. I reply that relational theorists are able to provide the required explanations and discuss how the relational theory is consistent with this scientific understanding of perceptual experience. (shrink)

In a recent paper, Jeanne Peijnenburg and David Atkinson [ Studia Logica, 89:333-341 ] have challenged the foundationalist rejection of infinitism by giving an example of an infinite, yet explicitly solvable regress of probabilistic justification. So far, however, there has been no criterion for the consistency of infinite probabilistic regresses, and in particular, foundationalists might still question the consistency of the solvable regress proposed by Peijnenburg and Atkinson.

Coherence is a key concept in many accounts of epistemic justification within ‘traditional’ analytic epistemology. Within formal epistemology, too, there is a substantial body of research on coherence measures. However, there has been surprisingly little interaction between the two bodies of literature. The reason is that the existing formal literature on coherence measure operates with a notion of belief system that is very different from—what we argue is—a natural Bayesian formalisation of the concept of belief system from traditional epistemology. Therefore, (...) formal epistemology has so far only been concerned with one particular—arguably not even very natural—way of formalising coherence of belief systems; it has by no means refuted the viability of coherentism. In contrast to the existing literature, we formalise belief systems as families of assignments of (conditional) degrees of belief (which may be compatible with several subjective probability measures). Within this framework, we propose a Bayesian formalisation of the thrust of BonJour’s coherence concept in The structure of empirical knowledge (Harvard University Press, Cambridge, 1985), using a combination of Bayesian confirmation theory and basic graph theory. In excursions, we introduce graded notions for both logical and probabilistic consistency of belief systems—the latter being based on certain geometrical structures induced by probabilistic belief systems. For illustration, we reconsider BonJour’s “ravens” challenge (op. cit., p. 95f.). Finally, potential objections to our proposed formal coherence notion are explored. (shrink)

While there is no shortage of philosophical literature discussing knowledge by acquaintance, there is a surprising dearth of work about theories of epistemic justification based on direct acquaintance. This paper explores a basic framework for a thoroughly general account of epistemic justification by acquaintance. I argue that this approach to epistemic justification satisfies two importance aspects of justification. After sketching how the acquaintance approach can meet both objective and subjective aspects for epistemic justification, I will outline how this general account (...) of justification by acquaintance can be applied to the analysis of justification for many types of beliefs. Finally, some of the objections to the acquaintance approach will be considered and answered. (shrink)