Across that abyss, there is only one bridge. Few races, unaided, have ever found it. Some have turned back… — Arthur C. Clarke

Across that abyss, there is only one bridge. Few races, unaided, have ever found it. Some have turned back while there was still time, avoiding both the danger and the achievement. Their worlds have become Elysian islands of effortless content, playing no further part in the story of the universe. That would never have been your fate—or your fortune. Your race was too vital for that. It would have plunged into ruin and taken others with it, for you would never have found the bridge.

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