Sutra is a Sanskrit word that means "Supreme Truth
(“thread”) A sutra is a brief sentence or aphorism that may be readily
memorized in a metaphorical sense.
Many early philosophical and grammatical books were
compilations of such sutras, which are so small that a commentary to clarify
their content is almost required.
In many situations, the commentary would have been an oral
interchange between teacher and pupil, resulting in the live transmission that
is still prevalent in tantra, a hidden, ritual-based religious practice.
Memorizing such sutras was a technique to master a complete
text, and the sutras may also be used as a memory aid for the commentary, allowing
a person to keep track of the argument's "thread." The term sutra may
also refer to the string or cords that were strung through the centers of palm
leaf manu scripts to keep the pages of the text in their right sequence.
You may also want to read more about Hinduism here.
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