Worrying about a paradox was nonsensical. That much followed necessarily from basic tenets of logic, despite all the effort that was wasted on reasoning and theorizing how to avoid such presumable existential catastrophes. A paradox, put simply, was an event that did not make sense. A contradiction come to pass. Such an event could only occur in a stratum of existence that itself did not make sense. To fear a paradox was to recognize the threat it posed, but to do that was to concede one's own reality did not necessarily follow cause and effect. To entertain that notion was to invite in every impossible doubt imaginable.
Certainly, a universe could be conceived where everything was consistent, advancing down the course of cause and effect, with the sole exception of time travel. In such a hypothetical existence, a paradox could occur, introducing an inconsistency with disastrous consequences. Such a universe could even be consistent with observations of one's own. However, it was equally as conceivable that there was another universe where an arbitrary, innocuous event magically carried apocalyptic ramifications, without any cause. An anomalous inconsistency in a reality which otherwise made sense. It, too, could be indistinguishable from one's own, the specter of paradox haunting the unseen future.
These were all possible candidates for the reality one can observe, each one as likely as any other. Their potential ramifications thus hung over any and every action. Every decision carried the weight of an infinitude of chances, from sudden apocalypse to utopia and everything in between in equal measure. How, then, could any choice be weighed, any outcome predicted, or any understanding be maintained? Rationality required those nonsensical potentialities to be cast out. The assumption that some consistent set of rules governed existence was a necessary predicate of any form of rationality. How could one apply logic to something without first assuming that it obeyed logic? How could one rationally act without accepting it as given that causality was real, not an illusion born of constant coincidence?
Those fundamental axioms were necessary, and outright precluded the notion of a paradox. Reality would prove self-consistent, and entertaining any contrary thought defeated itself. Not that everyone accepted that argument, as solid as it was. There was a persistent human tendency to elevate circumstances of time travel beyond other potential exceptions to the rule. There was a reason, of course, but ultimately merely a specious one. Causality was a necessary assumption, but cause and effect being linearly attached to the direction of time was merely a theory, based on observation. That much could, theoretically, prove wrong or incomplete, without jeopardizing the validity of reason itself.
Not that there was anyone present to object, or be convinced.