This paper explores the scope and limits of rational consensus through mutual respect, with the primary focus on the best known formal model of consensus: the Lehrer–Wagner model. We consider various arguments against the rationality of the Lehrer–Wagner model as a model of consensus about factual matters. We conclude that models such as this face problems in achieving rational consensus on disagreements about unknown factual matters, but that they hold considerable promise as models of how to rationally resolve non-factual disagreements.

Some philosophers claim that perception immediately and prima facie justifies belief in virtue of its phenomenal character (Huemer, Skepticism and the veil of perception. Rowman & Littlefield, Lanham, 2001; Pryor, There is immediate justification. In: Steup M, Sosa E (eds) Contemporary debates in epistemology. Blackwell, London (2014), pp. 181–202, 2005). To explain this special justificatory power, some appeal to perception’s presentational character: the idea that perceptual experience presents its objects as existing here-and-now (Chudnoff, Intuition. Oxford University Press, Oxford, 2013; Berghofer, (...) Husserl Stud 34(2):145–170, 2018). As some philosophers have noted, if perception justifies in virtue of its presentational character alone, the kind of content perception has should not matter for perceptual justification; more precisely, it should not matter whether perceptual content is propositional or not (e.g., Smithies, The epistemic role of consciousness. Oxford University Press, Oxford, 2019; Kriegel, Australas J Philos, 2021). However, most philosophers tend to resist this conclusion, holding that perception must be propositional in order to justify, on the ground that all our model of justification are propositional (e.g., Gauker, Philos Perspect 26(1):19–50, 2012). This paper challenges this claim. The paper consists of a negative and a positive part. In the negative part, I discuss and reject the master argument for the propositionality of perception; the conclusion is that propositional content is neither sufficient nor necessary to explain perception’s justificatory power. In the positive part, I take this conclusion seriously and outline an objectual model of perceptual justification. I define objectual attitudes as mental states whose content is not a full proposition, but a sub-propositional representational item, such as the representation of objects, properties, and kinds (Grzankowski and Montague, Non-propositional intentionality. Oxford University Press, Oxford, 2018), and show that it is plausible that some perceptions and some beliefs are attitudes of this kind. I then argue that objectual perceptual experiences have the right kind of phenomenal character and the right kind of structure to serve for immediate prima facie justification. I conclude by defending my objectual model from three objections. (shrink)

Knowledge brokers are among the main channels of communication between scientists and the public and a key element to establishing a relation of trust between the two. But translating knowledge from the scientific community to a wider audience presents several difficulties, which can be accentuated in times of crisis. In this paper we study some of the problems that knowledge brokers face when communicating in times of crisis. During the first wave of the COVID-19 pandemic, we collected interviews with Italian (...) experts that played a major role as knowledge brokers in the local media. We asked them questions about five main topics: the features and role of science communicators; the use of language in communicating science; the importance of the relation of trust with the public; the peculiarity of communicating in a context of emergency; the problem of disagreement among experts, and its public perception and communication. The goal of this paper is to understand, through the words of knowledge brokers themselves, what they consider as best practices (and obstacles) to create trust between scientists and the public. Our empirical work can inform normative accounts of what knowledge brokering should be about. (shrink)

In recent decades much literature has been produced on disagreement; the puzzling conclusion being that epistemic disagreement is, for the most part, either impossible (e.g. Aumann (Ann Stat 4(6):1236–1239, 1976)), or at least easily resolvable (e.g. Elga (Noûs 41(3):478–502, 2007)). In this paper I show that, under certain conditions, an equally puzzling result arises: that is, disagreement cannot be rationally resolved by belief updating. I suggest a solution to the puzzle which makes use of some of the principles of Hintikka’s (...) Socratic epistemology. (shrink)

Notoriously, the Einstein equations of general relativity have solutions in which closed timelike curves occur. On these curves time loops back onto itself, which has exotic consequences: for example, traveling back into one's own past becomes possible. However, in order to make time travel stories consistent constraints have to be satisfied, which prevents seemingly ordinary and plausible processes from occurring. This, and several other "unphysical" features, have motivated many authors to exclude solutions with CTCs from consideration, e.g. by conjecturing a (...) chronology protection law. In this contribution we shall investigate the nature of one particular class of exotic consequences of CTCs, namely those involving unexpected cases of indeterminism or determinism. Indeterminism arises even against the backdrop of the usual deterministic physical theories when CTCs do not cross spacelike hypersurfaces outside of a limited CTC-region|such hypersurfaces fail to be Cauchy surfaces. We shall compare this CTC-indeterminism with four other types of indeterminism that have been discussed in the philosophy of physics literature: quantum indeterminism, the indeterminism of the hole argument, non-uniqueness of solutions of differential equations and lack of predictability due to insuffcient data. By contrast, a certain kind of determinism appears to arise when an indeterministic theory is applied on a CTC: things cannot be different from what they already were. Again we shall make comparisons, this time with other cases of determination in physics. We shall argue that on further consideration both this indeterminism and determinism on CTCs turn out to possess analogues in other, familiar areas of physics. CTC- indeterminism is close to the epistemological indeterminism we know from statistical physics, while the "fixedness" typical of CTC-determinism is pervasive in physics. CTC- determinism and CTC-indeterminism therefore do not provide incontrovertible grounds for rejecting CTCs as conceptually inadmissible. (shrink)

Are probabilism and special relativity compatible? Dieks argues that they are. But the possible universe he specifies, designed to exemplify both probabilism and special relativity, either incorporates a universal “now”, or amounts to a many world universe, or fails to have any one definite overall Minkowskian-type space-time structure. Probabilism and special relativity appear to be incompatible after all. What is at issue is not whether “the flow of time” can be reconciled with special relativity, but rather whether explicitly probabilistic versions (...) of quantum theory should be rejected because of incompatibility with special relativity. (shrink)

Open peer commentary on the article “Varela’s Radical Proposal: How to Embody and Open Up Cognitive Science” by Kristian Moltke Martiny. Upshot: I examine Varela’s relationship with Husserl’s phenomenology, highlighting Varela’s acknowledgment of the pragmatic dimension of its phenomenological reduction. I argue that Varela sees, in some developments of phenomenology, a deconstruction of the subject-object duality and an embodied view of the mind. I also highlight the existential dimension of Varela’s radical proposal, which contributes to further opening up and embodying (...) cognitive science. (shrink)

Saunders' recent arguments in favour of the weak discernibility of (certain) quantum particles seem to be grounded in the 'generalist' view that science only provides general descriptions of the worlIn this paper, I introduce the ‘generalist’ perspective and consider its possible justification and philosophical basis; and then look at the notion of weak discernibility. I expand on the criticisms formulated by Hawley (2006) and Dieks and Veerstegh (2008) and explain what I take to be the basic problem: that the properties (...) invoked by Saunders cannot be pointed to as ‘individuators’ of otherwise indiscernible (and thus numerically identical) entities because their ontological status remains underdetermined by the evidence and the established interpretation of the theory. In addition to to this, I suggest that Saunders does not deal adequately with bosons, and cannot do so exactly because he subscribes to PII and the generalist picture. The last part of the paper contains a critical examination of the claim (or at least implicit assumption) that the generalist picture should be regarded as obviously compelling by the modern-day empiricist. (shrink)