The ‘polar’ model of class relationships is only a simplified way of describing elements of those phenomena which actually occur as complex class structures. In naming that relationship antagonistic, we may disregard its psychological aspects, since we are concerned neither with the psychological antagonism of individuals nor with the structure of mental attitudes occurring in a social group as a result of the positions held by members of that group, but with the mutual relationship of those positions, which is the principle of the structure of the model. A given antagonistic mode of production consists in the association of definite social productive forces with definite social class relations. Those class relations consist, in turn, in the association of those social positions which make it possible to exercise a special form of power over the working conditions of other people, and to appropriate the product of their work, with those social positions which deprive their holders of the possibility of controlling their own working conditions and force them to part, in a special form, with the product of their work on behalf of those who exercise the power mentioned above. The antagonistic nature, or the opposition, of the two kinds of social positions thus associated has here the same meaning as the opposition of the two different and inseparable poles of a magnet which by its very nature is a ‘magnetic dipole’.