Rta is the earliest term the Vedic corpus uses for order, and it is notably not described as having been decreed. The seasons follow rta. Rivers run by rta. The sun rises in accordance with it. Deities are described as guardians of rta, protecting and following it, never as its authors. This is a fine distinction and it decides the whole character of the concept: rta is not legislation but pattern, and it is prior to anyone who might enforce it.
The difference matters because a decreed law can in principle be repealed by whoever decreed it, which makes the order contingent on a will. Rta cannot be repealed, and no story exists of its founding. It is closer to what a physicist means by a regularity than to what a jurist means by a statute, and it is closer still to something for which English has no single word: a pattern that is normative, so that departing from it is not merely unusual but wrong.
That normative edge is what distinguishes it from mere description. Deviation from rta is called anrta, and anrta is used for falsehood as well as for disorder, which tells you the two were not felt to be different problems. Truthfulness, seasonal regularity and moral conduct are all instances of one thing holding. The later term dharma inherits much of this and adds social and ethical texture that rta did not originally carry, which is the shift traced under Sanatana Dharma.
An order that nobody made and nobody can amend is a demanding thing to build a civilisation on. To see what it became, explore more of The Living Sanatan Timeline.
Part 25 of 100 — Series I: From the Beginning
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