Now the trouble with this clever analogy is that it breaks down completely when the comparison is carried beyond a certain point. Mr. Spencer himself notices some differences between the social body and the animal body, but declares that they are not of such fundamental character as to weaken the force of his analogy. One of these differences, however, can not be so lightly dismissed. If we compare a high type of animal organism with a high type of society, this striking unlikeness is discovered. In the former there is but one center of consciousness; in the latter there are many. "In the one," to quote Mr. Spencer's own words, "consciousness is concentrated in a small part of the aggregate. In the other it is diffused throughout the aggregate." The animal body has one brain, one center of thought, feeling, and life; the social body has numberless such centers. When we go back and compare the course of development in the two cases the difference noted comes into even greater prominence. The evolution of animal life is characterized by progressive centralization, the evolution of social life by progressive decentralization. In the lowest form of animal, the amoeba, there is no single center of life. The life is in all the parts; reproduction takes place simply by division. But with each successive advance above this lowest form there is developed more and more definitely a single center of consciousness. One part becomes distinctly differentiated as the sole seat of life. If that part is destroyed, the organism dies. Thus, "animal development has meant a concentration of the more important nervous elements and a merging of their separate activity in the common activity of a single consciousness."[39] [Footnote 39: Fairbanks. Introduction to Sociology, p. 44.] The law of progress is quite the reverse in social development. At a primitive stage there is a marked subjection of the individual elements of society to a central authority, whether that of the patriarch, the tribal head, or the tribal assembly. The individual has no economic, legal, or moral independence. But as society develops, the control which the whole exerts over the parts through authority and custom is gradually diminished. The individuality of the members of the social body becomes more and more marked. Individual freedom and responsibility are definitely recognized. Thus, the development of society has meant "the development of individuality in each of its members." It is a development of persons; the "social consciousness exists only in the discrete social elements which have become individual."[40] [Footnote 40: Fairbanks. Ibidem.] In a word, social evolution is accompanied by a growing individualization of the component elements of society, whereas animal development leads to ever-stronger concentration of the life of the organism in a single part.