Philosophical Dictionary, by Voltaire


Astrology might rest on a better foundation than magic. For if no one has seen farfadets, or lemures, or dives, or peris, or demons, or cacodemons, the predictions of astrologers have often been found true. Let two astrologers be consulted on the life of an infant, and on the weather; if one of them say that the child shall live to the age of man, the other that he shall not; if one foretell rain and the other fair weather, it is quite clear that there will be a prophet.

The great misfortune of astrologers is that the heavens have changed since the rules of the art were laid down. The sun, which at the equinox was in the Ram in the time of the Argonauts, is now in the Bull; and astrologers, most unfortunately for their art, now attribute to one house of the sun that which visibly belongs to another. Still, this is not a demonstrative argument against astrology. The masters of the art are mistaken; but it is not proved that the art cannot exist.

There would be no absurdity in saying, “Such a child was born during the moon’s increase, in a stormy season, at the rising of a certain star; its constitution was bad, and its life short and miserable, which is the ordinary lot of weak temperaments; another, on the contrary, was born when the moon was at the full, and the sun in all his power, in calm weather, at the rising of another particular star; his constitution was good, and his life long and happy.” If such observations had been frequently repeated, and found just, experience might, at the end of a few thousand centuries, have formed an art which it would have been difficult to call in question; it would have been thought, not without some appearance of truth, that men are like trees and vegetables, which must be planted only in certain seasons. It would have been of no service against the astrologers to say, “My son was born in fine weather, yet he died in his cradle.” The astrologer would have answered, “It often happens that trees planted in the proper season perish prematurely; I will answer for the stars, but not for the particular conformation which you communicated to your child; astrology operates only when there is no cause opposed to the good which they have power to work.”

Nor would astrology have suffered any more discredit from it being said: “Of two children who were born in the same minute, one became a king, the other nothing more than churchwarden of his parish;” for a defence would easily have been made by showing that the peasant made his fortune in becoming churchwarden, just as much as the prince did in becoming king.

And if it were alleged that a bandit, hung up by order of Sixtus the Fifth, was born at the same time as Sixtus, who, from being a swineherd, became pope, the astrologers would say that there was a mistake of a few seconds, and that, according to the rules, the same star could not bestow the tiara and the gallows. It was, then, only because long-accumulated experience gave the lie to the predictions that men at length perceived that the art was illusory; but their credulity was of long duration.

One of the most famous mathematicians of Europe, named Stöffler, who flourished in the fifteenth and sixteenth centuries, foretold a universal deluge for the year 1524. This deluge was to happen in the month of February, and nothing can be more plausible, for Saturn, Jupiter, and Mars were then in conjunction in the sign of the Fishes. Every nation in Europe, Asia, and Africa that heard of the prediction was in consternation. The whole world expected the deluge, in spite of the rainbow. Several contemporary authors relate that the inhabitants of the maritime provinces of Germany hastened to sell their lands, at any price, to such as had more money and less credulity than themselves. Each one provided himself with a boat to serve as an ark. A doctor of Toulouse, in particular, named Auriol, had an ark built for himself, his family, and friends; and the same precautions were taken in a great part of Italy. At last the month of February arrived, and not a drop of rain fell, never was a month more dry, never were the astrologers more embarrassed. However, we neither discouraged nor neglected them; almost all our princes continued to consult them.

I have not the honor to be a prince; nevertheless, the celebrated Count de Boulainvilliers and an Italian, named Colonna, who had great reputation at Paris, both foretold to me that I should assuredly die at the age of thirty-two. I have already been so malicious as to deceive them thirty years in their calculation — for which I most humbly ask their pardon.

Last updated Tuesday, March 4, 2014 at 18:25