Sean Donahue

Collective procedural memory is a group’s memory of how to do things, as opposed to a group’s memory of facts. It enables groups to mount effective responses to periodic events (e.g., natural hazards) and to sustain collective projects (e.g., combatting climate change). This article presents an account of collective procedural memory called the Ability Conception. The Ability Conception has various advantages over other accounts of collective procedural memory, such as those appealing to collective know-how and collective identity. It also demonstrates new applications for collective procedural memory. I develop three in this article: to social epistemology, to the ethics of memorialization, and to a pattern of group vulnerability to recurring hazardous events that I call the saeculum effect.

According to the Public Justification Principle, legitimate laws must be justifiable to all reasonable citizens. Proponents of this principle assume that its satisfaction requires speakers to offer justifications that are representable as arguments that feature premises which reasonable listeners would accept. I develop the concept of dark knowledge to show that this assumption is false. Laws are often justified on the basis of premises that many reasonable listeners know, even though they would reject these premises on the basis of the further considerations that speakers implicitly rely on for their support. Accommodating the fact of dark knowledge requires us to consider the civic virtue of speakers to be more important for public justification than the acceptability of their arguments to reasonable citizens. I sketch an alternative conception of public justification that incorporates these results and argue that it provides a rationale for ignoring the otherwise sound contributions of some participants in political deliberation.

Public reason liberals claim that legitimate rules must be justifiable to diverse perspectives. This Public Justification Principle threatens that failing to justify rules to reprehensible agents makes those rules illegitimate. Although public reason liberals have replies to this objection, they cannot avoid the challenge of powerful deceivers. Powerful deceivers trick people who are purportedly owed public justification into considering otherwise good rules to be unjustified. Avoiding this challenge requires discounting some failures of justification, according to what caused people’s beliefs. I offer a conception of public justification that accommodates these externalist considerations while positioning Public Reason Liberalism to provide insight into real cases of deception.

Public reason liberals claim that legitimate rules must be justifiable to diverse perspectives. This Public Justification Principle threatens that failing to justify rules to reprehensible agents makes them illegitimate. Although public reason liberals have replies to this objection, they cannot avoid the challenge of powerful deceivers. Powerful deceivers trick people who are purportedly owed public justification into considering otherwise good rules unjustified. Avoiding this challenge requires discounting some failures of justification according to what caused people’s beliefs. I offer a conception of public justification that accommodates these externalist considerations while positioning Public Reason Liberalism to provide insight into real cases of deception.

The Public Justification Principle requires that coercive institutions be justified to all who live under them. I argue that this principle often cannot be satisfied without persons depending on the pure informative testimony of others, even under realistically idealized situations. Two main results follow. First, the sense of justification relevant to this principle has a strongly externalist component. Second, normative expectations of trust are essential to public justification. On the view I propose, whether the Public Justification Principle is satisfied depends on the features of the network of testifiers in which persons are embedded. I consider several such networks to show which features are plausibly relevant. The importance of testimony for public justification ultimately suggests that we should moderate our expectations about the kind of conciliation we can achieve with the social order in which we live.

Two epistemic principles are Knowledge Exclusion and Belief Exclusion. Knowledge Exclusion says that it is necessarily the case that if an agent knows that p, then she does not believe that ∼p, and Belief Exclusion says that it is necessarily the case that if an agent believes that q, then she does not believe that ∼q. Many epistemologists find it reasonable to reject the latter principle and accept the former. I argue that this is in fact not reasonable by proposing a case in which an agent can use that she has contradictory beliefs towards a proposition as decisive evidence for that proposition. A natural response is that this case conflicts with common assumptions about the relation between knowledge, contradictory beliefs and rationality. I reply by drawing ideas from Lasonen-Aarnio’s remarks on unreasonable knowledge to explain why these common assumptions do not threaten my argument.