The central task of this chapter is to show why systematic correlationism - whether as correlationist realism, ESA and OSA - runs into unavoidable problems in philosophy of science. To this end, I will reconstruct and modify Meillassoux’s arguments, which he introduces in the context of the problem of ancestrality. To this end, I will integrate into my analysis the extensive criticism that has been levelled at the ancestral question in the course of the debate. In addition, my consideration of ancestrality can help to defuse the sometimes scathing criticism of Meillassoux’s concept in essential respects by modifying and clarifying it at vital points. A key to the successful reformulation of the problem of ancestrality lies in the differentiation of two levels of the problem that I will discuss in what follows: It arises in the correlationist treatment of scientific discourse on the first, scientific-discourse level and in the question of the genesis and enabling conditions of each correlation on the second, ontological level. In the course of my discussion of both, I will again take up the example of correlationism from the previous chapter and show why the inherent problems of these positions become apparent when they are confronted with the ancestral question.