The doctrine of *neti neti* (“not this, not that”) discloses an Upanishadic mode of inquiry that advances by systematic negation rather than by affirmative description. Ultimate reality—Brahman, identical with the true Self, Ātman—is regarded as beyond all finite predicates, so every determinate concept, image, or object of experience is set aside as inadequate. Whatever can be grasped by the senses, thought by the mind, or fixed in language is subjected to this process of exclusion. In this way, the Upanishadic sages indicate that any attempt to define the Absolute in positive terms inevitably limits what is, by its very nature, limitless.

This negative or apophatic method also reveals a deep awareness of the limitations of conceptual thought. Since Brahman transcends all categories of human understanding, no verbal formula or doctrinal statement can finally capture it. *Neti neti* thus functions as a rigorous discipline of discernment, training the seeker to distinguish the eternal Self from all that is changeable—body, emotions, thoughts, and even subtle states of consciousness. By progressively withdrawing identification from these layers, inquiry is directed toward what remains as unchanging witness-consciousness.

At the same time, this doctrine underscores that authentic knowledge of the Self is not merely intellectual but fundamentally experiential. The repeated negation of “this” and “that” does not leave a void of meaning; rather, it clears away false identifications so that direct realization of Brahman as pure awareness may dawn. In this sense, the Upanishadic path is both analytical and contemplative: it uses reason to exhaust the reach of reason, and then points beyond it to an immediate recognition that cannot be fully expressed in words.