  Disturbances in environments cause maladaptations; progressive adaptation only has meaning in reference to that which is stable. Science must be economical so that a stable basis for our orientation can be built up, and this leads to a crucial point: as science encompasses more and more of the world, and as these theories work themselves into our unconscious memory, more and more of the world becomes part of our pre-existing cognitive structure. That is, the role of science is to improve our orientation to the world.