which serve as the expression of its conditions and the comprehension of its own organization enable it at the same time to gain an insight into the organization and the conditions of production which had prevailed under all the past forms of society, on the ruins and constituent elements of which it has arisen, and of which it still drags along some unsurmounted remnants, while what had formerly been mere intimation has now developed to complete significance. The anatomy of the human being is the key to the anatomy of the ape. But the intimations of a higher animal in lower ones can be understood only if the animal of the higher order is already known. The bourgeois economy furnishes a key to ancient economy, etc. This is, however, by no means true of the method of those economists who blot out all historical differences and see the bourgeois form in all forms of society. One can understand the nature of tribute, tithes, etc., after one has learned the nature of rent. But they must not be considered identical.
Since, furthermore, bourgeois society is but a form resulting from the development of antagonistic elements, some relations belonging to earlier forms of society are frequently to be found in it but in a crippled state or as a travesty of their former self, as e.