Similarly, it happens to be an a priori truth that all consciousnesses find themselves inside of a continuum that is made up of bits of realityfluid in identity-points related by directed cause-and-effect laws (eg quantum amplitudes, in dath ilan). And all these continuums of causal relation are causally well-founded; they contain no infinite sequences of causes of causes going forever backwards in time.
Different continua have different Big Bangs—different degenerate-zero-points in their relations between the stuff of realness. But they all have some equivalent of a Big Bang.
Some continuums last forever, they causally increase in time forever—though they necessarily become less and less real as they go, for no stretch of realness can sum to being infinitely real. But a cause-of-effect sequence never goes back forever.
As a special case of this rule, time never goes in a loop. Because then again one could talk of a cause, and a cause's cause, and a cause's cause's cause, and so on forever, even if you were covering the same territory and repeating yourself. If you say that A > B > C > A... then that's not a well-ordered set even if it's a finite one.