 Popper’s angle of approach here is to situate the development of knowledge in the context of animal and human evolution. It is characteristic of evolutionary processes, he points out, that they come to take place in an environment which is itself in part fashioned by the species in question. Examples of this abound, such as the reefs built by corals, the hives built by bees, the dams built by beavers and the atmospheric effects yielded by plants. This, Popper contends, is also true of human beings: we too have created new kinds of products, “intellectual products”, which shape our environment. These are our myths, our ideas, our art works and our scientific theories about the world in which we live. When placed in an evolutionary context, he suggests, such products must be viewed instrumentally, as exosomatic artefacts. Chief amongst them is knowledge