Traditionally, nature has often been thought to be structured by essential forms providing the generic features of natural things and thus the foundations for scientific explanations. In contrast, human history and the social domain have been thought to be the realm of ever-changing appearances, where contingency prevails. The paper argues that the existence of essential forms is compatible with the contingent, mind-dependent and historical character of the social world, and that essential forms can also be found in the social domain. (...) Two categories of entities are discussed that suggest themselves to be identified as social forms, namely social kinds and social identities. To this end, it is shown that standard arguments for the existence of essential forms also apply to the social domain, and objections to the existence of social forms are rebutted. Particular attention is paid to the explanatory appeal of social forms. The paper concludes by suggesting that, far from being oppressive, essential social forms are presupposed by liberating social practices. (shrink)