Why do many Evolutionary biologists not find it necessary to address the question of whether Darwinian theory is true?
The monopoly of science in the realm of knowledge explains why evolutionary biologists do not find it meaningful to address the question whether the Darwinian theory is true. They will gladly concede that the theory is incomplete, and that further research into the mechanisms of evolution is needed. At any given point in time, however, the reigning theory of naturalistic evolution represents the state of scientific knowledge about how we came into existence. Scientific knowledge is by definition the closest approximation of absolute truth available to us.
