Sunday, 5 September 2010

Robert Nozick on Reason and Evolution

                        “Reason and Evolution” is the title of the first chapter of Hayek’s “Law, Legislation and Liberty” (1973). It could also be the name of a whole new discipline. Here I found a citation from “The Nature of Rationality” (1993), by Robert Nozick, that would fit under that label: “Principles help you to discover the truth by transmitting evidential support or probability from some cases to others. Principles also help you to overcome temptation by transmitting utility from some actions to others. Principles are transmission devices for probability and for utility. / Principles have various functions and effects: intellectual, intrapersonal, personal, and interpersonal. This is not to say that they have these effects in every possible situation. A temperature regulatory mechanism will work only within a certain range of temperature; beyond that range it will not be able to bring temperature back, and, depending upon its material, it may even melt or freeze. Why didn’t evolution give us better regulatory mechanism for body temperature? Given the small probability that such extreme cases will arise, that would be too costly in terms of energy and attendant sacrifice in other functions. A mechanism can perform its function pretty well, well enough, even if it will not work for some of the situations that might arise. Similarly for principles” (Princeton University Press, pages 35-36).