Two Meditations on the Thoughts of Many Minds, Book Review
26 Pages Posted: 31 Mar 2013
Date Written: 2010
Sometimes it is a good thing to follow the herd. If you think one thing but everyone else thinks another, sometimes you will do better by accepting that they are right — even if you do not understand how they reached their conclusion — than by continuing to rely on your own judgment. If the world tells you that a tasty-looking plant is poisonous, it is probably best not to eat it, however enticing it looks. On the other hand, sometimes you will do better by sticking to your own opinion. Lots of people may think a thing, but lots of people may be wrong. History is littered with popular beliefs that are now widely regarded as mistaken. Some of these errors are straightforward factual mistakes: the sun does not revolve around the earth and inhaling the night air is not harmful. Others are moral mistakes: people’s worth does not depend on their race or sexuality, and parents ought not to have the final say about whom their children marry. The trick is, of course, to be able to distinguish between those situations in which you should accept the verdict of others and those in which you should reject it. It is a hard trick to pull off.
Cass Sunstein’s 'A Constitution of Many Minds' and Adrian Vermeule’s 'Law and the Limits of Reason' provide complementary reflections upon the issues raised by this question. This paper examines three groups of arguments that engage with the issues they raise. First, there is a group of claims surrounding the Condorcet Jury Theorem. Condorcet demonstrated that, under certain conditions, where each person in a group has a better-than-50% chance of giving the right answer to a question, the more people who are added to that group, the higher the likelihood that the verdict of the group as a whole will be correct. Secondly, there is a collection of claims surrounding the pooling of information within groups, where each member of the group adds something to the pool, and the verdict of the group is consequently more likely to be correct than the decision of any one member of the group. Information may be pooled through a mechanism that allows people to combine disparate facts into a larger narrative. This can occur, as Friedrich Hayek argued, in a marketplace, where the cost of goods is the product of a wide range of dispersed information about the expense of materials and the tastes of consumers. Or it can occur through the Internet, where wikis and other facilities allow people to combine disparate information into a unified text. Information pooling can also occur through old- fashioned deliberation, where each member of a group brings new facts to the discussion or subjects the existing facts to fresh critique, and the verdict of the group as a whole is richer and more accurate than that of any single member. Finally, there is a further collection of arguments, also associated with the work of Hayek, that asserts that a form of evolution can sometimes produce efficient rules, rules that embody the collected but unarticulated wisdom of a community. Through a process of trial and error, successful rules have prospered, whilst foolish rules have been discarded or have withered away. These different collections of arguments share a common quality. They all demonstrate that, in some situations, the group can be wiser than any one of its members.
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