The internal sense (Antarindriya): An analysis of Manas in the epistemology of internal perception (Mānasa-pratyakṣa)

Abstract

In classical Indian epistemology, the perception of external objects through sensory organs is meticulously theorized. However, the mechanism by which internal states such as pleasure (sukha), pain (duḥkha), and desire (icchā) are known remains a more nuanced subject. This paper conducts a focused investigation into the concept of mānasa-pratyakṣa (mental perception) within the Nyāya-Vaiśeṣika and Mīmāṃsā schools of thought. Drawing on primary Sanskrit sources like Gautama's Nyāya Sūtras and Śabara's commentary on the Mīmāṃsā Sūtras, the study argues that these traditions posit a sophisticated model of introspection that is fundamentally perceptual, not inferential. It demonstrates that manas (mind) is not merely a coordinator of external senses but is theorized as a true antarindriya (internal sense organ), the sole instrument capable of directly apprehending the non-physical qualities (guṇa) of the Self (Ātman). By analyzing the logic that necessitates this model, the paper clarifies a crucial aspect of Indian philosophy of mind, distinguishing it from models where introspection is a higher-order thought or reflection. This analysis reaffirms the role of manas as the indispensable gateway to the inner world of subjective experience.