In the imagination of those who are sensitive to the realities of our era, the earth has become a spaceship, and this, perhaps, is the most important single fact of our day. For millennia, the earth in men’s minds was flat and illimitable. Today, as a result of exploration, speed, and the explosion of scientific knowledge, earth has become a tiny sphere, closed, limited, crowded, and hurtling through space to unknown destinations. This change in man’s image of his home affects his behaviour in many ways, and is likely to affect it much more in the future.

Kenneth Ewart Boulding (1910-1993) American economist, educator, poet, philosopher

“Earth as a Spaceship,” Lecture, Washington State University (10 May 1965)
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