Ben Franklin and Electricity



Harvey and Blood Circulation

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




     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



     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.


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