Allan Kardec

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1. The first idea that man forms of the Earth, of the movements of the stars, and of the constitution of the universe, must be, in the commencement of his observations, entirely based upon the testimony of the senses. In his ignorance of the most elementary laws of physics, and of the forces of nature, having only his limited sight as a means of observation, he was able to judge only by appearances.

As he beheld the sun appear in the morning outside of the horizon and disappear in the evening on the other side, he naturally concluded that it revolved around the Earth, whilst the latter remained stationary. If it had been suggested to him that the contrary was the truth, he would have replied that that was impossible; for would he not have declared that we see the sun change its position, and we do not feel the Earth move?

2. The few facts known then by voyagers, whose journeys rarely exceeded the limits of their tribe or of the valley in which they dwelt, would not permit of their establishing a spherical Earth. In what way could they arrive at the conclusion that the Earth is a ball? Men would not have been able to support this assertion; and, in supposing it inhabited on its entire surface, how would they have supposed it possible to live in opposite hemispheres, the head down and feet up? The fact would have appeared less possible when the rotational movement of the globe should have been explained. When one sees in our day, when the law of gravitation is known, people relatively enlightened, unable to give an account of this phenomenon, is it astonishing that men in the early ages had not even suspected it?

The Earth to them was a flat surface, circular as a millstone, extending out of sight in the far horizon, hence arose the saying yet in use: “Going to the end of the world.” Its limits, its thickness, its interior, its inferior surface that which was beneath them, was unknown to them.*

* Hindu mythology taught that the sun was “divested in the evening of its light, and traversed the sky during the night with an obscured face. Greek mythology represented the car of Apollo as drawn by four horses. Anaximander of Miletus maintained in concord with Plutarch, that the sun was a chariot tilled with a very brilliant fire, which escaped through a circular opening. Epicurus gave as his opinion that the sun was lighted in the morning, and extinguished at night in the waters of the ocean. Others thought that it was made of pumice-stone heated to a state of incandescence. Anaxagoras regarded it as a heated iron of the magnitude of the Peloponnesus. Strange to relate, the ancients were so invincibly determined to consider the apparent size of this body as real, that they persecuted this rash philosopher for having attributed such magnitude to the torch of day, that Pericles was obliged to exercise all the power of his authority to save him from condemnation to death, and commute the latter to a sentence of exile.” (Flammarion: “Studies and Lectures upon Astronomy,” p. 6.) If they held such ideas in the fifth century, before the Christian Era, in the most flourishing times of Greece, we cannot be astonished at those entertained by men in earlier times on the system of the universe.

3. The heavens, appearing to be concave in form constituted, according to common belief, a real vault, the lower borders of which rested on the Earth and marked the end of it, — a vast dome, the space of which was filled with air. With no idea of the infinity of space, incapable even of conceiving it, men imagined this vault formed of solid matter; whence the name of “firmament” which has survived such a belief, and which signifies firm, enduring (from the Latin firma mentum, derived from firmus, “firm”, and from the Greek herma, hermatos, a prop, or supporter, or fulcrum).

4. The stars, of the nature of which they had no suspicions, were to them simply luminous points, small and large, attached to the vault like suspended lamps, disposed on one surface only, consequently all at the same distance from the Earth, in the manner in which they are represented in the interior of certain cupolas, which are painted blue in imitation of the azure hue of the sky.

Although today ideas are changed, the usage of the ancient expressions is retained. We say yet, for example, “the starry vault;” “under heaven’s arch.”

5. The formation of clouds by the evaporation of the waters of the Earth was then equally unknown. They did not suspect that the rain which falls from the sky arose in vapor from the Earth; for they did not see the water arise. Whence the belief in large and small bodies of water from celestial and terrestrial sources, from reservoirs situated in lofty regions, — a supposition which accorded perfectly with the idea of a solid vault capable of maintaining them. The larger bodies of water, escaping through fissures in the sky, fell in rain; and the rain fell gently or came in torrents, according to the size of these openings.

6. The complete ignorance of the whole universe, and of the laws which rule it, of the nature, constitution, and destination of the stars, which seemed, besides, so small compared with the Earth, would necessarily make the latter to be considered as the principal object in creation, and the stars as accessories created solely to give light to its inhabitants. These prejudices are cherished by some to this day, despite the discoveries of science, which have altered the aspects of the world for mankind. Many people believe still that the stars are ornaments of the sky, placed there to please the eye of man.

7. They delayed not to perceive the apparent movement of the stars in a body from east to west, rising in the evening, and going down in the morning, preserving their respective positions. This observation had for a long time no other result than that of confirming the idea of a solid vault carrying the stars along in its rotary movement.

These first simple ideas have made, during long secular periods, the foundation of religious beliefs, and have served as a base for all ancient cosmogonies.

8. Later they discovered, by the direction of the movement of the stars, and their periodical return in the same order, that the celestial vault could not be simply a hemisphere resting upon the Earth, but a hollow sphere, in the center of which was the Earth, flat at the utmost convex, and inhabited only upon its upper surface. This was a progressive idea.

But upon what rested the Earth? It would be useless to relate all the ridiculous suppositions born of the imagination. That of the Indians, who declared it was supported by four white elephants, the latter standing on the wings of a vulture; is sufficient for an example. Wise people avowed that they knew nothing about it.

9. However, a general opinion, extending into pagan theogonies, appointed the lower place, otherwise called the depths of the Earth, or under it — they knew not much about it — for the sojourn of the reprobates, and called it hell; and in celestial heights, beyond the region of the stars, they fixed the home of the blessed. The word “hell” is now used, although it should have lost its etymological signification, since geology has dislodged the place of eternal sorrow from the center of the Earth, and astronomy demonstrated that there are neither upper nor lower directions in space.

10. Under the clear sky of Chaldea, India, and Egypt, cradle of the most antique civilization, one could observe the movement of the stars with as much precision as the absence of special instruments permitted. They saw at first that certain stars had a movement of their own independent of the rest, which caused them to no longer believe that they were attached to the vault. They called them wandering stars or planets, in order to distinguish them from fixed stars. They calculated their movements and periodical returns.

In the diurnal movement of the starry spheres they observed the immovableness of the polar star, around which others described, in twenty-four hours, oblique or parallel circles, smaller or greater, according to their distance from the central star. This was the first step towards the knowledge of the obliquity of the world’s axis. Moreover, long voyages enabled them to observe the change of aspect in the sky according to latitudes and seasons. The elevation of the polar star above the horizon varying with the latitude, suggested the idea of the roundness of the Earth. Thus little by little they arrived at more accurate ideas of the system of the world.

Towards the year 600 B.C., Thales of Miletus, Asia Minor, became convinced of the sphericity of the Earth, the obliquity of the ecliptic, and the cause of the eclipses.

A century later Pythagoras of Samos discovered the diurnal movement of the Earth upon its axis, its annual movement around the sun, and connected the planets and comets to the solar system.

One hundred and sixty years B.C., Hipparchus of Alexandria, Egypt, invented the astrolabe, calculated and predicted the eclipses, observed the spots on the sun, ascertained the tropical year and the duration of the revolutions of the moon.

However precious these discoveries were for the progress of science, they were nearly two thousand years in becoming popularized. These new ideas, having then as a means of diffusion only a few rare manuscripts, which remained in the possession of some philosophers who taught them to privileged disciples, the masses of the people, whom they dreamed not of enlightening, profited nothing by them, but continued to cherish old beliefs.

11. Towards the year 140 of the Christian Era, Ptolemy, one of the most illustrious men of the Alexandrian school, combining his own ideas with common beliefs, and a few of the more recent astronomical discoveries, composed a system, which one can call a compound of beliefs, which took his name, and during a period of nearly fifteen centuries was solely adopted in the civilized world.

According to the theory of Ptolemy, the Earth is a sphere in the center of the universe, and is composed of four elements, — earth, water, air, and fire. This is the first region, called “elementary.” The second, called “the ethereal,” comprised eleven heavens, or concentric spheres, turning around the Earth; viz., that of the moon, those of Mercury, Venus, of the sun, Mars, Jupiter, Saturn, of the fixed stars, of the first crystalline heaven (a solid transparent sphere), of the second crystalline sphere, and at last of the outer circle, of primitive mobility, which, by its motion, was supposed to carry around all those within it, causing them to make a revolution every twenty-four hours. Beyond these eleven spheres was the Empyrean, or highest sphere, “abode of the blessed,” thus named from the Greek pyr or pur, which signifies “fire,” because they believed this region to be resplendent with light like fire.

The belief in many superposed heavens or spheres has prevailed for a long time; but they varied in regards to number. The seventh was generally regarded as the highest, whence the expression, “to be carried to the seventh heaven.” St. Paul said that he had been elevated to the third heaven.

Independent of the general motion, the stars had, according to Ptolemy, some particular movements of their own, greater or less according to their distance from the center. The fixed stars made a revolution in 25,816 years. This last computation denotes knowledge of the precession of the equinoxes, which is actually accomplished in about 25,868 years.

12. At the commencement of the sixteenth century, Copernicus, a celebrated astronomer, born at Thorn, Prussia, in 1472, and who died in 1543, reproduced the ideas of Pythagoras. He published a system which, confirmed each day by new observations, was favorably received, and was not long in proving that of Ptolemy to be unreliable. According to this system, the sun is the center; the planets describe circular orbs around this body of light; the moon is a satellite of the Earth.

A century later, in 1609, Galileo, born at Florence, invented the telescope. In 1610 he discovered the four satellites of Jupiter, and calculated their revolutions. He recognized that the planets have no light like the stars, but that they receive light from the sun; that they are spheres similar to the Earth. He observed their phases, and determined the duration of their rotation upon their axes. He thus gave, by material proofs, a definite sanction to the system of Copernicus.

From this period the belief in superposed heavens was extinguished. The stars are innumerable suns, probable centers of as many planetary systems. The planets were recognized as worlds similar to the Earth, and like it, without doubt, inhabited. The sun was believed to be a star, and the center around which the planets, which are subject to it, revolve.

The stars are no more confined to a zone of the celestial sphere, but are irregularly disseminated in limitless space. Those which appear to touch each other are immeasurable distances apart. The smallest, in appearance, are the farthest from us; the largest, those which are nearest, are hundreds of thousands millions of miles distant from us.

The groups which have gained the name of constellations are only apparent assemblages caused by distance, perspective effects, such as appear to the view of him who is placed at a fixed point from lights dispersed over a vast plain, or the trees of a forest. But these assemblages do not in reality exist. If one could be transported into the region of one of these constellations by measure, as one would approach, the form would disappear, and new groups would design themselves to the sight.

Since these groups do not really exist, the signification that a common superstitious belief attributes to them is illusory, as they have only as groups an imaginary existence.

In order to distinguish the constellations, names have been given to them, such as these of: Lion, Bull, Twins, Virgin, Balance, Goat, Crab, Orion, Hercules, Great Bear or Chariot of David, Little Bear, Lyre, etc.; and they have been represented by figures corresponding to these names, but which in every case have but fanciful connection with the apparent forms of the starry groups. We should then seek in vain for these figures in the sky.

The belief in the influence of the constellations, particularly those which constitute the twelve signs of the Zodiac, comes from the idea attached to the names they bear. If that which is called Lion had been named Donkey or Lamb, people would have attributed to it a totally different influence.

13. Galileo and Copernicus destroyed the old cosmogonies. Astronomical knowledge advanced: it could not retrograde. History records the difficulties these men of genius had to encounter through prejudice, especially through the sectarian spirit of the times, which was interested in the maintenance of errors upon which the priesthood had founded beliefs considered unchangeable. The invention of an optical instrument has been the means of destroying the trelliswork of the beliefs of many thousands of years. Nothing could prevail against a truth which could be demonstrated to man’s vision. Thanks to the art of printing, the public gained a knowledge of the new ideas; and while some recognize their truth, and took part in the struggle for truth, it soon became necessary to combat, not simply a few individuals, but general opinion, which would take its part in the contest for truth.

How grand the universe is compared with the narrow proportions our forefathers assigned to it! How sublime God’s work when we see its accomplishment according to the laws of nature! But only with the aid of time, and the affords and devotion of men of genius, were the sealed eyes opened, and the bandage of ignorance removed.

14. Henceforth the way will be open for numerous and illustrious wise men to enter upon the completion of the outlined work. Kepler, in Germany, discovered the celebrated laws which bear his name, and by the aid of which he discovered that planets describe not circular orbs but ellipses, of which the sun occupies one of the focuses. Newton, in England, discovered the law of universal gravitation. Laplace, in France, created celestial mechanics. In short, astronomy is no more a system founded upon conjecture and probability, but a science established upon the most rigorous bases of arithmetic and geometry. Thus one of the cornerstones of Genesis is laid, approximately 3,300 years after Moses.

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