Anumāna

Anumāna (अनुमान) is the pramāṇa of inference — knowledge that arises through a logical process connecting what is perceived to what is not directly observed. It is the second of the pramāṇas in the Nyāya system and the primary instrument of rational inquiry. The Nyāya tradition formulates inference through a five-membered syllogism (pañcāvayava-vākya): proposition (pratijñā), reason (hetu), example (udāharaṇa), application (upanaya), and conclusion (nigamana).

The logical structure rests on the relationship of vyāpti (pervasion or invariable concomitance) between the reason (hetu) and the property to be proved (sādhya). For instance: “The hill has fire (proposition), because it has smoke (reason); where there is smoke there is fire, as in the kitchen (example); the hill is such that it has smoke (application); therefore the hill has fire (conclusion).” Navya-Nyāya, as systematized by Gaṅgeśa, refined this into a highly formalized logical apparatus.

In Buddhist logic, Dignāga and Dharmakīrti developed a three-membered syllogism (proposition, reason, example) that drops the Nyāya application and conclusion members, focusing instead on the universal relationship. Dignāga distinguished svārthānumāna (inference for oneself, reasoning from observed to unobserved) and parārthānumāna (inference for others, communicated through a syllogistic structure), a division retained by Dharmakīrti. The Buddhist tradition treats inference as always conceptual (savikalpaka), grasping the general (sāmānyalakṣaṇa) rather than the particular.

Verification notes

• The Nyāya five-membered syllogism is attested in Vātsyāyana’s Bhāṣya and the Nyāya Sūtra critical edition.
• Gaṅgeśa’s Tattvacintāmaṇi is the foundational text of Navya-Nyāya logic.
• Dharmakīrti’s Pramāṇavārttika (svārthānumāna and parārthānumāna chapters) provides the definitive Buddhist treatment of anumāna.
• Audited against Wikipedia (September 2026).