The article presents the aporias that are found in classical Brahmin philosophical systems when their ontological assumptions are confronted with the fundamental metaphysical thesis formulated in the Upanishads. This thesis determines the way in which the absolute being is described: sat ekam advitiyam (existing one only, without a second). The wording considerably resembles Parmenidesʼ description of being. Later European history of philosophy shows various problems that appear in subsequent systems when we attempt to construct a coherent ontological system which includes the Parmenidean concept of being. The account presented is not strictly comparative, and it mostly analyses selected Indian systems. It shows analogous processes of the origination of key metaphysical ideas peculiar to given traditions. It also indicates significantly similar difficulties which are connected with assuming the Parmenidean understanding of absolute being in Europe, as well as the Upanishadic thesis in India.

The article presents the aporias that are found in classical Brahmin philosophical systems when their ontological assumptions are confronted with the fundamental metaphysical thesis formulated in the Upanishads. This thesis determines the way in which the absolute being is described: sat ekam advitiyam (existing one only, without a second). The wording considerably resembles Parmenidesʼ description of being. Later European history of philosophy shows various problems that appear in subsequent systems when we attempt to construct a coherent ontological system which includes the Parmenidean concept of being. The account presented is not strictly comparative, and it mostly analyses selected Indian systems. It shows analogous processes of the origination of key metaphysical ideas peculiar to given traditions. It also indicates significantly similar difficulties which are connected with assuming the Parmenidean understanding of absolute being in Europe, as well as the Upanishadic thesis in India.