Another difficulty which DeVries claims to have solved by his theory, is the supposed contradiction between the physicist and the biologist as to the time allowed by the former and the time required by the latter, for the evolution of animals.
Lord Kelvin asserted the age of the earth to be between twenty and forty million years. George Darwin estimates the separation of the moon from the earth as having taken place some fifty-six million years ago. Gekie estimated the existence of the solid crust of the earth as at most hundred million years. Joly, by calculating the amount of dissolved salts, and Dubois by the amount of lime, estimated the age of the rivers, Joly giving as probable fifty-five and Dubois thirty-six millions of years.
“All in all,” concludes DeVries, “it seems evident that the duration of life does not comply with the demands of the conception of very slow and continuous evolution.” Mutation, with its sudden leaps, has no such difficulty, and,--“The demands of the biologists and the results of the physicists are harmonized on the ground of the theory of mutation.”
In order properly to estimate the sociological significance of DeVries’ theory it will be necessary to go back more than a century, and observe the sociological import of the leading biological ideas of that period.
And here let us remark, that nobody knows better than we do the danger of transplanting, without criticism, biological theories into the field of sociology. Nevertheless, our opponents have never lost an opportunity to twist and distort science, if perchance by any possibility it could be made to contradict anything that had so much as the semblance of Socialism. We, however, have always insisted on the weakness of reasoning by mere analogy and have kept to those general laws which have been worked out separately in sociology.
The principle now about to be applied belongs to this latter class. It is the most luminous principle ever employed in the interpretation of the phenomena of society. This principle is that the intellectual life of a people is determined by its mode of wealth production and the social classes arising therefrom.
Jean Lamarck, the first great modern apostle of evolution, died in poverty because he advocated a theory that appeared to contradict the interests of the ruling class of his time. He had against him all that survived of feudal interests, which was intensely theological, and although his theory really favored the bourgeoisie, that class was not yet aware of it.