Cogito Ergo Sum and Tat Tvam Asi: Parallels between René Descartes and Adi Shankaracharya
Ganesh Bhat
Anubodhan September 28, 2026 DOI: 10.65885/anubodhan.v2n3.2026.117 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Theoretical or philosophical paper Qualitative Peer reviewed |
|---|---|
| Key points | Argues that Descartes' cogito establishes certainty only at the level of reflective thought, while Advaita Vedānta's neti, neti and mahāvākyas point beyond thought to non-dual awareness and direct realization (aparokṣānubhūti). The authors contend that Indian traditions integrate epistemology, metaphysics, and soteriology more comprehensively than Cartesian rationalism, and that concepts such as antaḥkaraṇa, prakṛti, the three guṇas, and māyā address mind-body interaction and causal regularity more elaborately than Descartes' pineal gland hypothesis and mechanism. |
Abstract
The paper undertakes a comparative philosophical study of the thought of René Descartes and Adi Shankaracharya, centring on the thematic convergence between the Cartesian dictum "Cogito, ergo sum" and the Vedāntic mahāvākya "Tat Tvam Asi", "Aham Brahmasmi", etc. Beginning with Descartes' method of methodological scepticism as articulated in Meditations on First Philosophy, the study highlights how radical doubt functions as an epistemological tool to arrive at indubitable certainty, culminating in the affirmation of the thinking self.This is placed in dialogue with the Upanishadic method of neti, neti, which similarly negates empirical reality but extends beyond epistemology into ontological realization.The paper further examines Descartes' conception of the self as res cogitans in relation to the Vedāntic understanding of Ātman as pure, self-revealing consciousness, arguing that while Descartes establishes certainty at the level of reflective thought, Advaita Vedānta transcends thought itself to assert non-dual awareness.The study also compares Descartes' rational proofs for the existence of God with Indian approaches to ultimate reality, noting parallels with the Upanishadic conception of Brahman as infinite and self-evident, while emphasizing the Vedāntic shift from logical demonstration to direct experiential realization (aparokṣānubhūti).In addressing mind-body interaction, Descartes' pineal gland hypothesis is contrasted with the Indian model of antaḥkaraṇa, which offers a more elaborate psychological framework integrating cognition, memory, and ego, and further situates the mind within the broader pursuit of liberation (mokṣa).Additionally, Descartes' mechanistic view of nature is examined alongside the Sāṅkhya theory of prakṛti and the doctrine of the three guṇas, demonstrating how Indian philosophy accommodates both causal regularity and qualitative diversity, enriched by the metaphysical concept of māyā.The paper argues that while Cartesian philosophy lays the groundwork for modern epistemology and scientific rationalism, Indian philosophical traditions develop these insights more comprehensively by integrating epistemology, metaphysics, and soteriology.Ultimately, the study concludes that Indian philosophy not only parallels