History of the Conflict Between Religion and Science

by John William Draper

THEY ORIGINATE CHEMISTRY. In letters the Saracens embraced every topic that can amuse or edify the mind. In later times, it was their boast that they had produced more poets than all other nations combined. In science their great merit consists in this, that they cultivated it after the manner of the Alexandrian Greeks, not after the manner of the European Greeks. They perceived that it can never be advanced by mere speculation; its only sure progress is by the practical interrogation of Nature. The essential characteristics of their method are experiment and observation. Geometry and the mathematical sciences they looked upon as instruments of reasoning. In their numerous writings on mechanics, hydrostatics, optics, it is interesting to remark that the solution of a problem is always obtained by performing an experiment, or by an instrumental observation. It was this that made them the originators of chemistry, that led them to the invention of all kinds of apparatus for distillation, sublimation, fusion, filtration, etc.; that in astronomy caused them to appeal to divided instruments, as quadrants and astrolabes; in chemistry, to employ the balance, the theory of which they were perfectly familiar with; to construct tables of specific gravities and astronomical tables, as those of Bagdad, Spain, Samarcand; that produced their great improvements in geometry, trigonometry, the invention of algebra, and the adoption of the Indian numeration in arithmetic. Such were the results of their preference of the inductive method of Aristotle, their declining the reveries of Plato.

THEIR GREAT LIBRARIES. For the establishment and extension of the public libraries, books were sedulously collected. Thus the khalif Al-Mamun is reported to have brought into Bagdad hundreds of camel-loads of manuscripts. In a treaty he made with the Greek emperor, Michael III., he stipulated that one of the Constantinople libraries should be given up to him. Among the treasures he thus acquired was the treatise of Ptolemy on the mathematical construction of the heavens. He had it forthwith translated into Arabic, under the title of "Al-magest." The collections thus acquired sometimes became very large; thus the Fatimite Library at Cairo contained one hundred thousand volumes, elegantly transcribed and bound. Among these, there were six thousand five hundred manuscripts on astronomy and medicine alone. The rules of this library permitted the lending out of books to students resident at Cairo. It also contained two globes, one of massive silver and one of brass; the latter was said to have been constructed by Ptolemy, the former cost three thousand golden crowns. The great library of the Spanish khalifs eventually numbered six hundred thousand volumes; its catalogue alone occupied forty-four. Besides this, there were seventy public libraries in Andalusia. The collections in the possession of individuals were sometimes very extensive. A private doctor refused the invitation of a Sultan of Bokhara because the carriage of his books would have required four hundred camels.

There was in every great library a department for the copying or manufacture of translations. Such manufactures were also often an affair of private enterprise. Honian, a Nestorian physician, had an establishment of the kind at Bagdad (A.D. 850). He issued versions of Aristotle, Plato, Hippocrates, Galen, etc. As to original works, it was the custom of the authorities of colleges to require their professors to prepare treatises on prescribed topics. Every khalif had his own historian. Books of romances and tales, such as "The Thousand and One Arabian Nights' Entertainments," bear testimony to the creative fancy of the Saracens. Besides these, there were works on all kinds of subjects—history, jurisprudence, politics, philosophy, biographies not only of illustrious men, but also of celebrated horses and camels. These were issued without any censorship or restraint, though, in later times, works on theology required a license for publication. Books of reference abounded, geographical, statistical, medical, historical dictionaries, and even abridgments or condensations of them, as the "Encyclopedic Dictionary of all the Sciences," by Mohammed Abu Abdallah. Much pride was taken in the purity and whiteness of the paper, in the skillful intermixture of variously-colored inks, and in the illumination of titles by gilding and other adornments.

The Saracen Empire was dotted all over with colleges. They were established in Mongolia, Tartary, Persia, Mesopotamia, Syria, Egypt, North Africa, Morocco, Fez, Spain. At one extremity of this vast region, which far exceeded the Roman Empire in geographical extent, were the college and astronomical observatory of Samarcand, at the other the Giralda in Spain. Gibbon, referring to this patronage of learning, says: "The same royal prerogative was claimed by the independent emirs of the provinces, and their emulation diffused the taste and the rewards of science from Samarcand and Bokhara to Fez and Cordova. The vizier of a sultan consecrated a sum of two hundred thousand pieces of gold to the foundation of a college at Bagdad, which he endowed with an annual revenue of fifteen thousand dinars. The fruits of instruction were communicated, perhaps, at different times, to six thousand disciples of every degree, from the son of the noble to that of the mechanic; a sufficient allowance was provided for the indigent scholars, and the merit or industry of the professors was repaid with adequate stipends. In every city the productions of Arabic literature were copied and collected, by the curiosity of the studious and the vanity of the rich." The superintendence of these schools was committed with noble liberality sometimes to Nestorians, sometimes to Jews. It mattered not in what country a man was born, nor what were his religious opinions; his attainment in learning was the only thing to be considered. The great Khalif Al-Mamun had declared that "they are the elect of God, his best and most useful servants, whose lives are devoted to the improvement of their rational faculties; that the teachers of wisdom are the true luminaries and legislators of this world, which, without their aid, would again sink into ignorance and barbarism."

After the example of the medical college of Cairo, other medical colleges required their students to pass a rigid examination. The candidate then received authority to enter on the practice of his profession. The first medical college established in Europe was that founded by the Saracens at Salerno, in Italy. The first astronomical observatory was that erected by them at Seville, in Spain.

THE ARABIAN SCIENTIFIC MOVEMENT. It would far transcend the limits of this book to give an adequate statement of the results of this imposing scientific movement. The ancient sciences were greatly extended—new ones were brought into existence. The Indian method of arithmetic was introduced, a beautiful invention, which expresses all numbers by ten characters, giving them an absolute value, and a value by position, and furnishing simple rules for the easy performance of all kinds of calculations. Algebra, or universal arithmetic—the method of calculating indeterminate quantities, or investigating the relations that subsist among quantities of all kinds, whether arithmetical or geometrical—was developed from the germ that Diophantus had left. Mohammed Ben Musa furnished the solution of quadratic equations, Omar Ben Ibra him that of cubic equations. The Saracens also gave to trigonometry its modern form, substituting sines for chords, which had been previously used; they elevated it into a separate science. Musa, above mentioned, was the author of a "Treatise on Spherical Trigonometry." Al-Baghadadi left one on land-surveying, so excellent, that by some it has been declared to be a copy of Euclid's lost work on that subject.

ARABIAN ASTRONOMY. In astronomy, they not only made catalogues, but maps of the stars visible in their skies, giving to those of the larger magnitudes the Arabic names they still bear on our celestial globes. They ascertained, as we have seen, the size of the earth by the measurement of a degree on her surface, determined the obliquity of the ecliptic, published corrected tables of the sun and moon fixed the length of the year, verified the precession of the equinoxes. The treatise of Albategnius on "The Science of the Stars" is spoken of by Laplace with respect; he also draws attention to an important fragment of Ibn-Junis, the astronomer of Hakem, the Khalif of Egypt, A.D. 1000, as containing a long series of observations from the time of Almansor, of eclipses, equinoxes, solstices, conjunctions of planets, occultations of stars—observations which have cast much light on the great variations of the system of the world. The Arabian astronomers also devoted themselves to the construction and perfection of astronomical instruments, to the measurement of time by clocks of various kinds, by clepsydras and sun-dials. They were the first to introduce, for this purpose, the use of the pendulum.

In the experimental sciences, they originated chemistry; they discovered some of its most important reagents—sulphuric acid, nitric acid, alcohol. They applied that science in the practice of medicine, being the first to publish pharmacopoeias or dispensatories, and to include in them mineral preparations. In mechanics, they had determined the laws of falling bodies, had ideas, by no means indistinct, of the nature of gravity; they were familiar with the theory of the mechanical powers. In hydrostatics they constructed the first tables of the specific gravities of bodies, and wrote treatises on the flotation and sinking of bodies in water. In optics, they corrected the Greek misconception, that a ray proceeds from the eye, and touches the object seen, introducing the hypothesis that the ray passes from the object to the eye. They understood the phenomena of the reflection and refraction of light. Alhazen made the great discovery of the curvilinear path of a ray of light through the atmosphere, and proved that we see the sun and moon before they have risen, and after they have set.

AGRICULTURE AND MANUFACTURE. The effects of this scientific activity are plainly perceived in the great improvements that took place in many of the industrial arts. Agriculture shows it in better methods of irrigation, the skillful employment of manures, the raising of improved breeds of cattle, the enactment of wise codes of rural laws, the introduction of the culture of rice, and that of sugar and coffee. The manufactures show it in the great extension of the industries of silk, cotton, wool; in the fabrication of cordova and morocco leather, and paper; in mining, casting, and various metallurgic operations; in the making of Toledo blades.

Passionate lovers of poetry and music, they dedicated much of their leisure time to those elegant pursuits. They taught Europe the game of chess; they gave it its taste for works of fiction—romances and novels. In the graver domains of literature they took delight: they had many admirable compositions on such subjects as the instability of human greatness; the consequences of irreligion; the reverses of fortune; the origin, duration, and end of the world. Sometimes, not without surprise, we meet with ideas which we flatter ourselves have originated in our own times. Thus our modern doctrines of evolution and development were taught in their schools. In fact, they carried them much farther than we are disposed to do, extending them even to inorganic or mineral things. The fundamental principle of alchemy was the natural process of development of metalline bodies. "When common people," says Al-Khazini, writing in the twelfth century, "hear from natural philosophers that gold is a body which has attained to perfection of maturity, to the goal of completeness, they firmly believe that it is something which has gradually come to that perfection by passing through the forms of all other metallic bodies, so that its gold nature was originally lead, afterward it became tin, then brass, then silver, and finally reached the development of gold; not knowing that the natural philosophers mean, in saying this, only something like what they mean when they speak of man, and attribute to him a completeness and equilibrium in nature and constitution—not that man was once a bull, and was changed into an ass, and afterward into a horse, and after that into an ape, and finally became a man."