Difference between revisions of "Occam's razor"

Revision as of 05:40, June 4, 2007

Ockham's Razor is one of the most widely used ontological principles in all fields of applied logic, most notably philosophy, theology, and systemology. It is attributed to William of Ockham, an English Franciscan Friar who lived in the late thirteenth and early fourteenth centuries. Briefly, it can be stated as follows:

'From any set of equally probable explanations, we should assume the one which makes the least fundamental assumptions is correct, until we have reason to believe otherwise'

This is different from the shortest explanation, the shortest logical argument, and the simplest explanation, and the razor is often incorrectly quoted and/or applied. Some people have argued that these criteria qualify as better principles than the razor.

Ockham's razor can be illustrated be the following common example. A tree is found uprooted in the middle of a field with no apparent cause. Two people offer competing hypotheses for how this occured. Person A says that there must have been a storm last night, which combined with heavy rainfall the previous day, resulted in the uprooting of the tree. Person B says that last night aliens visited the planet Earth, and uprooted the tree as a message to mankind. There is no way of determining which of these hypotheses is correct after the fact, but as A's hypothesis makes far fewer fundamental assumptions (basically that the planet Earth has weather) than B's hypothesis (basically that aliens exist, have a way of finding humans in the cosmos, have a way of traversing space to reach our planet, could topple such a tree without being noticed, and so forth), we should assume A is correct and that a storm felled the tree unless B can provide some other evidence to support their claim.

John Wisdom and Anthony Flew indirectly use the razor in The Parable of the Gardener.

Among its practical applications, Occam's Razor has been used by both sides in the debate between theism and atheism. Let us take for an example the origin of intelligent life on Earth. One possibility for intelligent life is evolution via natural selection. A second possibility is God. Advocates of the Anthropic Principle might contend that evolution is the means through which God works. However, Occam's Razor allows us to eliminate God from the hypothesis, since the idea is an unnecessary assumption. The 'simpler' explanation (that which makes fewer fundamental assumptions) is that God had nothing to do with the development of Intelligent Life and that it came about as a result of natural processes. Therefore, the earlier explanation is the most reasonable to believe. Of course proponents of theistic evolution might include a different scenario. Let us assume a man needs to go from Boise Idaho to Billings Montana. He sets off and through an incredible stroke of luck just happens to walk from Boise to Billings - or he got a map and a compass and then walked. Well, using a map and compass are extra steps, therefore, based upon the same logic used above, it is evident the man merely walked it and just happened to get from Boise to Billings through chance.