CHAPTER VIII.

THE EUROPEAN AGE OF REASON.

REJECTION OF AUTHORITY AND TRADITION, AND ADOPTION OF SCIENTIFIO TRUTH.-DISCOVERY OF THE TRUE POSITION OF THE EARTH IN THE

UNIVERSE.

Ecelesiastical Attempt to enforce the GEOCENTRIC DOCTRINE that the Earth is the Centre of the Universe, and the most important Body in it.

The HELIOCENTRIC DOCTRINE that the Sun is the Centre of the Solar System, and the Earth a small Planet, comes gradually into Prominence.

Struggle between the Ecclesiastical and Astronomical Parties.-Activity of the Inquisition.-Burning of BRUNO.-Imprisonment of GALILEO. INVENTION OF THE TELESCOPE.-Complete Overthrow of the Ecclesiastical Idea.-Rise of Physical Astronomy.-NEWTON.-Rapid and resistless Development of all Branches of Natural Philosophy.

Final Establishment of the Doctrine that the Universe is under the Dominion of mathematical, and, therefore, necessary Laws.

Progress of Man from the Anthropocentric Ideas to the Discovery of his true Position and Insignificance in the Universe.

THE Age of Reason in Europe was ushered in by an astronomical controversy.

Is the earth the greatest and most noble body in the An astronom- universe, around which, as an immovable centre, ical problem. the sun, and the various planets, and stars revolve, ministering by their light and other qualities to the wants and pleasures of man, or is it an insignificant orba mere point-submissively revolving, among a crowd of compeers and superiors, around a central sun? The former of these views was authoritatively asserted by the Church; the latter, timidly suggested by a few thoughtful and religious men at first, in the end gathered strength and carried the day.

Behind this physical question-a mere scientific problem -lay something of the utmost importance-the Its important position of man in the universe. The conflict conseqences. broke out upon an ostensible issue, but every one saw what was the real point in the dispute.

of Reason.

In the history of the Age of Reason in Europe, which is to fill the remaining pages of this book, I am Treatment constrained to commence with this astronomical of the Age controversy, and have therefore been led by that circumstance to complete the survey of the entire period from the same, that is, the scientific point of view. Many different modes of treating it spontaneously present themselves; but so vast are the subjects to be brought under consideration, so numerous their connexions, and so limited the space at my disposal, that I must give the preference to one which, with sufficient copiousness, offers also precision. Whoever will examine the progress of European intellectual advancement thus far manifested will find that it has concerned itself with three great questions: 1. The ascertainment of the position of the earth in the universe; 2. The history of the earth in time; 3. The position of man among living beings. Under this last is ranged all that he has done in scientific discovery, and all those inventions which are the characteristics of the present industrial age.

What am I? Where am I? we may imagine to have been the first exclamations of the first man awakening to conscious existence. Here, in our Age of Reason, we have been dealing with the same thoughts. They are the same which, as we have seen, occupied Greek intellectual life.

66

When Halley's comet appeared in 1456, it was described by those who saw it as an object of "unheard- Roman astroof magnitude; its tail, which shook down nomical ideas. diseases, pestilence, and war upon earth, reached over a third part of the heavens. It was considered as connected with the progress of Mohammed II., who had just then taken Constantinople. It struck terror into all people. From his seat, invisible to it, in Italy, the sovereign pontiff, Calixtus III., issued his ecclesiastical fulminations; but the comet in the heavens, like the sultan on

the earth, pursued its course undeterred. In vain were all the bells in Europe ordered to be rung to scare it away; in vain was it anathematized; in vain were prayers put up in all directions to stop it. True to its time, it punctually returns from the abysses of space, uninfluenced by anything save agencies of a material kind. A signal lesson for the meditations of every religious man. Among the clergy there were, however, some who had more correct cosmic ideas than those of Calixtus. A century before Copernicus, Cardinal de Cusa had partially adopted the heliocentric theory, as taught in the old times by Philolaus, Pythagoras, and Archimedes. He ascribed to the earth a globular form, rotation on its axis, and a movement in space; he believed that it moves round the sun, and both together round the pole of the universe.

More correct ideas among Some of the clergy.

By geocentric theory is meant that doctrine which asserts the earth to be the immovable centre of The geocentric and heliocen- the universe; by heliocentric theory that which tric theories. demonstrates the sun to be the centre of our planetary system, implying, as a necessary influence, that the earth is a very small and subordinate body revolving round the sun.

I have already, in sufficient detail, described how the Roman Church had been constrained by her position to

The geocentric doctrine adopted by the Church.

uphold the geocentric doctrine. She had come to regard it as absolutely essential to her system, the intellectual basis of which she held would be sapped if this doctrine should be undermined. Hence it was that such an alarm was shown at the assertion of the globular form of the earth, and hence the surpassing importance of the successful voyage of Magellan's ship. That indisputable demonstration of the globular figure was ever a solid support to the scientific party in the portentous approaching conflict.

Preparations

Préparations had been silently making for a scientific revolution in various directions. The five for the helio- memoirs of Cardinal Alliacus "On the Concordance of Astronomy with Theology," show the turn that thought was taking. His "Imago Mundi" was published in 1460, and is said to have been a

centric doc

trine.

favourite work with Columbus. In the very Cathedral of Florence, Toscanelli had constructed his celebrated gnomon, 1468, a sun-ray, auspicious omen! being admitted through a plate of brass in the lantern of the cupola. John Muller, better known as Regiomontanus, had published an abridgment of Ptolemy's "Almagest," 1520. Euclid had been printed with diagrams on copper as long before as 1482, and again in Venice twenty-three years subsequently. The Optics of Vitello had been published 1533. Fernel, physician to Henry II. of France, had even ventured so far, supported by Magellan's voyage, as to measure, 1527, the size of the earth, his method being to observe the height of the pole at Paris, then to proceed northward until its elevation was increased exactly one degree, and to ascertain the distance between the stations by the number of revolutions of his carriage wheel. He concluded that it is 24,480 Italian miles round the globe. The last attempt of the kind had been that of the Khalif Almaimon seven hundred years previously on the shore of the Red Sea, and with nearly the same result. The mathematical sciences were undergoing rapid advancement. Rhæticus had published his trigonometrical tables; Cardan, Tartaglia, Scipio Ferreo, and Stefel were greatly improving algebra.

The first formal assertion of the heliocentric theory was made in a timid manner, strikingly illustrative of the expected opposition. It was by Copernicus, a Copernicus, Prussian, speaking of the revolutions of the the works of heavenly bodies; the year was about 1536. In his preface, addressed to Pope Paul III., whether written by himself, or, as some have affirmed, for him by Andreas Osiander, he complains of the imperfections of the existing system, states that he has sought among ancient writers for a better way, and so had learned the heliocentric doctrine. "Then I too began to meditate on the motion of the earth, and, though it appeared an absurd opinion, yet, since I knew that in previous times others had been allowed the privilege of feigning what circles they chose in order to explain the phenomena, I conceived that I might take the liberty of trying whether, on the supposition of the earth's motion, it was possible to find better

explanations than the ancient ones of the revolutions of the celestial orbs."

"Having, then, assumed the motions of the earth, which are hereafter explained, by laborious and long observation I at length found that, if the motions of the other planets be compared with the revolution of the earth, not only their phenomena follow from the suppositions, but also that the several orbs and the whole system are so connected in order and magnitude that no one point can be transposed without disturbing the rest, and introducing confusion into the whole universe."

66

The apologetic air with which he thus introduces his Introduction doctrine is again remarked in his statement that of his system. he had kept his book for thirty-six years, and only now published it at the entreaty of Cardinal Schomberg. The cardinal had begged of him a manuscript copy. Though I know that the thoughts of a philosopher do not depend on the judgment of the many, his study being to seek out truth in all things as far as is permitted by God to human reason, yet, when I considered how absurd my doctrine would appear, I long hesitated whether I should publish my book, or whether it were not better to follow the example of the Pythagoreans and others, who delivered their doctrine only by tradition and to friends." He concludes: "If there be vain babblers who, He fears being accused of knowing nothing of mathematics, yet assume heresy. the right of judging on account of some place of Scripture perversely wrested to their purpose, and who blame and attack my undertaking, I heed them not, and look upon their judgments as rash and contemptible."

Copernicus clearly recognized not only the relative position of the earth, but also her relative magnitude. He says the magnitude of the world is so great that the distance of the earth from the sun has no apparent magnitude when compared with the sphere of the fixed stars. To the earth Copernicus attributed a triple motion-a daily rotation on her axis, an annual motion round the sun, a motion of declination of the axis. The latter seemed to be necessary to account for the constant direction of the pole; but as this was soon found to be a misconception, the

Early correction of the

Copernican theory.