Ryan Muldoon

As scientists begin to study increasingly complex questions, many have turned to computer simulation to assist in their inquiry. This methodology has been challenged by both analytic modelers and experimentalists. A primary objection of analytic modelers is that simulations are simply too complicated to perform model verification. From the experimentalist perspective it is that there is no means to demonstrate the reality of simulation. The aim of this paper is to consider objections from both of these perspectives, and to argue that a proper understanding and application of robustness analysis is able to resolve them. ‡The author would like to thank Cristina Bicchieri, Michelle Foa, Paul Humphreys and Michael Weisberg for their helpful comments and suggestions. †To contact the author, please write to: Department of Philosophy, University of Pennsylvania, 433 Logan Hall, 249 S. 36th Street, Philadelphia, PA, 19104-6304; e-mail: [email protected].

In epistemology and the philosophy of science, there has been an increasing interest in the social aspects of belief acquisition. In particular, there has been a focus on the division of cognitive labor in science. This essay explores several different models of the division of cognitive labor, with particular focus on Kitcher, Strevens, Weisberg and Muldoon, and Zollman. The essay then shows how many of the benefits of the division of cognitive labor flow from leveraging agent diversity. The essay concludes by examining the benefits and burdens of diversity, particularly in the evaluative diversity that can be found in interdisicplinary science.

Scientific research is almost always conducted by communities of scientists of varying size and complexity. Such communities are effective, in part, because they divide their cognitive labor: not every scientist works on the same project. Philip Kitcher and Michael Strevens have pioneered efforts to understand this division of cognitive labor by proposing models of how scientists make decisions about which project to work on. For such models to be useful, they must be simple enough for us to understand their dynamics, but faithful enough to reality that we can use them to analyze real scientific communities. To satisfy the first requirement, we must employ idealizations to simplify the model. The second requirement demands that these idealizations not be so extreme that we lose the ability to describe real-world phenomena. This paper investigates the status of the assumptions that Kitcher and Strevens make in their models, by first inquiring whether they are reasonable representations of reality, and then by checking the models' robustness against weakenings of these assumptions. To do this, we first argue against the reality of the assumptions, and then develop a series of agent-based simulations to systematically test their effects on model outcomes. We find that the models are not robust against weakenings of these idealizations. In fact we find that under certain conditions, this can lead to the model predicting outcomes that are qualitatively opposite of the original model outcomes

This paper explores the space of possibilities for public justification in morally diverse communities. Moral diversity is far more consequential than is typically appreciated, and as a result, we need to think more carefully about how our standard tools function in such environments. I argue that because of this diversity, public justification can be divorced from any claim of determinateness. Instead, we should focus our attention on procedures—in particular, what Rawls called cases of pure procedural justice. I use a modified form of the procedure “I cut, you choose” to demonstrate how perspectival diversity can make what looks like a simple procedure quite complex in practice. I use this to reframe disputes between classical liberal and contemporary liberal approaches to questions of public morality, arguing that classically liberal procedures, such as a reliance on the harm principle, can generate rather illiberal-looking outcomes when used in a morally diverse community. A seemingly less-principled approach, which simply balances burdens, appears to generate outcomes that look closer to what we would expect from classical liberalism. However, since both approaches are based on pure procedures that we can justify without reference to outcomes, it remains indeterminate which we ought to choose.