Three Scientific Revolutions: How They Transformed Our Conceptions of Reality
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It was the Ptolemies who created its famous Museum that became the center of research in astronomy, mathematics, physics, engineering, anatomy, and medicine that eventually eclipsed Plato’s Academy and Aristotle’s Lyceum as the world’s center of learning. Adjacent to the Museum was the equally famous Royal Alexandrian Library that, according to the earliest account, was built during the reign of Ptolemy I Sorter (ca. 367–ca. 283 BCE), but organized by a prestigious student of Aristotle, Demetrius of Phaleron, that became the greatest library of the ancient world.
This period has been referred to as the “first great age of science,” surpassing the achievements of the Hellenic Greeks because their scientific investigations and discoveries were less speculative, conforming more to and thus the forebear of, modern classical science.9 Unlike Aristotle whose scientific works have all been disproved despite their profound historical influence, some of the scientific and mathematical contributions of the Hellenistic thinkers are still valid. Listed in their chronological order they include Euclid, the most famous of the Alexandrian mathematicians who wrote in the third century BCE. Though he began his mathematical studies in Plato’s Academy, he wrote his famous Elements of Geometry while in Alexandria, acclaimed as the most widely read book in history except for the Bible and extolled by the young Einstein as the model for scientific reasoning.
The second most renowned mathematician, also of the third century BCE, was Archimedes who lived in Syracuse, Sicily, but visited Alexandria two years after the death of Euclid. His outstanding contributions include his method of exhaustion anticipating differential calculus, discovery of the law of specific gravity, and formulation of the principles underlying many technological inventions such as the lever, the pulley, and the tubular screw used to pump water from wells and mines. It is reputed that his pulleys were so powerful that during the siege of Syracuse he was able to attach them to the bows of Roman ships lifting and twisting them out of the sea casting the terrified crew overboard. A third famous Hellenistic mathematician was Hipparchus of Nicaea, who lived in the second century BCE and is especially known for founding plane and spherical trigonometry.
We previously discussed the contributions of Aristarchus of Samos, who wrote in the third century BCE and is referred to as the “Hellenistic Copernicus.” Yet the only evidence we have of this is in Archimedes’ description in the “The Sand-Reckoner.”
Now you [Kind Gelon] are aware that “universe” is the name given by most astronomers to the sphere whose centre is the centre of the earth. . . . But Aristarchus of Samos brought out a book consisting of some hypotheses. . . . [such as] that the fixed stars and the sun remain unmoved, that the earth revolves about the sun in the circumference of a circle, the sun lying in the middle of the orbit.10 (Brackets added)
Although partially preceded by the Pythagoreans and Philolaus, the quote’s introduction of the heliocentric worldview by Aristarchus is one of the most striking in the history of astronomy.
The other significant astronomer previously referred to is Hipparchus whose major works were written in Alexandria. His varied contributions included the design of the astrolabe, an authoritative star chart, recognition of the precession of the equinoxes, and very exact measurements of the moon’s diameter and distance from the earth. However, as important as these previous contributions were, it was Ptolemy’s Almagest (the title of his major work later given by the Arabs) written in Alexandria in the second century CE whose astronomical system with its epicycles, eccentrics, and equants, to accommodate the astronomical observations that did not fit the spherical orbits and uniform motion of Eudoxus’ celestial system, that eclipsed Aristarchus’ heliocentrism and that prevailed until its rejection by Copernicus.
But, it was Eratosthenes, the famous librarian of Alexandria in the third century BCE, having acquired a notable reputation as an astronomer, mathematician, geographer, and philologist, who rivaled Aristotle as “the most learned man of antiquity.” Known for his invention of the “Sieve of Eratosthenes” for deriving prime numbers and his astute geometrical studies, his mathematical gifts facilitated his remarkable geographical discoveries. He drew the most accurate map of the world for the time showing the circumference of the earth divided into latitudes and longitudes, proposed that the oceans were so united that it would be possible to reach India by sailing west and, most importantly, introduced an ingenious mathematical method for measuring the circumference of the earth within an accuracy of 200 miles.
Another amazing researcher in Alexandria of the third century BCE was Herophilus of Chalcedon, one of the first to practice human dissection and consequently is considered the outstanding anatomist of ancient Greece. Among his discoveries was that the arteries carried blood from the heart to all parts of the body, the usefulness of the pulse in diagnosing various illnesses, and that by dissecting the brain various bodily functions could be correlated with specific brain regions, a remarkable discovery for the time. He was succeeded by Erasistratus, who is said to have practiced vivisection in Alexandria also in the third century. He, too, is famous for having discovered the functions of various body parts, such as the valves in the heart and distinguishing between the arteries and the veins detecting their interconnection. (For more on ancient medicine see volume one of my book From Myth to Modern Mind: A Study of the Origins and Growth of Scientific Thought.)
Still, despite the belief that revealed scripture was far superior to scientific knowledge, the best known of the physiologists is Galen of Pergamum, who in his youth studied in Alexandria and other centers of learning acquiring the vast knowledge of medicine for which he is famous and then settling in Rome for the rest of his life in the second century CE. Three reasons account for his prominence: (1) his encyclopedic knowledge; (2) that while most of the works of the previous Ionian scholars were lost in the various fires that destroyed the Royal Library in Alexandria his, fortunately, were preserved; and (3) that his own physiological research was so advanced that it prevailed until replaced by the work of Andreas Vesalius in the sixteenth century.
His major achievement was his description of the physiological organs and functions integrating the circulatory, respiratory, and nutritive systems. He described how the “cosmic pneuma” was inhaled through the trachea, carried to the lungs, and then transmitted by the Vena arterials to the left cavity of the heart where it was mixed with the blood. The blood itself was derived from nutriment taken by the portal vessel from the intestines to the liver where it was converted to venous blood by combining with a second spirit or pneuma, called “natural spirit,” which is viewed as essential for life.
The combination of natural spirit and nutriment composing the venous blood in the liver is then dispersed by the veins throughout the venous system. When some of this venous blood is carried to the right cavity of the heart it divides into two portions, the larger discharging its impurities back into the Vena arterials where it is carried to the lungs and breathed out with the remaining purified portion returning to the venous system. This smaller portion slowly flows through tiny vessels passing the septum dividing the two sides of the heart entering drop by drop into the left side. There they mix with the outside pneuma or natural spirit entering the trachea producing a third, higher type of pneuma, the “vital spirit”: the terms ‘vitalism,’ ‘vital principle,’ and Bergson’s élan vitale also were used in the late nineteenth and early twentieth centuries to counter the claim that strictly mechanistic or physiological theories could fully explain evolution. The dark venous blood is then transformed into a bright arterial blood and dispersed via the arteries throughout the body and to the base of the brain where it is activated by another pneuma, an “animal spirit,” animating the body.
This extraordinary explanation was facilitated by his dissection of the Barbary apes whose anatomy closely resembles humans. It also illustrates the remarkable progress made in devising better investigative methods and more accurate scientific explanations since Aristotle (who located consciousness i
n the heart). An ardent teleologist, Galen believed that everything was ordained by God, which motivated his research and is one reason his system was so popular during the Middle Ages.
Brief mention should be made of three other contributors to Alexandrian research. First is Hero or Heron of Alexandria who lived in the first century CE and is known for his ingenious technological inventions in pneumatics and mechanics. These include a globe with attached jets through which the steam from an underlying boiling caldron in successively passing through the jets causes their rotation, a precursor of the steam engine; a cogwheel turned by a twisted screw; multiple pulleys; and a Dioptra for measuring the angles and heights of distant objects.
Second is Rufus of Ephesus, who also lived in the first century CE and made crucial advances in understanding the structure and functioning of the eyes, some of his nomenclature still used today. Third is Diophantus, who lived in the second century CE and is recognized for his contributions to algebra and for introducing signs for minus, equality, unknowns, and powers used to solve various algebraic functions. While these were important discoveries, progress in algebra remained far behind the advances in geometry made by Euclid and those in trigonometry made by Hipparchus of Nicaea.
Had these inquiries continued, modern classical science would not have had to wait nearly two millennia before its resumption. Despite the Romans’ extraordinary gifts for engineering and architecture as seen in their splendid aqueducts, temples, baths, and colosseums; for creating some of the world’s greatest literature in the writings of Cicero, Virgil, Horace, Ovid, and Pliny; for their remarkable artistic talents displayed in the lovely frescoes in Livia’s villa and recovered in Pompeii and Etruria; and for their interest in reading resulting in their creating beautifully designed public libraries throughout the empire, one cannot cite a single outstanding mathematician or natural philosopher who was not Greco-Roman.
After the rise of Christianity and the transfer of the Roman empire by Constantine to Constantinople in 330 CE, the Christian belief that the primary goal in life is gaining salvation and deliverance into heaven replaced attempts to understand and improve the world we live in. If all is ordained by God, gaining God’s help by prayer would be more effective in controlling events than discovering their natural causes as in the saying, “Inshallah” or “God willing.” As Ambrose, one of the Patristic Fathers and Bishop of Milan, declared: “To discuss the nature and position of the earth does not help us in our hope of the life to come. It is enough to know what Scripture states. . . .”11 Or as St. Augustine, an early church father and Bishop of Hippo, reiterated: “‘Nothing is to be accepted except on the authority of Scripture, since greater is that authority than all powers of the mind.’”12 But the supremacy of Christianity over paganism began with the zealous Christian Roman ruler Theodosius the Great in 391 CE who issued edicts prohibiting pagan rituals and public ceremonies with the intent of eradicating paganism.
Theophilus of Antioch began applying the edicts of Theodosius directing ruthless gangs of Christians to assault the pagans, along with destroying their sanctuaries, monuments, and statues. Cyril, the nephew and successor of Theophilus, turned the wrath of these Christians against the Jews, ordering their expulsion from Alexandria, but, fortunately, he was opposed by Orestes, governor of Alexandria.
An especially horrific example of the oppressive cruelty was the vile murder of the renown and revered scholar Hypatia. The daughter of a mathematician, she became famous as a mathematician in her own right, along with attaining an outstanding reputation in music, astronomy, and philosophy. Unlike women at the time who where secluded in their homes, she was one of Alexandria’s most admired personages: very beautiful as well as learned and refined, she rode around the city in a chariot. But admirable as this reputation was, it led to her vicious execution.
Opposed to her pagan notoriety, in March of 415, upon returning home, a gang of Cyril’s followers attached her and took her to a church, where “she was stripped of her clothing, her skin was flayed off with broken bits of pottery. The mob then dragged her corpse outside the city walls and burned it. Their hero Cyril was eventually made a saint.”13 So much for the Christian “brotherhood of man.” The period when Christianity was dominant has justly been called the dark ages. In fact, the Inquisition in Spain during the fifteenth century was one of the most unjust, terrifying, and fiendish in history.
Having described the transition from the earlier mythological, theogonic worldview to the first awaking of the possibility of a more rational understanding of the universe and human existence, we turn now to the second revolution when science began replacing both religion and philosophy.
Chapter II
THE SECOND TRANSITION OWING TO THE CREATION OF MODERN CLASSICAL SCIENCE
The second revolution that transformed our conception of reality followed the Renaissance with the resurgence of classical Greek science in the sixteenth and seventeenth centuries and extended to the Age of Enlightenment in the eighteenth century. Realizing the failures of such pseudosciences as alchemy and astrology, it also represented the demise of the authority of the Catholic Church because of the increasing confidence in the new scientific advances disclosing and refuting the incredible nature of Christian beliefs. It also replaced Aristotle’s mistaken conception that metaphysics was a separate philosophical discipline that could transcend scientific inquiry by attaining a truer conception of reality that sustained such later philosophical systems as absolute idealism until it was eventually superseded by science.
Though it was mainly Aristotle’s insistence that observable evidence was the primary basis of natural explanations that originally replaced mythical or religious creation myths, it gradually became clear that sensory evidence alone was insufficient to explain our ordinary experience of natural phenomena and their underlying causes. Three developments especially led to the awareness of the deceptive nature and explanatory limitations of sensory perceptions, along with the necessity of revising and supplementing them with more exact laws and a different conceptual system.
These developments were: (1) more exact astronomical measurements with the astrolabe and sextant; (2) technological advances in observation with the invention of the telescope and the microscope; and (3) the realization that empirical generalizations—such as the Aristotelian law of free fall or Eudoxus’ conception of the circular orbits and uniform motion of the planets—must be replaced by more exact observations, experimental investigations if possible, and testable explanations. This culminated in replacing the geocentric perspective with the heliocentric cosmology; the discovery of more exact astronomical and terrestrial laws of motion; and the rejection of the age-old distinction between the celestial and terrestrial worlds with the recognition of a microworld of particles and formulation and adoption of Newton’s corpuscular-mechanistic worldview.
This essentially began with Copernicus’s magisterial work, De revolutionibus orbium coelestium (On the Revolutions of Heavenly Spheres), containing numerous diagrams, mathematical tables, and charts depicting the revolutions of the planets to show the incongruities of the geocentric cosmology and proposing a more harmoniously integrated system. Confirming the resurgence of an interest in Classical Greek science, Copernicus states in his Preface and Dedication to Pope Paul III that since the ancient Pythagoreans had considered that the earth moved,
when I had meditated upon this lack of certitude in the traditional mathematics concerning the composition of movements of the spheres of the world . . . I finally discovered by the help of long and numerous observations that if the movements of the other wandering stars are correlated with the circular movement of the Earth [around the Sun], and . . . are computed in accordance with the revolution of each planet, not only do all their phenomena follow from that but . . . this correlation binds together so closely the order and magnitudes of all the planets and of their spheres or orbital circles and the heavens themselves that nothing can be shifted around in any part of them without d
isrupting the remaining parts and the universe as a whole.14 (brackets added)
One can discern one revolutionary feature of his “hypotheses” in the fact that it was “the lack of certitude in the traditional mathematics” that he cites as the justification for attributing motions to the earth despite its opposition to ordinary experience, showing the increasing influence of mathematics in scientific inquiry (an affirmation of Plato over Aristotle later extolled by Galileo). It also shows a new awareness of the tremendous complexity of the problems, along with the required freedom to explore alternative possibilities offered by the new evidence, again rejecting the unwarranted injunctions of the Catholic Church.
Thus began the dismantling of the ancient model of the universe as a celestial sphere composed of an aethereal substance bounded by the sphere of the fixed stars revolving around the stationary central earth. Within this sphere the seven planets, Moon, Mercury, Venus, Sun, Mars, Jupiter, and Saturn, in that ascending order, revolved in heavenly spheres in uniform circular motion at extended distances. Their individual motions were variously attributed to intelligences (Aristotle), to having been created by God in their respective orbits and endowed with their uniform circular motions (Christians), or to their having souls as Kepler originally believed and then replaced by a materialistic “clockwork” system driven by gravity, further emended by Galileo and Newton.