Download Science and Enlightenment

Science and Enlightenment
Theme: The changes in scientific thought,
religion, social order, and attitudes toward
government wrought by the Scientific
Revolution and the Enlightenment
Lesson 4
Agenda
• Science
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Copernicus
Kepler
Galileo
Newton
• Enlightenment
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Philosophes
Voltaire
Montesquieu
Smith
Locke
Science
Ptolemaic Universe
Galileo
New Ideas
• During the Middle Ages, scientific ideas were largely
based on religious traditions rather than direct
observation and mathematical reasoning
• During the 17th and 18th Centuries, scholars began
relying on observation and mathematics to transform the
natural sciences
– The “scientific revolution”
• The result impacted well beyond the scientific
community, affecting moral, social, and political thought
• The change weakened the influence of churches and
encouraged the development of secular thinking
The Ptolemaic Universe
• 2nd Century A.D.
Greek scholar
Claudius Ptolemy
envisioned a
motionless earth
surrounded by a
series of nine
hollow, concentric
shapes that
revolved around it
The Ptolemaic Universe
• Ptolemy’s first seven spheres
held the moon, Mercury,
Venus, the sun, Mars, Jupiter,
and Saturn
• The eighth sphere held stars
• The ninth sphere was empty,
surrounded the whole cosmos,
and provided the spin that kept
the other spheres moving
• Beyond the spheres, Christian
astronomers placed Heaven
Claudius Ptolemy
The Ptolemaic Universe
• Heavenly bodies were thought to be
composed of a pure substance that
did not experience change or
corruption
• They were not subject to the physical
laws that governed the Earth
• Each made a perfect circular path in
revolving around the Earth
The Ptolemaic Universe
• This cosmology did not account
for observations of erratic
movements on the part of the
planets
• These were explained by an
elaborate and difficult system of
adjustments known as epicycles
• As astronomers gathered more
data on planetary movements,
they sought to reconcile their
observations with Ptolemaic
theory by adding more
epicenters
The eccentric, epicycle and
equant combined. The
planet (P) revolves around
the center of the epicycle
(D) which moves around the
center of circle (C) but
moves uniformly around the
center of motion (M). The
earth (E) is not at the center
of motion or the center of
the eccentric.
Nicolaus Copernicus
• In 1543,Copernicus
published On the
Revolutions of the
Heavenly Spheres
which argued that the
sun, rather than the
Earth, stood at the
center of the universe
and that the planets
revolved around the
sun
Nicolaus Copernicus
• Copernicus’ idea harmonized much better
with observed data than did Ptolemy’s, but
it was not warmly received
• If Copernicus was right, then the Earth
was just another planet and human beings
were not the center of the universe
• At the time, this had serious religious
ramifications
Impact beyond Science
• “Of all discoveries and opinions, none may have exerted a
greater effect on the human spirit than the doctrine of
Copernicus. The world had scarcely become known as
round and complete in itself when it was asked to waive
the tremendous privilege of being the center of the
universe. Never, perhaps, was a greater demand made
on mankind - for by this admission so many things
vanished in mist and smoke! What became of our Eden,
our world of innocence, piety and poetry; the testimony of
the senses; the conviction of a poetic - religious faith? No
wonder his contemporaries did not wish to let all this go
and offered every possible resistance to a doctrine which
in its converts authorized and demanded a freedom of
view and greatness of thought so far unknown, indeed not
even dreamed of.”
– Johann Wolfgang von Goethe
Scientific Revolution
• Copernicus’ work inspired astronomers to
examine the heavens in new ways
• Increasingly they based their theories on
observed data and used mathematical
reasoning to organize the data
• Gradually Copernicus’ model replaced Ptolemy’s
• This reliance on observation and mathematics
ushered in the “Scientific Revolution”
Johannes Kepler (1571-1630)
• Johannes Kepler
used mathematics to
demonstrate that
planetary orbits are
elliptical, not circular
as in the Ptolemaic
theory
Kepler’s First Law
• The orbits of the planets are ellipses, with the sun
at one focus of the ellipse.
Kepler’s Second Law
• The line joining the planet to the sun sweeps
out equal areas in equal times as the planet
travels around the ellipse.
Kepler’s Third Law
• The ratio of the squares of the revolutionary
periods for two planets is equal to the ratio of
the cubes of their semimajor axes:
Kepler’s Third Law
Object
a (AU)
P (year)
a**3
P**2
Mercury
0.387
0.241
0.058
0.058
Venus
0.723
0.615
0.378
0.378
Earth
1.00
1.00
1.00
1.00
Mars
1.52
1.88
3.51
3.53
Jupiter
5.20
11.9
141.
142.
Saturn
9.54
29.5
868.
870.
Uranus
19.2
84.0
7,080.
7,060.
Neptune
30.1
165.
27,300.
27,200.
Pluto
39.5
248.
61,600.
61,500.
Galileo Galilei (1564-1642)
• Galileo used the
telescope to observe
spots on the sun and
moon
– Discredited the
Ptolemaic notion that
the heavenly bodies
are smooth,
immaculate,
unchanging and
perfectly spherical
Galileo’s drawing of the
moon showing craters
Galileo Galilei
• Other achievements:
– Noticed four of the moons
that orbit Jupiter
– Observed previously
unknown distant stars
– Meant universe is much
larger than previously
suspected
– Showed that the velocity of
falling bodies depends not
on their weight but on the
height from which they fall
Galileo’s telescope
Galileo Galilei
• In 1632, he published
his Dialogue
Concerning the Two
Chief World Systems
which compares the
Copernican and
Ptolemaic systems
– Found guilty of heresy
by the Spanish
Inquisition and spent
the rest of his life
under house arrest
Galileo’s Dialogue
Isaac Newton (1642-1727)
• Newton used observation and
mathematical reasoning to
synthesize astronomy and
mechanics (the branch of
physics that deals with the
motion of bodies)
• Culminating figure of the
Scientific Revolution
– “If I have been able to see
further, it was only
because I stood on the
shoulders of giants.”
Isaac Newton
• Wrote the Mathematical Principles of Natural Philosophy
in 1687
• United the heavens and Earth in a vast, cosmic system
• A law of universal gravitation regulates the motion of
bodies throughout the universe
• Newton’s laws allowed him to explain seemingly
unrelated phenomena using gravitation
– The ebb and flow of the tides and the gravitational
pull of the moon
– The eccentric orbits of planets and comets and the
gravitational influence of the sun, the Earth, and other
heavenly bodies
Isaac Newton
• Newton put Galileo’s observations about the relations
between the forces acting on a body and the motion
of the body into useable form
• Three laws of motion:
– An object at rest tends to remain at rest and an
object in motion tends to remain in motion unless
acted upon by an outside force. (inertia)
– The speed and direction in which an object moves
depends on the mass of the object and the
amount of force that is applied to it and the
direction of the force. (F=ma)
– For every action, there is an equal and opposite
reaction.
Tides
• Gravity and inertia are opposing forces acting on the Earth’s
oceans, creating tidal bulges on opposite sides of the planet.
• On the “near” side of the Earth (the side facing the moon), the
gravitational force of the moon pulls the ocean’s waters toward it,
creating one bulge.
• On the far side of the Earth, inertial forces dominate, creating a
second bulge.
Enlightenment
Abbé Delille recites a
poem in the salon of
Madame Geoffrin, site of
many gatherings of the
Enlightenment
philosophes
Impact of the Scientific Revolution
• Suggested that rational analysis of behavior and
institutions could have meaning in the human as
well as the natural world
• Increasingly, thinkers challenged recognized
authorities such as Aristotelian philosophy and
Christian religion and sought to explain the world
in purely rational terms
• The result was a movement known as the
“Enlightenment”
Philosophes
• Enlightenment thinkers sought to discover
natural laws that governed human society
in the same way Newton’s laws regulated
the universe
• Collectively, these thinkers were called the
philosophes (“philosophers”)
Absolutism
• King Louis XIV (1643-1715) of France is credited with
having said “L’etat c’est moi!” or “I am the state.”
• Louis’ statement is consistent with the idea of
absolutism– the theory that ultimate power in the early
centuries of modern Europe was vested in a hereditary
monarch who claimed a God-given right to rule
• Louis went so far as to call himself the “Sun King,”
claiming that like the sun, everything revolved around
him
• Catholicism was the national religion of France
– “One faith, one law, one king.”
– In 1685 Louis revoked the Edict of Nantes and insisted that
Huguenots convert to Catholicism
Philosophes
• Believed that natural science would lead to
greater human control over the world
and
• Rational science of human affairs would lead to
individual freedom and the construction of a
prosperous, just, and equitable society
• Their central ideas included
– Progress
– Deism
– Tolerance
Central Ideas of the Philosophe
Movement: Progress
• Most philosophes were optimistic about the
future because they believed in the inevitability
of progress
• Saw human history largely as a history of the
improvement of humanity in three respects:
– Developing a rational knowledge of the natural world
and the ability to manipulate the world through
technology
– Overcoming ignorance bred of superstitions and
religions
– Overcoming human cruelty and violence through
social improvements and government structures
Central Ideas of the Philosophe
Movement: Deism
• Not all, but most philosophes, were Deists
– Believed in the existence of a god, but denied
the supernatural teachings of Christianity
such as Jesus’ virgin birth, miracles, and the
resurrection
– Deists believed in a powerful god who set the
universe in motion and established natural
laws to govern it, but then took no personal
interest in the universe and did not intervene
in its affairs (“The Watchmaker”)
Central Ideas of the Philosophe
Movement: Deism
• Deists believe
– Religion should be reasonable and should
result in the highest moral behavior of its
adherents
and
– The knowledge of the natural world and the
human world has nothing to do whatsoever
with religion and should be approached
completely free from religious ideas or
convictions.
Thomas Paine (1737-1809)
on Deism
• “Here it is that the religion
of Deism is superior to
the Christian Religion. It
is free from all those
invented and torturing
articles that shock our
reason or injure our
humanity, and with which
the Christian religion
abounds. Its creed is
pure, and sublimely
simple. It believes in
God, and there it rests.”
Central Ideas of the Philosophe
Movement: Tolerance
• The philosophes
hated the crimes
they felt had been
perpetrated in the
name of religion and
the name of God
• They felt a fair, just,
and productive
society absolutely
depended on
religious tolerance
Torture during the Spanish Inquisition
Francis-Marie Arouet (1694-1778)
(Voltaire)
• Was especially critical of the
Roman Catholic Church which he
held responsible for fanaticism,
intolerance, and incalculable
human suffering
• Wrote Candide in 1759 in which
he analyzes the problem of evil in
the world and depicts the woes
heaped upon the world in the
name of religion
• His battle cry against the Roman
Catholic Church was ecrasez
l’infame (“crush the damned
thing”)
Baron de Montesquieu (1689-1755)
• Sought to establish a
science of politics and
discover principles that
would foster political
liberty in a prosperous
and stable state
• Instrumental in
developing the idea of
separation of powers
(executive, legislative,
judicial)
John Locke (1632-1704)
• Studied the relationship
between the individual
and the state
• Wrote An Essay
Concerning Human
Understanding in 1689
• Largely anti-authoritarian
– Opposition is both on
the level of the
individual person and
on the level of
institutions such as
government and
church
John Locke
• Individuals should use reason to search after truth rather
than simply accepting the opinion of authorities or being
subject to superstition
– Proportion assent to propositions to the evidence for
them
• There must be a distinction between the legitimate and
illegitimate functions of institutions
– Based on those distinctions, there is a corresponding
distinction for the uses of force by those institutions.
• By using reason to try to grasp the truth and by
determining the legitimate functions of institutions, the
individual and society will flourish materially and
spiritually
John Locke
• Thomas Hobbes (1588-1679) had described a
social contract in which people in a state of
nature ceded their individual rights to a strong
sovereign in return for his protection
• Locke offered a new social contract theory in
which people contracted with one another for a
particular kind of government, and that they
could modify or even abolish the government
– Great influence on Thomas Jefferson and the
Declaration of Independence
Adam Smith (1723-1790)
• Focused on
economics and held
that laws of supply
and demand
determine what
happens in the
marketplace
• Wrote An Inquiry into
the Nature and
Causes of the Wealth
of Nations in 1776
which argued the
virtues of a free
market economy
Adam Smith
• Free enterprise system
• The role of self-interest and laissezfaire
– Through an “invisible hand” self-interest
guides the most efficient use of
resources in a nation’s economy, with
public welfare coming as a by-product
– State and personal efforts to promote
social good are ineffectual compared to
unbridled market forces
• Provides the intellectual rationale for
free trade and capitalism
– (We’ll discuss capitalism in Lsn 8)
Change Wrought by Enlightenment
• Weakened the influence of organized
religion, but certainly did not destroy
institutional churches
• Encouraged the replacement of Christian
values (which had guided European
thought on religious and moral affairs for
over a thousand years) with a new set of
secular values
Legacy of the Enlightenment
• Debate on whether evolution or
creationism should be taught in schools
• Debate on Judeo-Christian values and
secular humanism
• Debate on free trade and protective tariffs
• Debate on what the role and authority of
government should be
Next
• Atlantic Slave Trade