The Waning of the Italian Renaissance

Around 1550 the Renaissance in Italy began to decline after some two hundred glorious years. The causes of this decline were varied. Perhaps at the head of the list should be placed the French invasion of 1494 and the incessant warfare that ensued. The worst disaster came in 1527 when unruly Spanish and German troops sacked the city of Rome, causing irreparable destruction. To the Italian political disasters was added a waning of Italian prosperity. The incessant warfare of the sixteenth century contributed to Italy’s economic hardships, and there was gradually less and less of a surplus to support artistic endeavors. A final cause was the Counter-Reformation. During the sixteenth century the Roman Church sought increasingly to exercise firm control over thought and art as part of a campaign to combat worldliness and the spread of Protestantism. The most notorious example of inquisitorial censorship of free intellectual speculation was the disciplining of the great scientist Galileo. In 1616 the Holy Office in Rome condemned the new astronomical theory that the earth moves around the sun as “foolish, absurd, philosophically false, and formally heretical.” In short order the Inquisition made Galileo recant his “errors” and sentenced him to house arrest for the duration of his life. Galileo was not willing to face death for his beliefs. Not surprisingly, Galileo was the last great Italian contributor to the development of astronomy and physics until modern times.

In conclusion, it should be emphasized that cultural and artistic achievement was by no means extinguished in Italy after the middle of the sixteenth century. On the contrary, an impressive new artistic style known as Mannerism was cultivated between about 1550 and 1600 by painters who drew on traits found in the later work of Michelangelo, and in the seventeenth century Mannerism was supplanted by the dazzling Baroque style, which was born in Rome under ecclesiastical auspices. Similarly, Italian music registered enormous accomplishments virtually without interruption from the sixteenth to the twentieth century. But the free spirit of Renaissance culture was found no more.
5. The Scientific Accomplishments of the Renaissance Period

Some extraordinarily important accomplishments were made in the history of science during the sixteenth and early seventeenth centuries, but these were not preeminently the achievements of Renaissance humanism. The educational program of the humanists placed a low value on science because it seemed irrelevant to their aim of making people more eloquent and moral. Nonetheless, at least two intellectual trends of the period did prepare the way for great new scientific advances. One was the currency of Neoplatonism. The importance of this philosophical system to science was that it proposed certain ideas, which would help lead to crucial scientific breakthroughs. It helped scientific thinkers to reconsider older notions which had impeded the progress of medieval science; in other words, it helped them to put on a new “thinking cap.” A second trend was very different: the growth in popularity of a mechanistic interpretation of the universe. Renaissance mechanism owed its greatest impetus to the publication in 1543 of the works of the great Greek mathematician and physicist Archimedes. Not only were his concrete observations and discoveries among the most advanced and reliable in the entire body of Greek science, but Archimedes taught the view that the universe operates on the basis of mechanical forces, like a great machine. Ultimately mechanism played an enormous role in the development of modern science because it insisted upon finding observable and measurable causes and effects in the world of nature.

One other Renaissance development which contributed to the rise of modern science was the breakdown of the medieval separation between the realms of theory and practice. The artists advanced mathematics and science when they investigated the laws of perspective and optics, worked out geometric methods for supporting the weight of enormous architectural domes, and studied the dimensions and details of the human body. In general, they helped make science more empirical and practically oriented than it had been earlier. Other reasons for the integration were the decline in prestige of the overly theoretical universities and a growing interest in alchemy and astrology among the leisured classes.

The actual scientific accomplishments of the Renaissance period were international in scope. The achievement par excellence in astronomy – the formulation and proof of the heliocentric theory that the earth revolves around the sun – was primarily the work of the Pole Copernicus, the German Kepler, and the Italian Galileo. Until the sixteenth century the Ptolemaic theory that the earth stands still at the center of the universe went virtually unchallenged in western Europe. Nicholas Copernicus (1473-1543), a Polish clergyman who inspired by the Neoplatonic assumptions that the sphere is the most perfect shape, that motion is more nearly divine than rest, and that the sun sits “enthroned” in the midst of the universe, “ruling his children the planets which circle around him,” worked out a new heliocentric theory. Specifically, in his On the Revolutions of the Heavenly Spheres, he argued that the earth and the planets move around the sun in concentric circles. His system itself was still highly imperfect.

It was Kepler and Galileo who ensured the triumph of Copernicus’s revolution in astronomy. Johann Kepler (1571-1630) studied astronomy in order to probe the hidden secrets of God. His basic conviction was that God had created the universe according to mathematical laws. Specifically, Kepler replaced Copernicus’s belief in uniform planetary velocity with his own “First Law” that the speed of planets varies with their distance from the sun, and he replaced Copernicus’s view that planetary orbits were circular with his “Second Law” that the earth planets travel in elliptical paths around the sun. He also argued that magnetic attractions between the sun and the planets keep the planets in orbital motion. That approach paved the way for the law of universal gravitation formulated by Isaac Newton at the end of the seventeenth century. Galileo Galilei (1564-1642) promoted acceptance for it by gathering further astronomical evidence. With a telescope which he manufactured himself and raised to a magnifying power of thirty times, he discovered the moons of Jupiter, the rings of Saturn, and spots on the sun. He was able also to determine that the Milky Way is a collection of celestial bodies independent of our solar system and to form some idea of the enormous distances of the fixed stars. These discoveries gradually convinced the majority of scientists that the main conclusion of Copernicus was true. The final triumph of this idea is commonly called the Copernican Revolution. Galileo is especially noted as a physicist for his law of falling bodies.

In the front rank among the physicists of the Renaissance were Leonardo da Vinci and Galileo. If Leonardo da Vinci had failed completely as a painter, his contributions to science would still entitle him to considerable fame. Not the least of these were his achievements in physics. Though he actually made few complete discoveries, his conclusion that “every weight tends to fall toward the center by the shortest way” contained the kernel of the law of gravity. In addition, he worked out the principles of an astonishing variety of inventions, including a diving board, a steam engine, an armored tank, and a helicopter.

The record of Renaissance achievements in medicine and anatomy is also a most impressive one. Attention must be called above all to the work of the German Theophrastus von Hohenheim, known as Paracelsus (1493-1541), the Spaniard Michael Servetus (1511-1553), and the Belgian Andreas Vesalius (1514-1564). The physician Paracelsus believed that spiritual rather than material forces governed the working of the universe. He relied on observation for his knowledge of diseases and their cures. Above all, his insistence on the close relationship of chemistry and medicine foreshadowed and sometimes directly influenced important modern achievements in pharmacology and healing. Michael Servetus, who practiced medicine for a living, discovered the lesser or pulmonary circulation of the blood, in an attempt to prove the veracity of the Virgin birth. He described how the blood leaves the right chambers of the heart, is carried to the lungs to be purified, then returns to the heart and is conveyed from that organ to all parts of the body. But Servetus had no idea of the return of the blood to the heart through the veins, a discovery that was made by the Englishman William Harvey in the early seventeenth century. Purely by coincidence the one sixteenth-century scientific treatise that came closest to rivaling in significance Copernicus’s work in astronomy, Vesalius’s On the Structure of the Human Body, was published in 1543, the same year that saw the issuance of Copernicus’s Revolutions of the Heavenly Spheres. Since Vesalius in the same work offered basic explanations of how parts of the body move and interact in addition to discussing and illustrating how they work, he is often counted as the father of modern physiology as well as the father of modern anatomy.

Chapter 6 THE SCIENTIFIC REVOLUTION AND ENLIHGTENMENT
The years between roughly 1660 and 1789, which witnessed the prevalence of absolutism in western Europe, witnessed as well the most important mutation in all of European intellectual and cultural history to occur between the Middle Ages and the present. Just as the sweep of fresh winds can greatly change the weather, so in the last few decades of the 17th century the sweep of new ideas led to a bracing change in Europe’s “climate of opinion.” For purposes of analysis it is convenient to refer to two phases within the larger period: the triumph of the scientific revolution in the second half of the 17th century and the age of “Enlightenment” which followed for most of the 18th century. But without any doubt the same intellectual winds that swept into Europe during the later 17th century prevailed for well over a hundred years. Indeed, their influence is still felt today.

How did the new intellectual climate differ from the old? Concentrating on essentials, three points may be stressed. First, whereas medieval, Renaissance, and Reformation thinkers all assumed that past knowledge was the most reliable source of wisdom, the greatest thinkers from the 17th century onward rejected any obeisance to ancient authority and resolved to rely on their own intellects to see where knowledge would lead them. Making their motto “dare to know,” they stressed the autonomy of science and the free play of the mind in ways unheard of in the West since the golden age of Greece. Second, the new breed of thinkers believed strongly that knowledge was valueless if it could not be put to use. After the change in Europe’s climate of opinion in the late 17th century, all knowledge without practical value was belittled and thinkers from every realm of intellectual endeavor aimed directly or indirectly at achieving “the relief of man’s estate.” Finally, the new climate of opinion was characterized by the demystification of the universe. Around 1660 a mechanistic worldview swept away occultism. Thereafter nature was believed to work like the finest mechanical clock – consummately predictable and fully open to human understanding.

Why such a dramatic change in basic patterns of thought took place when it did will long remain a subject for speculation. Certainly the prior Scholastic stress on human rationality and the Renaissance reacquisition of classical Greek texts helped to bring European thought to a scientific threshold. Probably the most direct causes of the intellectual mutations, however, were the twin challenges to conventional assumptions introduced in the 16th century by the discovery of the New World and the realization that the earth revolves around the sun. At first many thinkers experienced a sense of intellectual crisis. Some took refuge in skepticism, others in relativism, and others in a return to blind faith. Speaking for several generations, the poet John Donne lamented in 1611 that “new philosophy calls all in doubt, the element of fire is quite put out, the sun is lost, and the earth, and no man’s wit can well direct him where to look for it … ‘tis all in pieces, all coherence gone.” But just as Europe surmounted its early-modern political crisis around 1660, so did it surmount its intellectual one, above all because the last stages of a profound scientific revolution gave a new, completely convincing “coherence” to things. As Alexander Pope wrote in the early 18th century, almost as if in response to Donne: “Nature and Nature’s Law’s lay hid in night:/ God said, Let Newton Be! And all was light.”
1. The Scientific Revolution

Even though Europe did not begin to resolve its intellectual crisis until about 1660 the groundwork for that resolution was prepared earlier in the 17th century by four great individuals. Kepler and Galileo – both practicing scientists – have been discussed earlier; they removed all doubts about the Copernican heliocentric theory of the solar system and helped lead the way to Sir Isaac Newton’s theory of universal gravitation. As for Bacon and Descartes, their main achievements were not in the realm of original scientific discovery but rather in propagating new attitudes toward learning and the nature of the universe.

Sir Francis Bacon (1561-1626), lord chancellor of England, was also an extremely influential philosopher of science. In Bacon’s view, expressed most fully in his Novum Organum (New Instrument) of 1620, science could not advance unless it departed entirely from the inherited errors of the past and established “progressive stages of certainty.” For Bacon this meant proceeding strictly on the basis of empirical knowledge (knowledge gained solely by the senses) and by means of the “inductive method.” Insisting that “the corruption of philosophy by superstition and an admixture of theology … does the greatest harm,” and that thinking people thus should be “sober-minded, and give to faith that only which is faith’s,” Bacon advocated the advancement of learning as a cooperative venture proceeding by means of meticulously recorded empirical experiments. Collective scientific research and observation would produce useful knowledge and result in bettering the human lot. Much of Bacon’s ideology is vividly evoked in the cover illustration of his Novum Organum.

Bacon’s later contemporary, the French philosopher Rene Descartes (1596-1650), agreed with him on two points: that all past knowledge should be discarded, and that the worth of any idea depended on its usefulness. Yet unlike the empiricist Bacon, Descartes was a rationalist and an apostle of mathematics. In his Discourse on Method (1637), Descartes explained how, during a period of solitude, he resolved to submit all inherited doctrines to a process of systematic doubting because he knew that the “strangest or most incredible” things had previously been set down in learned books. Taking as his first rule “never to receive anything as a truth which [he] did not clearly know to be such,” he found himself doubting everything until he came to the recognition that his mere process of thought proved his own existence (“I think, therefore I am”). Thereupon making rationality the point of departure for his entire philosophical enterprise, Descartes rebuilt the universe on largely speculative grounds that differed in almost every detail from the universe conceived by the Greeks, yet conformed fully to the highest principles of human rationality as expressed in the laws of mathematics. He was confident that “natural processes almost always depend on parts so small that they utterly elude our senses.”

Predictably, the details of Descartes’ scientific system are now regarded as mere curiosities, but the French philosopher nonetheless was enormously influential in aiding the advance of science and in creating a new climate of opinion for several reasons. First of all, it did contribute to the discrediting of all the faulty science of the ancients. Then too, Descartes’ stress on mathematics was salutary because mathematics has indeed proven to be an indispensable handmaiden to the pursuit of natural science. But undoubtedly Descartes’ single most influential legacy was his philosophy of dualism, accordingly to which God created only two kinds of reality – mind and matter. In Descartes’ view, mind belonged to man alone, and all else was matter. Thus he insisted that all created existence beyond man – organic and inorganic alike – operated solely in terms of physical laws, or the interplay of “extension and motion.” Indeed, Descartes thought that man himself was a machine –a machine equipped with a mind. From this it followed that the entire universe could be studied objectively. Moreover, all apparent atributes of matter, such as light, color, sound, taste, or smell, which had no “extension” were to be classified as mere subjective impressions of the human mind unfit for proper scientific analysis. Based on such assumptions the pursuit of science could be dispassionate as never before.

Roughly speaking, for about a century after the work of Bacon and Descartes the English scientific community was Baconian and the French Cartesian. This is to say that the English concentrated primarily on performing empirical experiments in many different areas of physical science leading to concrete scientific advances, whereas the French tended to remain more oriented toward mathematics and philosophical theory. Among the numerous great 17th-century English laboratory scientists were the physician William Harvey (1578-1657), the chemist Robert Boyle (1627-1691), and the biologist Robert Hooke (1635-1703). Harvey was the first to observe and describe the circulation of the blood through the arteries and back to the heart through the veins. Similarly committed to empirical experiment, Boyle used the air pump to establish “Boyle’s law” – namely, that under constant temperature the volume of a gas decreases in proportion to the pressure placed on it. Boyle also was the first chemist to distinguish between a mixture and a compound. As for Hooke, he is best known for having used the microscope to discover the cellular structure of plants. Meanwhile, in France, Descartes himself pioneered in analytical geometry, Blaise Pascal worked on probability theory and invented a calculating machine before his conversion to religion.

The dichotomy between English Baconianism and French Cartesianism, however, breaks down when one approaches the man commonly considered to have been the greatest scientist of all time, Sir Isaac Newton (1642-1727). Newton was a towering genius who drew on both the Baconian and Cartesian heritages. In the sharpest opposition to Descartes, Newton refused to dismiss the phenomenon of light as a mere subjective impression of “mind.” Instead, he demonstrated that light behaves differently when filtered through different media, and hence offered an interpretation of light as a stream of particles that solidly established optics as an empirical branch of physics. Yet, Newton thoroughly approved of Descartes’ stress on mathematics, and once in a burst of purely theoretical inspiration discovered the infinitesimal calculus.

Of course Newton’s supreme accomplishment lay in his formulation of the law of universal gravitation, which, as expressed in his monumental Latin Principia_Mathematica'>Principia Mathematica (Mathematical Principles of Natural Philosophy) of 1687, integrated Copernican astronomy with Galileo’s physics. In the Principia Newton broached the two major scientific questions of his day: (I) What keeps the heavy earth in motion? And (II) why do terrestrial bodies tend to fall to the earth’s center whereas planets stay in orbital motion? In the early 17th century Kepler had already suggested the possibility of mutual attractions between all bodies in the solar system that kept the earth and other planets moving, but the Cartesians attacked this explanation. Newton returned to consider Kepler’s theory of mutual attractions, and uniting Baconian observations with Cartesian mathematics, arrived at a single law of universal gravitation according to which “every particle of matter in the universe attracts every other particle with a force varying inversely as the square of the distance between them and directly proportional to the product of their masses.” Newton’s law was so reliable that it was employed immediately to predict the ebb and flow of tides.

Historians of science consider Newton’s law of gravity to be “the most stupendous single achievement of the human mind,” finding that “no other work in the whole history of science equals the Principia either in originality and power of thought or in the majesty of its achievement.” Certainly the publication of the Principia was the crowning event of the scientific revolution because it confirmed the most important astronomical and physical theories previously set forth by Copernicus, Kepler, and Galileo, and resolved beyond quarrel the major problems that Copernicus’s heliocentric theory had created. Since Newton’s accomplishment proved inspirational to researchers in many other fields, scientific work advanced steadily after 1687. Thinkers in all areas could proceed with their work confident that science rather than superstition was the new order of the day.
2. The Foundations of the Enlightenment

Although the presuppositions for the Enlightenment were set by the triumph of the scientific revolution in the late 17th century, the Enlightenment itself was an 18th-century phenomenon, lasting for close to the entire century until certain basic Enlightenment postulates were challenged around 1790 by the effects of the French Revolution and the new movement of romanticism. Of course not every thinker who lived and worked in the 18th century was equally “enlightened.” Some, such as the Italian philosopher of history G. B. Vico (1668-1744), were thoroughly opposed to everything the Enlightenment stood for, and others, most notably Jean Jacques Rousseau (1712-1778), accepted certain Enlightenment values but sharply rejected others. Moreover, patterns of Enlightenment ideology tended to vary from country to country and to change over the course of the century. Yet, despite these qualifications, most thinkers of the 18th century definitely shared the sense of living in an exacting new intellectual environment in which “the party of humanity” would prevail over traditionalism and obscurantism by dint of an unflinching commitment to the primacy of the intellect.

Most Enlightenment thought stemmed from three basic premises: (1) the entire universe is fully intelligible and governed by natural rather than supernatural forces; (2) rigorous application of “scientific method” can answer fundamental questions in all areas of inquiry; and (3) the human race can be “educated” to achieve nearly infinite improvement. The first two of these premises were products of the scientific revolution and the third primarily an inheritance from the psychology of John Locke.

Regarding the substitution of a natural for a supernatural worldview, explanations must start with the euphoria which greeted Isaac Newton’s discovery of a single law whereby all motion in the heavens and earth became intelligible and predictable. This is not to say that the Enlightenment abandoned belief in the existence of God: to the contrary, most adhered to a religious outlook known as Deism. Expressed in the language of the Deists themselves, God was the “divine clockmaker” who, at the beginning of time, constructed a perfect timepiece and then left it to run on with predictable regularity.

As for the second Enlightenment premise, the accomplishments of the scientific revolution inspired a deep sense of assurance that “scientific method” was the only valid means for pursuing research in all areas of human inquiry. Since most scientific work was still simple enough to be understood by amateurs, European aristocrats and prosperous people in all walks of life began to dabble in “research” in the hope of participating in some new scientific breakthrough. Their enthusiasm for following the latest developments in scientific research led them to patronized the work of truly gifted scientists and contributed to creating an atmosphere wherein science was prized as humanity’s greatest attainment. Inevitably, in turn, such an atmosphere was conducive to an assumption which became dominant in the course of the 18th century – that scientific method was the only proper means for studying human affairs as well as natural phenomena. As the English poet Alexander Pope stated in his Essay on Man of 1733, “the science of human nature [may be] like all other sciences reduced to a few clear points,” and Enlightenment thinkers became determined to learn exactly what those “few clear points” were.

It must be stressed, however, that if most thinkers of the Enlightenment also believed that human conduct was not immutable but highly perfectible. In this they were inspired primarily by the psychology of John Locke (1632-1704), who was not only a very influential political philosopher, but also the formulator of an extremely influential theory of knowledge. In his Essay Concerning Human Understanding (1690) Locke rejected the hitherto dominant assumption that ideas are innate, maintaining instead that all knowledge originates from sense perception. According to him, the human mind at birth is a “blank tablet” upon which nothing is inscribed: not until the infant begins to experience things, that is, to perceive the external world with its senses, is anything registered on its mind. From this point of departure, Enlightenment thinkers concluded that environment determines everything. It followed that all people could be educated to become the most perfect, and that there were no limits to the potentialities for universal human progress. A few Enlightenment thinkers became so optimistic as to propose that all evil might be eradicated from the world, since whatever evil existed was not the result of some divine plan but only the product of a faulty environment that humans had created and humans could change.