ABSTRACT
We are apt to be so impressed with Newton's mathematical way that we forget that the eighteenth century belonged to Linnaeus and his disciples as much as to the astronomers and the natural philosophers. It is certainly possible to classify arbitrarily, as a child might order a stamp-collection by size or colour, or into those that have birds on them and those that do not. Classification by railway officials is clearly socially determined; and indeed Durkheim has suggested that in a deeper sense all classifications reflect the structure of the society in which they are made. Charles Darwin brought in successfully an evolutionary way of looking at species. The natural classification of organisms was explained by Darwin as a consequence of evolution by natural selection; what had been metaphors when words like 'family' were used now became theory.
