Lacking the great generalizations of biology, it was, as we have said, “impossible to trace out the real relations of special organizations to organizations of another order.” Therefore he proposes “to show what are the analogies which modern science discloses.” Spencer then discovers four points in which an individual organism and a society agree, and four in which they differ. The points of agreement are: (1.) “That commencing as small aggregations, they insensibly augment in mass; some of them eventually reaching ten thousand times what they originally were.” (2.) “That while at first so simple in structure as to be considered structureless, they assume in the course of their growth a continually increasing complexity of structure.” (3.) “That though in their early, undeveloped states, there exists in them scarcely any mutual dependence of parts, their parts gradually acquire a mutual dependence; which becomes at last so great, that the activity and life of each part is made possible only by the activity and life of the rest.” (4.) “That the life of a society is independent of, and far more prolonged than the lives of any of its component units; who are severally born, grow, work, reproduce, and die, while the body politic composed of them survives generation after generation, increasing in mass, in completeness of structure, and in functional activity.” The four points of difference are: (1.) “That societies have no specific external forms.” (2.) “That though the living tissue whereof an individual organism consists, forms a continuous mass, the living elements of a society do not form a continuous mass; but are more or less widely dispersed over some portion of the earth’s surface.” (3.) “That while the ultimate living elements of an individual organism are mostly fixed in their relative positions, those of the social organism are capable of moving from place to place.” (4.) “The last and perhaps the most important distinction is, that while in the body of an animal only a special tissue is endowed with feeling, in a society all the members are endowed with feeling.” It is worthy of note that, while Spencer finds the parallelisms to increase in significance the more they are examined, the differences tend to break down when they are worked out in detail. The advantage which Spencer had over Plato and Hobbes is very clearly seen in the first and fourth parallelisms, neither of which could have been made until twenty-one years before, when in 1839, Theodore Schwann developed his great theory that the body is an organized society of interconnected cells. “The importance of this theory,” says Professor Thatcher, “can hardly be estimated. It gave an entirely new view to animal and vegetable life.” At any rate, it served Spencer greatly in this essay.