The Story of Science
Civilizations Past And Present
The European Dream Of Progress And Enlightenment
Impact Of The Scientific Revolution
Science, Art, And Philosophy In The Eighteenth Century
Introduction
In the eighteenth century, while royal absolutism faced serious problems,
many learned and thoughtful Europeans held a shining vision of the future.
They saw civilization advancing toward a future of diminished ignorance,
brutality, and exploitation. Most believed that human reason, having finally
reached its true potential, would bring the downfall of Old Regimes, which
were being recognized as violating recently discovered laws of nature. Unlike
Saint Augustine, who had described a City of God in the next world, many
eighteenth-century thinkers confidently anticipated a happy earthly community.
In the words of American historian Carl Becker they dreamed of a beautiful but
terrestrial "heavenly city." ^1
[Footnote 1: Carl L. Becker, The Heavenly City of the Eighteenth-Century
Philosophers (New Haven: Yale University Press, 1932), pp. 49, 129.]
Such ideas arose partially from social experience. European wealth was
expanding rapidly, in comparison with all other societies. In fashionable
European salons, philosophers and artists rubbed elbows with bored nobles and
sons of enterprising bankers, who indulged in clever criticism of the Old
Regime as a form of recreation. But a new popular philosophy appealed directly
to the vested interests of the middle classes. By emphasizing the systematic
regularity of nature, it automatically denied justification for most royal
authority. The laws of nature promised to replace the laws of monarchs, along
with their state churches, idle nobles, arbitrary courts, high taxes, and
mercantilist control of business.
The concern for special interests was one source of the new vision, but
it also rose from an intellectual stimulus. In the late seventeenth century,
Europeans yearned for order, which scientists were finding throughout the
universe. New discoveries in astronomy, physics, chemistry, and even biology
strongly suggested that nature, from the smallest particle to the most distant
stars, was an interlocking mechanism of harmoniously working parts. Here,
apparently, was the simple answer to an everlasting search for certainty and
the immediate origin of optimistic hopes for humanity.
Impact Of The Scientific Revolution
By the later seventeenth century, science had won general acceptance and
was beginning to dominate the European mind. The victory had been hard won.
When during the late Renaissance the Italian universities and a few northern
Europeans made advances in anatomy, medicine, and astronomy, their work was
considered inconsequential or irreligious. Later scientists who persisted in
taking their own conclusions seriously were either ignored or persecuted. Even
the work of Copernicus was regarded more as mathematical exercise than a
description of reality. This situation changed drastically after Sir Isaac
Newton (1641-1727) expressed his universal law in mathematical terms and
supported its validity by empirical results.
The Early Pioneering Era Of Modern Science
The most notable of the scientific pioneers were astronomers, whose field
of study was peculiarly suited to the new scientific method. As it was
developed in the sixteenth century, this methodology involved a combination of
two approaches, each depending upon human reason, with differing applications.
The deductive approach started with self-evident truths and moved toward
complex propositions, which might be applied to practical problems. It
emphasized logic and mathematical relationships. The inductive approach
started with objective facts, that is, knowledge of the material world. From
facts, proponents of induction sought to draw valid general conclusions. In
the past, the two procedures had often been considered contradictory. Early
European astronomers were uniquely dependent on both kinds of reasoning.
The French scholar-mathematician Rene Descartes (1596-1650) initiated a
new and critical mode of deduction. In his famous Discourse on Method (1627),
Descartes rejected every accepted idea that could be doubted. He concluded
that he could be certain of nothing except the facts that he was thinking and
that he must therefore exist. From the basic proposition, "I think, therefore
I am," Descartes proceeded in logical steps to deduce the existence of God and
the reality of both the spiritual and material worlds. ^2 He ultimately
conceived a unified and mathematically ordered universe, which operated as a
perfect mechanism. In the Cartesian physical universe, supernatural processes
were impossible; everything could be explained rationally, and preferably in
mathematical terms.
[Footnote 2: Rene Descartes, Discourse on Method (New York: Liberal Arts
Press, 1956), pp. 20-26.]
Descartes' method was furthered by discoveries in mathematics, and the
method, in turn, popularized the study of the subject. Descartes' work
coincided with the first use of decimals and the compilation of logarithmic
tables. The latter advance, by halving the time required to solve intricate
problems, may have doubled the effective influence of mathematics in the early
1600s. Descartes himself was successful in developing analytical geometry,
which permitted relationships in space to be expressed in algebraic equations.
Using such equations, astronomers could represent the movements of celestial
bodies in mathematical symbols. Astronomers received further aid later in the
century when Sir Isaac Newton in England and Gottfried von Leibniz (1646-1716)
in Germany independently perfected differential calculus, or the mathematics
of infinity, variables, and probabilities.
The other great contributor to the theory of scientific methodology in
this era was the Englishman Sir Francis Bacon (1561-1626). At a time when
traditional systems of thought were crumbling, Bacon set forth a program
extolling human reason, as applied to human sensory experiences. He advocated
an inductive approach, using systematically recorded facts derived from
experiments. These facts, he believed, would lead toward tentative hypotheses,
which could then be tested by fresh experiments under new conditions.
Ultimately, the method would reveal fundamental laws of nature. Bacon's ideas,
outlined in his Novum Organum (1626), were the first definitive European
statement of inductive principles. ^3
[Footnote 3: Francis Bacon, Novum Organum (London: William Pickering, 1844),
pp. 13-17, 84-89.]
The inductive approach became even more practical with the remarkable
improvement of scientific instruments. Both the telescope and the microscope
came into use at the opening of the seventeenth century. Other important
inventions included the thermometer (1597), the barometer (1644), the air pump
(1650), and the pendulum clock (1657). With such devices, scientists were
better able to study the physical universe.
Using both mathematics and observation, early astronomers before 1600
prepared the way for a scientific revolution. This was certainly true after
1543, the year of Copernicus' death and the publication of his famous book, On
the Revolutions of the Heavenly Spheres. In the book, Copernicus posited a
theory directly opposed to the traditional Ptolemaic explanation for passing
days and the apparent movement of heavenly bodies. The old geocentric theory
had assumed that the sun, the planets, and the stars all circled the earth.
The new heliocentric theory postulated the sun as the center, around which the
sun and planets moved.
Copernicus offered his idea as merely mathematical theory. By the end of
the century, However, Tycho Brahe (1546-1601), a Danish astronomer, aided by
his accomplished sister, Sophia (1556-1643), had recorded hundreds of
observations that pointed to difficulties in the Ptolemaic explanation. Brahe
even attempted, without much success, to find a compromise between the
Ptolemaic and Copernican systems by postulating that the planets moved about
the sun while the latter orbited the earth. This proposition raised even more
problems and therefore met with little acceptance.
Brahe's data were used by his former assistant, the brilliant German
mathematician, Johannes Kepler (1571-1630), to support the Copernican theory.
While working mathematically with Brahe's records on the movements of Mars,
Kepler was ultimately able to prove that the planet did not move in a circular
orbit but in an ellipse. He also discovered that the paces of the planets
accelerated when they approached the sun. From this he concluded that the sun
might emit a magnetic force that directed the planets in their courses. The
idea was not yet confirmed by a mathematical formula, but that would soon be
achieved by Newton, using Kepler's hypothesis. Even in their own time,
however, Kepler's laws of planetary motion almost completely undermined the
Ptolemaic theory.
During the early seventeenth century, growing acceptance of the
heliocentric theory precipitated an intellectual crisis affecting organized
religion, particularly the Catholic church. Medieval Catholicism had accepted
Aristotle on physics and Ptolemy on astronomy. The church now felt its
authority and reputation challenged by the new ideas. Copernicus and Brahe had
both evaded the issue by purporting to deal only in mathematical speculations.
Kepler and others of his time became increasingly impatient with this
subterfuge. The most persistent of these scientific rebels was the Italian
mathematician-physicist, Galileo Galilei (1564-1642).
Galileo discovered more facts to verify the Copernican theory, but as he
wrote to Kepler,
... up to now I have preferred not to publish,
intimidated by the fortune of our teacher Copernicus,
who though he will be of immortal fame to some, is yet
by an infinite number (for such is the multitude of fools)
laughed at and rejected. ^4
[Footnote 4: Quoted in Stillman Drake, Galileo at Work (Chicago: University of
Chicago Press, 1978), p. 41.]
In 1609, Galileo made a telescope, and with it he discovered mountains on the
moon, sunspots, the satellites of Jupiter, and the rings of Saturn. Having
published his findings and beliefs, he was constrained by the Church in 1616
to promise that he would "not hold, teach, or defend" the heretical Copernican
doctrines. After another publication, he was again hauled before a church
court in 1633. This time, he was forced to make a public denial of his
doctrines. Galileo was defeated, but by the end of the century the
heliocentric theory had won common acceptance.
Newton And The Law Of Gravitation
Great as were the contributions of Galileo and Kepler, their individual
discoveries had not been synthesized into one all-embracing principle that
would describe the universe as a unity. When Sir Isaac Newton achieved this
goal, the opponents of science, such as Galileo's persecutors, were
effectively silenced.
The notion of gravitation occurred to Newton in 1666, when he was only
twenty-four. According to his own later account, he hit on the idea while
sitting in thought under an apple tree. A falling apple roused him to wonder
why it, and other objects, fell toward the center of the earth and not
sideways or upward. There must be, he thought in a flash of insight, some
drawing power associated with matter. If this were true, he reasoned, the
drawing power was proportionate to quantity, which would explain why the
smaller apple, despite its own attracting force, was pulled to earth. In his
Principia (1687), Newton expressed this idea precisely in a mathematical
formula. The resulting law of gravitation states that all material objects
attract other bodies inversely according to the square of their distances and
directly in proportion to the products of their masses. Hundreds of
observations soon verified this principle, firmly establishing the validity of
scientific methods.
Not only had Newton solved astronomical problems defined by Kepler and
Galileo he had also confirmed the necessity of combining methods advocated by
Descartes and Bacon. In the Principia, Newton stressed the importance of
supplementing mathematical analysis with observation. Final conclusions, he
insisted, must rest on solid facts; on the other hand, any hypothesis, no
matter how mathematically plausible, must be abandoned if not borne out by
obsevation or experimentation.
Newton had also confirmed the basic premise of modern science that all
nature is governed by laws. Indeed, his own major law was applicable to the
whole universe, from a speck of dust on earth to the largest star in outer
space. The magnitude of this idea - that is, the concept of universal laws -
was almost infinitely exciting and contagious. Within decades it had spread
throughout the Western world and had been applied in every area, including
human relations.
The Widening Scope Of Scientific Study
The impressive achievements of astronomers, climaxed by Newton's amazing
revelations, encouraged scientific interest and endeavors in all related
fields. As science widened its scope, the first advances outside of astronomy
came in physics and physiology. Both fields owed much to earlier influences
from Italian universities; both also reflected the new mechanistic ideas so
prevalent in astronomy. Chemistry, long affected by medieval alchemy, did not
reach maturity until the eighteenth century. By that time, in general biology,
apart from human anatomy and physiology, cellular studies and classification
systems had begun to develop, although there was as yet no comprehensive
evolutionary theory. Late in the century, however, geologists were suggesting
such a scheme.
In astronomy the period after Newton was a time of elaboration and
"filling in" the main outline, rather than one of new beginnings. A possible
exception was the brilliant French astronomer-mathematician, Pierre Laplace
(1749-1827), who has been called the Newton of France. Although a leading
disciple of Newton, Laplace went beyond his master. Newton believed that God
tended the universal machine to compensate for irregularities, but Laplace
demonstrated that apparent inconsistencies, such as comets, were also governed
by mathematical laws. Laplace is best known for his nebular hypothesis, which
maintained that our sun, once a gaseous mass, threw off the planets as it
solidified and contracted. Until recently, this hypothesis was widely
accepted.
Despite their lack of opportunities for scientific education, a number of
women became involved in astronomical studies during the eighteenth century.
In France, Emilie du Chatelet (1706-1749), the sometime mistress and lifelong
friend of Voltaire, translated the Principia, helping introduce Newton among
the French philosophes. Maria Kirch (1670-1720), while assisting her husband,
Gottfried, the royal astronomer in Berlin, discovered the comet of 1702. After
her husband's death, she published their observations, which were widely read.
Caroline Herschel (1750-1848), a native of Hanover working with her brother
William in England, helped build huge telescopes, shared the discovery of 2500
new nebulae, and by herself found a number of new comets. The Herschels' work
demonstrated that Newtonian principles applied to distant stars, outside the
solar system.
In physics, the field most closely related to astronomy, Galileo was the
pioneer. He defined the law of falling bodies, demonstrating that their
acceleration is constant, no matter what their weight or size. His experiments
also revealed the law of inertia: a body at rest or in motion will remain at
rest or continue moving (in a straight line at constant speed) unless affected
by an external force. In addition, he showed that the path of a fired
projectile follows a parabolic curve to earth, an inclination explained later
by the law of gravitation. Galileo made additional notable discoveries through
his studies of the pendulum, hydrostatics, and optics. His work was clarified
by two famous professors at the University of Bologna, Maria Agnesi
(1718-1799), in mathematics, and Laura Bassi (1700-1778), in physics.
Other physicists made significant contributions. For example, Newton and
the Dutch scientist, Christian Huygens (1629-1695) developed a wave theory to
explain light. A more prosaic discovery, and one that promised more immediate
practical results, demonstrated the material composition of air. The German
physicist, Otto von Guericke (1602-1668), pumped air from two joined steel
hemispheres, creating a vaccum so complete that the two sections could not be
pulled apart by teams of horses. Ultimately, Guericke and other scientists
proved that air could be weighed and that it could exert pressure, both
properties in accord with Newton's law.
Although electricity remained a challenging mystery to physicists during
this era, magnetic properties were recognized early. In 1600, the Englishman
William Gilbert (1540-1603) published a book that described magnetic force and
the possibilities of generating it by friction. Gilbert's suggestion of a
similarity between magnetism and gravity exerted some influence on Newton.
Electricity, generated by friction, was conducted short distances to produce
sound and light in various experiments during the seventeenth century. The
first crude storage battery - the Leyden Jar - was invented in 1745 at the
Dutch University of Leyden. A last important achievement during the period
came in 1752, when Benjamin Franklin (1706-1790), with his famous kite-and-key
experiment, proved that lightning is natural electricity.
While physics and astronomy flourished, chemistry advanced more slowly.
Robert Boyle (1627-1691), the son of an Irish nobleman and the father of
modern chemistry, was the first to emphasize the difference between compounds
(unified by chemical action) and mixtures. From his many experiments, he
conceived a crude atomic theory, superseding the "four elements" and "four
humors" of medieval alchemists and physicians. Boyle also investigated fire,
respiration, fermentation, evaporation, and the rusting of metals. Joseph
Priestley (1733-1804), an English dissenting minister and a famous
eighteenth-century chemist, isolated ammonia, discovered oxygen, and generated
carbon monoxide. Another Englishman, Henry Cavendish (1731-1810), discovered
hydrogen (1766). His experiments, along with Priestley's, furnished an
explanation for combustion.
More definitive studies of combustion were completed by the French
scientist Antoine Lavoisier (1743-1794), who is generally considered the
leading chemist of the eighteenth century. Lavoisier proved that burning is a
chemical process involving the uniting of oxygen with the substances consumed.
He also showed that respiration is another form of oxidation. Such discoveries
led him to define the law of conservation: "matter cannot be created or
destroyed." With this law, he laid a foundation for the discipline of
quantitative analysis, which makes possible the precise measurement of
substances in any compound. Much of the credit for Lavoisier's scientific
success should go to his wife, Marie-Anne (1758-1836), whom he married when
she was fourteen and educated in his laboratory. She assisted with all his
major experiments, took notes, kept records, illustrated his books, and
published her own papers. After he died on the guillotine during the French
Revolution, she edited and published a compilation of his works.
Robert Boyle's seventeenth-century counterpart in the life-sciences was
William Harvey (1578-1657). Born in England and educated at the University of
Padua in Italy, Harvey continued in the tradition that had earlier produced
Vesalius. Harvey's major contribution was a description of the human
circulatory system: He traced the flow of blood from the heart, through the
arteries, capillaries, and veins, and back to the heart. He also studied
embryology in animals and put forth the theory of "epigenesis," which
maintains that embryos develop progressively, through definite stages, prior
to birth. Harvey provided medical science with many practical keys to
understanding the human body. He also applied to biology the mechanistic
interpretation developed by Galileo, Newton, and other modern scientists.
Biologists in the seventeenth century also achieved notable results. Jan
Swammerdam (1637-1680) in Holland and Marcello Malpighi (1628-1694) in Italy
studied circulation and added details to Harvey's general description. Anton
van Leeuwenhoek (1627-1723), a Dutch biologist, discovered protozoa, bacteria,
and human spermatozoa; Swammerdam studied the anatomies and life cycles of
frogs and insects; and Robert Hooke (1635-1703), an Englishman, first
described the cellular structure of plants. These studies, as did those of
William Harvey, also furthered the idea of bodies as machines.
Biology in the eighteenth century was characterized by classification
rather than the formulation of theory. An early example was Maria Sibylla
Merian (1647-1717), a German entomologist who settled in Holland. She was a
specialist on insects, and in 1705 published a well-known treatise dealing
with those of Surinam, where she had studied for two years. Her work was just
one approach to thousands of new species, discovered as a result of overseas
expansion and collected in Europe, where they were classified and described.
The most successful classifiers were John Ray (1627-1705) in England, Karl von
Linne (1707-1778) - perhaps better known by his Latin name as Linnaeus - in
Sweden, and Georges Buffon (1707-1788) in France. They established the basic
terminology and categories still used in the twentieth century.
Three women deserve mention for their contributions to eighteenth-century
anatomy and medicine. A recognized expert in anatomy was Anna Manzolini
(1716-1774), professor at the University of Bologna, a lecturer at the Court
of Catherine the Great, and a member of the Russian Royal Scientific Society.
The French anatomist Genevieve d'Arionville (1720-1805), wrote treatises on
chemistry, medicine, anatomy, and physiology. In addition to her
self-illustrated textbooks on anatomy, she published a study on putrefaction
and introduced bichloride of mercury as an antiseptic. Mary Motley Montague
(1689-1762) was not a research scientist or a medical doctor, but she
advocated innoculation against smallpox in England, a treatment she had
observed in Turkey as the wife of the English ambassador there. Her efforts
aided the English physician Edward Jenner (1749-1823), who published his
famous defense of vaccination in 1798.
The most revolutionary thesis in modern biology, the evolutionary theory
that all life has evolved from simpler organisms, was not yet widely accepted
in the eighteenth century, although some classifiers, such as Buffon, were
already speculating along these lines. A stronger case was argued by the
Scottish gentleman farmer, James Hutton (1726-1797). In his Theory of the
Earth (1795), Hutton described the earth as constantly wearing away and
rebuilding itself through natural results of wind, water, and chemical
reactions. This thesis contradicted traditional religious theories of creation
and supported the concept of natural law.
Science As Popular Culture
The achievements of science, particularly its practical applications in
such fields as medicine and navigation, completely transformed its social
role. After long being suspect among the leaders of society, it now became
respectable. By the beginning of the eighteenth century, scientists frequented
the best salons, and scientific academies gained public support as they sprang
up all over Europe. The most famous were the Royal Society of London,
chartered in 1662, and the French Academy of Science, founded in 1664. Most
academies published journals that circulated widely. Scientists and would-be
scientists carried on voluminous correspondence, developing a cosmopolitan
community with its own language, values, and common beliefs.
Rising enthusiasm on the public fringes of the scientific community was
matched by a popular mania. Frederick the Great dabbled in scientific
experiments, as did hundreds of other ordinary craftsmen, wealthy merchants,
and bored nobles. Support for academies was merely one form of public
endorsement. Kings endowed observatories; cities founded museums; and
well-to-do women helped establish botanical gardens. Scientists became popular
heroes. Giordano Bruno, an Italian philosopher-scientist, had been burned for
heresy by the Holy Inquisition in 1600; Galileo was hounded by persecutors
through his most productive years; but Newton received a well-paying
government position. He was lionized and knighted during his lifetime, and
after he died in 1727, he was buried in a state funeral at Westminster Abbey.
By 1700, science had surpassed the Reformation in affecting Western
thought. Unlike the Reformation, science revolutionized people's view of their
own purposes. No longer could they consider the universe as stage equipment,
created by God expressly for the human drama of sin and salvation. People now
looked up toward an unknown number of stars, each moving silently but
regularly through infinite space. On one planet, orbiting one of the smaller
stars, were human creatures, among other forms of life. Their obvious
similarity was material composition, which also obeyed Newtonian principles.
Matter and motion, the fundamental realities of this strange new universe,
everywhere acted impersonally, without discernible human purpose. In all of
this, the individual was apparently rendered insignificant, but some thinkers
sensed more human potential than had been promised formerly by Christian free
will. For if God were not directly determining human affairs, human reason
might learn the natural laws and effect unlimited human progress.
