2.0 - Extraterrestrial Life: The History of an Idea

Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization

First Edition

Robert A. Freitas Jr., Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization, First Edition, Xenology Research Institute, Sacramento, CA, 1979; http://www.xenology.info/Xeno.htm

"Empty space is like a kingdom, and earth and sky are no more than a single individual person in that kingdom.
"Upon one tree are many fruits, and in one kingdom there are many people.
"How unreasonable it would be to suppose that, besides the earth and the sky which we can see, there are no other skies and no other earths."
-- Teng Mu, a Chinese scholar of the Sung Dynasty (960 -- 1280 A.D.)¹⁹⁰⁴

"We may pronounce each orb sustains a race
Of living things, adapted to the place.
Were all the stars, whose beauteous realms of light,
At distance only hung to shine by night,
And with their twinkling beams to please our sight?
How many roll in ether, which the eye
Could ne‘er, till aided by the glass, descry;
And which no commerce with the Earth maintain!
Are all those glorious empires made in vain?
-- Sir Richard Blackmore, in Creation (1712)⁷⁴⁷

"That which makes me of this Opinion, that those worlds are not without such a Creature endowed with Reason, is that otherwise our Earth would have too much the advantage of them, in being the only part of the Universe that could boast of such a Creature...
-- Christian Huygens, in The Celestial Worlds Discover‘d; Or, Conjectures Concerning the Inhabitants, Plants and Productions of the Worlds in the Planets (1698)⁶⁰²

"Extraterrestrial life is truly an idea whose time has come."
-- Dr. Carl Sagan, in The Cosmic Connection (1973)¹⁵

The idea that intelligent but nonhuman living beings might exist somewhere has tantalized the minds of men since the dawn of recorded history. Virtually every civilization or major culture on Earth has entertained some such speculation, whether in its mythology, its religious or scientific writings, or in its philosophy of nature.

The sophisticated concept of aliens indigenous to planets circling faraway stars did not blossom into existence overnight, however. The theme of extraterrestrial life has slowly evolved over the course of many millennia of pensive human contemplation. Before it was accepted that Earth was a mere planet and that many others could exist, intelligent nonhuman beings were commonly viewed in a mythological context. But as man learned to appreciate the vast scale of the universe, the idea of life in the physical cosmos matured and gained wider currency.*

* There are many good historical introductions to both the scientific^{747,1754,1769,1872} and the fictional^{1896,1897,1872} literature.