In this paper we shed new light on the Argument from Disagreement by putting it to test in a computer simulation. According to this argument widespread and persistent disagreement on ethical issues indicates that our moral opinions are not influenced by any moral facts, either because no such facts exist or because they are epistemically inaccessible or inefficacious for some other reason. Our simulation shows that if our moral opinions were influenced at least a little bit by moral facts, we would quickly have reached consensus, even if our moral opinions were affected by factors such as false authorities, external political shifts, and random processes. Therefore, since no such consensus has been reached, the simulation gives us increased reason to take seriously the Argument from Disagreement. Our conclusion is however not conclusive; the simulation also indicates what assumptions one has to make in order to reject the Argument from Disagreement. The simulation algorithm we use builds on the work of Hegselmann and Krause (J Artif Soc Social Simul 5(3); 2002, J Artif Soc Social Simul 9(3), 2006).
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Early versions of this paper were presented to audiences at conferences and seminars at the University of Colorado at Boulder, Stockholm University, Uppsala University, Lund University, Luleå University of Technology, Delft University of Technology, and the Buenos Aires Metaethics Workshop. We would like to thank the participants for very helpful comments. We also wish to thank two anonymous reviewers for equally helpful comments.
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Gustafsson, J.E., Peterson, M. A computer simulation of the argument from disagreement. Synthese 184, 387–405 (2012). https://doi.org/10.1007/s11229-010-9822-3
- Moral realism
- Opinion dynamics