relations of
production, or, which is only a juridical expression for the same thing,
with the relations of property within which they had hitherto moved.
From forms for the development of these forces of production, they are
transformed into their fetters. We then enter upon an epoch of social
revolution."[3]

This completely materialist conception of history is one of the greatest
discoveries of our century, so rich in scientific discoveries. Thanks to
it alone sociology has at last, and for ever, escaped from the vicious
circle in which it had, until then, turned; thanks to it alone this
science now possesses a foundation as solid as natural science. The
revolution made by Marx in social science may be compared with that made
by Kopernicus in astronomy. In fact, before Kopernicus, it was believed
that the earth remained stationary, while the sun turned round it. The
Polish genius demonstrated that what occurred was the exact contrary.
And so, up to the time of Marx, the point of view taken by social
science, was that of "human nature;" and it was from this point of view
that men attempted to explain the historical movement of humanity. To
this the point of view of the German genius is diametrically opposed.
While man, in order to maintain his existence, acts upon nature outside
himself, he alters his own nature. The action of man upon the nature
outside himself, pre-supposes certain instruments, certain means of
production; according to the character of their means of production men
enter into certain relations within the process of production (since
this process is a social one), and according to their relations in this
social process of production, their habits, their sentiments, their
desires, their methods of thought and of action, in a word, their
nature, vary. Thus it is not human nature which explains the historical
movement; it is the historical movement which fashions diversely human
nature.

But if this is so, what is the value of all the more or less laborious,
more or less ingenious enquiries into "perfect legislation" and the best
of possible social organisations? None; literally none! They can but
bear witness to the lack of scientific education in those who pursue
them. Their day is gone for ever. With this old point of view of human
nature must disappear the Utopias of every shade and colour. The great
revolutionary party of our day, the International Social-Democracy, is
based not upon some "new c