Thief of Time - Rules

There was something called The Rules, Susan knew. They weren’t written down, in the same way that mountains weren’t written down. They were far more fundamental to the operation of the universe than mere mechanical things like gravity. The Auditors might hate the untidiness caused by the emergence of life, but The Rules did not allow them to do anything about it. The ascent of mankind must have been a boon to them. At last there was a species that could be persuaded to shoot itself in the foot.

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The Thief of Time - p90