What is the difference between śruti and smṛti?

śruti is “heard” revelation (the Vedas); smṛti is “remembered” tradition (epics, Purāṇas, Dharmaśāstras).

Śruti, “that which is heard”, means the Vedas in their four layers, ending in the Upaniṣads. It is considered timeless revelation and is the highest authority in most Hindu schools.

Smṛti, “that which is remembered”, is everything composed by sages to explain and apply śruti: the Rāmāyaṇa and Mahābhārata, the Purāṇas, the Dharmaśāstras such as those of Manu and Yājñavalkya, and the Vedāṅgas. The Bhagavad Gītā is technically smṛti, as part of the Mahābhārata, but it is so revered that it is often treated like an Upaniṣad.

The classical rule is that if a smṛti clearly contradicts śruti, śruti prevails. In practice smṛti texts also reflect their own times, which is why traditions have always added the example of good people (sadācāra) and one's own conscience as guides to dharma. The Āgamas form a third stream, honoured by Śaiva, Vaiṣṇava and Śākta traditions.

Source: Manusmṛti ch. 2 (sources of dharma) · Gītā: smṛti treated like an Upaniṣad

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