Formal Approaches in Social Epistemology

20-21 September 2016, University of Bristol

Venue: Department of Philosophy, Cotham House, Room G16

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Catarina Dutilh Novaes (Groningen)
Remco Heesen (Cambridge)
Liam Kofi Bright (CMU)
Richard Pettigrew (Bristol)
Patricia Rich (Bristol)
Kevin Zollman (CMU)


Tuesday 20th September

10.30 – 10.45 Welcome / coffee & tea
10.45 – 12.00 Catarina Dutilh Novaes (Groningen)
12.00 – 1.00 Lunch
1.00 – 2.15 Remco Heesen (Cambridge)
2.15 – 2.30 Coffee
2.30 – 3.45 Patricia Rich (Bristol)
3.45 – 4.00 Coffee
4.00 – 5.15 Kevin Zollman (CMU)

Wednesday 21st September

10.00 – 10.15 Coffee & tea
10.15 – 11.30 Liam Kofi Bright (CMU)
11.30 – 11.45 Coffee
11.45 – 1.00 Richard Pettigrew (Bristol)



Catarina Dutilh Novaes: ‘Argumentation as transfer of epistemic assets: between credulity and conservativeness’

It is commonly held that two basic principles for the epistemically responsible agent are: to minimize false beliefs and to maximize true beliefs. Naturally, these two desiderata are often in tension with one another; strategies that serve one of them well often do poorly with respect to the other. Now, if knowledge is conceived as an essentially social phenomenon, the question then becomes how we can responsibly acquire knowledge from others. One way to maximize true beliefs is the credulous strategy: to take on board everything that reasonably reliable informants tell us, but at the risk of also taking on board a large number of false beliefs. Conversely, one way to minimize false beliefs is the conservative strategy: to reject most (or all) of what others tell us, but then again at the risk of rejecting a large number of true beliefs. And so, epistemically responsible agents should find a way to navigate between these two poles by neither trusting nor mistrusting everything that they are told. Arguably, exchanging reasons for one’s beliefs by means of argumentation is one way in which an agent can ‘screen’ bits and pieces of information passed on to her by others. In my talk, I explore the idea that argumentation serves the purpose of transfer of epistemic assets, such that the epistemic autonomy of the agent is preserved while also ensuring the possibility of truly learning from others (and thus avoiding solipsism).

Remco Heesen: Why the Priority Rule Does Not Exist

By now it is a truism that scientists are rewarded for their work with prestige, and this prestige is allocated according to the priority rule. The priority rule says that the first scientist to make a discovery takes all the credit for it. This helps philosophers predict what kinds of behavior scientists are incentivized to engage in. We argue that there is no such thing as the priority rule: what counts as a discovery and how much credit is awarded for a given discovery makes all the difference insofar as determining scientists’ actual incentives is concerned. We show this in two ways. First, we briefly review Strevens’ account of the optimality of the priority rule for the division of cognitive labor and show that his argument breaks down when slightly more complicated cases are considered. Second, we introduce a new game-theoretic model of scientists aiming to maximize credit in a context where only statistically significant results are publishable. We show that under some prima facie plausible interpretations of the priority rule this model generates very bad results – scientists claiming discoveries on the basis of essentially no evidence.


Liam Kofi Bright: ‘Peer Review of Multiple Projects’

Philosophers have known since Kuhn that the assessment of theories and the research projects they spur is a holistic affair. Background theories or paradigms are used to assess potential research projects, and the ability to generate fecund research projects is a criterion by which we evaluate theories and paradigms. I use a model of research proposal evaluation to argue that this holism does not go far enough. To avoid outcomes that are by our own lights information-dominated by available alternative sets of potential research proposals, we must evaluate sets of potential research proposals collectively, rather than each on its own theory-relative merits. Furthermore, I show that presently we decide what to fund via peer review processes that do not live up to this ideal of expanded-holism.  Due to our insufficient holism, we are thus presently not meeting the minimal epistemic standard of ensuring fields do not collectively pursue projects that promise to yield strictly less information about nature than available alternative bundles of research projects.

Richard Pettigrew: ‘On the accuracy of group credences’

We often ask for the opinion of a group of individuals. How strongly does the scientific community believe that the rate at which sea levels are rising increased over the last 200 years? How likely does the UK Treasury think it is that there will be a recession if the country leaves the European Union? What are these group credences that such questions request? And how do they relate to the individual credences assigned by the members of the particular group in question? According to the credal judgment aggregation principle, Linear Pooling, the credence function of a group should be a weighted average or linear pool of the credence functions of the individuals in the group. In this paper, I give an argument for Linear Pooling based on considerations of accuracy. And I respond to two standard objections to the aggregation principle.

Patricia Rich: ‘Strategic Choices in Information Cascades’

Information cascades are a widespread phenomenon in which the perceived agreement of early actors causes later actors to discard their private information in light of the overwhelming evidence provided by the early agreement; the group therefore loses potentially valuable information and may be misled by early evidence. This raises several questions, such as when we should expect cascades to occur, when they are rational or irrational for the participants and beneficial or harmful for the group, and (when harmful) how they may be prevented. It is especially important to understand cascades because they are often harmful and because of the belief that non-participants in real-life cascades are irrational. I suggest that existing analysis of cascades, especially within philosophy, has provided a problematically-incomplete picture of cascade behavior because it has neglected the possibility of strategic incentives. Including such incentives in cascade models supports the conclusion that individuals who fail to follow the crowd when it appears that it would be individually rational for them to do so — but when the group is likely to benefit from them doing otherwise — may actually be responding rationally to a strategic incentive to promote non-cascading behavior by other group members in the future. This finding has practical consequences, for example that stressing the repeated nature of a group’s interactions and making individual choices more transparent may help prevent harmful cascades.

Kevin Zollman: ‘The theory of games as a tool for the social epistemologist’

Traditionally, epistemologists have distinguished between epistemic and pragmatic goals.  This distinction has cast much of decision and game theory as irrelevant to epistemic enterprises.  It is said that these theories only apply in a pragmatic context because they are designed around the satisfaction of pragmatic desires.  In this talk, I will show that interesting and complex game theory problems will arise when we consider social epistemology.  Even if we restrict attention to purely epistemic motivations, members of epistemic groups will face a multitude of strategic choices.  After illustrating the conditions necessary for there to be non-trivial, purely epistemic games, I turn to a few case studies.  I illustrate several contexts where individuals who are concerned solely with the discovery of truth will nonetheless face difficult game theoretic problems.


Practical information

Walking directions from the Berkeley Square Hotel to Cotham House:

Directions from Bristol Airport:
The Bristol Flyer bus departs every 10 minutes from right outside the terminal, and makes stops at Temple Meads train station and at Bristol Bus Station.
Journey time is 30-40 minutes (depending on traffic); return tickets are £11 (valid for 1 month from purchase).

From Temple Meads to the Berkeley Square Hotel:
– by bus:

– walking:

From Bristol Bus Station to the Berkeley Square Hotel:
– by bus:

– walking:

There are also taxi ranks outside Temple Meads station and Bristol Bus Station, as well as near the department.
A cab ride from either of the above to the department will typically cost around £8-10 (modulo the usual factors).

To call a cab: 0117 925 26 26