106 JOURNAL OF SCIENCE. 
could never have been arrived at by a study of the complicated: 
organic molecule, neither could a knowledge of the principle of 
selection have been arrived at by a study of the complicated 
phenomena of sociology ; it was in biology alone that it could be 
detected, and it is to biology that we must turn for the proofs of 
its power. 
But there is another theory of history which I must not pass 
over, as it also is supposed to be founded on biological data. 
The curious analogy that undoubtedly exists between a state, or 
social organism, as it has been called, and an animal, or indivi- 
dual organism, has been commented on by many writers ever 
since the days of Plato and Aristotle. The tissues of which an 
animal is built up are composed of cells, or units of organisation; 
and these units of organisation are supposed to represent the 
individuals which compose the state or nation. As the cells 
constantly die and are replaced, so do the individual human 
beings, while the nation lives on. A nation exhibits the pheno- 
mena of growth, structure, and function, like those of an individual 
body,* and in development both pass through changes which 
are not permanent. The governing or controlling power is 
supposed to represent the nervous system; the trading or 
distributing body to represent the vascular system, and so on. 
On the strength of this analogy many inferences have been 
drawn. The heart has been likened to the metropolis, and an 
overgrown metropolis is therefore said to be a disease. Because 
all parts of the body obey the mandates of the brain, imperialism, 
or at any rate centralization, has been advocated as the best 
form of government. As individuals have a limited period of 
existence, so also must it be with nations. This is the leading 
idea of Vico’s “Scienza Nuova,” and we see it again in Lord 
Macaulay’s celebrated New Zealander sitting on the ruins of 
London bridge. 
But the analogy is incomplete and misleading. Human 
beings are not so different from one another as are the various 
cells of which one of the higher animals is built up, and nothing 
can make them so different. In these animals each cell can only 
play its own part ; but we know from experience that in a state 
a mancan pass from a working member to be a controlling 
member, and often acts as efficiently as if he had always been 
a controlling member. Sancho Panza truly says, “ As to 
governing well, the main point, in my mind, is to make a good 
beginning ; and that being done, who knows but that by the 
time I have been fifteen days a governor, my fingers may get so 
nimble in the office that they will tickle it off better than the 
drudgery I was bred to in the field.” Indeed, it would not 
be difficult to find in this analogy as many discrepancies as 
likenesses. What, for instance, in the organisation of an animal 
answers to the professions of theology, medicine, or law? What 
to prisons and reformatories ? How is it that in the individual, 
* Herbert Spencer. 
