Sathya

Satya is the Sanskrit word for truth. It also refers to a virtue in Indian religions, referring to being truthful in one's thought, speech and action. In Yoga, satya is one of five yamas, the virtuous restraint from falsehood and distortion of reality in one's expressions and actions.

In the Vedas and later sutras, the meaning of the word satya () evolves into an ethical concept about truthfulness and is considered an important virtue. It means being true and consistent with reality in one's thought, speech and action.

A related concept, sattva, also derived from "sat", means true essence, nature, spiritual essence, character. Sattva is also a guṇa, a psychology concept particularly in the Samkhya school of philosophy, where it means goodness, purity, clean, positive, one that advances good true nature of self.

Satya is a central theme in the Vedas. It is equated with and considered necessary to the concept Ṛta (Sanskrit ऋतं ṛtaṃ) – that which is properly joined, order, rule, nature, balance, harmony. Ṛta results from Satya in the Vedas, states Holdrege, as it regulates and enables the operation of the universe and everything within it. Satya (truth) is considered essential, and without it, the universe and reality falls apart, cannot function.

In Rigveda, opposed to rita and satya are anrita and asatya (falsehood). Truth and truthfulness is considered as a form of reverence for the divine, while falsehood a form of sin. Satya includes action and speech that is factual, real, true and reverent to Ṛta in Book 1, 4, 6, 7, 9 and 10 of Rigveda. However, Satya isn't merely about one's past that is in context in the Vedas, it has one's current and one's future contexts as well. De Nicolás states, that in Rigveda, "Satya is the modality of acting in the world of Sat, as the truth to be built, formed or established".

Satya is a widely discussed concept in various Upanishads, including the Brihadaranyaka Upanishad where satya is called the means to Brahman, as well as Brahman (Being, true self). In hymn 1.4.14 of Brihadaranyaka Upanishad, Satya (truth) is equated to Dharma (morality, ethics, law of righteousness), as

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