From Arthur C. Clarke’s Interplanetary Flight: An Introduction to Astronautics (London: Temple Press Limited, 1960):

There is no way back into the past; the choice, as Wells once said, is the universe–or nothing. Though men and civilizations may yearn for rest, for the dream of the lotus-eaters, that is a desire that merges imperceptibly into death. The challenge of the great spaces between the worlds is a stupendous one; but if we fail to meet it, the story of our race will be drawing to its close.

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