It now remains for me to reply briefly to his observations—­and they are few and far between—­on the relations which exist between contemporary socialism and the general trend and tendency of thought in the exact sciences.

Disregarding the arguments which I had developed on this subject by pointing out that there is an essential connection between economic and social transmutation (Marx) and the theories of biological transmutation (Darwin) and of universal transmutation (Spencer), M. Garofalo has thought it prudent to take up for consideration only “the struggle for existence” and the relations between “evolution and revolution.”

As to the first, five pages (96-100) are enough to enable him to declare, without supporting his declaration by any positive argument which is not merely a different verbal expression of the same idea, that the Darwinian law of the struggle for existence has not undergone and can not undergo any transformation except that which will change the violent struggle into competition (the struggle of skill and intelligence) and that this law is irreconcilable with socialism; for it necessarily requires the sacrifice of the conquered, while socialism “would guarantee to all men their material existence, so they would have no cause for anxiety.”

But my friend, the Baron Garofalo, quietly and completely ignores the fundamental argument that the socialists oppose to the individualist interpretation that has hitherto been given of the struggle for life and which still affects the minds of some socialists so far as to make them think that the law of the struggle for life is not true and that Darwinism is irreconcilable with socialism.

The socialists, in fact, think that the laws of life are the following, and that they are concurrent and inseparable:  the struggle for existence and solidarity in the struggle against natural forces.  If the first law is in spirit individualist, the second is essentially socialistic.

Now, not to repeat what I have written elsewhere, it is sufficient here for me to establish this positive fact that all human evolution is effected through the constantly increasing predominance of the law of solidarity over the law of the struggle for existence.

The forms of the struggle are transformed and grow milder, as I showed as long ago as 1883, and M. Garofalo accepts this way of looking at the matter when he recognizes that the muscular struggle is ever tending to become an intellectual struggle.  But he has in view only the formal evolution; he wholly disregards the progressive decrease in the importance of the struggling function under the action of the other parallel law of solidarity in the struggle.

Here comes in that constant principle in sociology, that the social forms and forces co-exist always, but that their relative importance changes from epoch to epoch and from place to place.