For each new class which puts itself in the pace of one ruling before it, is compelled… to represent its interests as the common interests of all the members of society, expressed in ideal form… The class making a revolution appears from the very start, if only because it is opposed to a class, not as a class but as the representative of the whole of society: it appears as the whole mass of society confronting the one ruling class. It can do this because, to start with, its interest really is more connected with the common interests of all other non-ruling classes, because under the pressure of hitherto existing conditions its interest has not yet been able to develop as the particular interests of a particular class. Its victory, therefore, benefits also many individuals of the other classes which are not wining a dominate position, but only insofar as it now puts these individuals in a position to raise themselves into the ruling class.
Marx K and Engels F. (1974) The German Ideology, London: Lawrence & Wishart Limited – pp. 65-66