Scientific Revolution

Chapter 22 Section 1

Ancient & Medieval Science• Aristotle’s Geocentric

Theory – earth was center of the universe– Sun, moon, planets moved

around earth in circular paths• Greek astronomer Ptolemy

supported the geocentric theory

• Medieval Christianity taught that God had placed earth in center of the universe

Scientific Revolution = new way of thinking about natural world

• Careful observation, questioning accepted beliefs

Causes of the Scientific Revolution

• Middle Ages establishment of universities• Renaissance encouraged scientific progress• Reformation led people to question, printing press• Exploration need for navigational technologies

Nicolaus Copernicus (1473-1543)• Polish cleric & astronomer

• Heliocentric Theory: sun was center of universe

• Feared persecution, so did not publish findings until his death

• Wrote On the Revolutions of the Heavenly Bodies

Tycho Brahe (1546-1601)• Danish astronomer• Built sophisticated

observatory• Collected numerous data to

support heliocentric theory• Star catalogue

Johannes Kepler (1571-1630)

• Brahe’s assistant

• Mathematical laws governed planetary motion

• Elliptical orbits around sun, not circles

Galileo Galilei (1564-1642)• Italian scientist

• Built own telescope

• Discovered Jupiter’s four moons, Saturn’s rings, sun spots, rough surface of moon– Published Starry

Messenger

• Summoned to stand trial before the Inquisition

Scientific Method: logical procedure for gathering & testing ideas

• Question, hypothesis, experiment, observe, record data, conclude

• Francis Bacon

- English statesman & writer

- Empiricism (experimental method) experiment & then draw conclusions

- Generate practical knowledge to improve people’s lives

Scientific Method • René Descartes

- Developed analytical geometry

- Doubt until proven by reason

- Mind and matter “I think, therefore I am”

- Observation, experimentation, general mathematical laws led to understanding of world

Isaac Newton (1642-1727)• Law of universal gravitation

every body in universe attracts every other body

• Mathematical relationships degree of attraction depends on mass & distance

• Published The Mathematical Principles of Natural Philosophy in 1687

• Universe was giant clock; God was clockmaker

Scientific Instruments• Zacharias Janssen first microscope• Anton van Leeuwenhoek used

microscope to discover bacteria & red blood cells

• Gabriel Fahrenheit & Anders Celsius thermometers for temperature

Leeuwenhoek & his

microscope

Advances in Medicine• Andreas Vesalius studied anatomy & muscle

contraction

• William Harvey described circulatory system & heart

• Edward Jenner introduced smallpox vaccine

Discoveries in Chemistry

• Robert Boyle founder of modern Chemistry

- The Sceptical Chemist (1661)

- challenged Aristotle’s ideas of four elements

- Boyle’s law explains how volume, temperature, and pressure of gas affect each other

Results of the Scientific Revolution• Rise of new social group international scientific

community

• Introduced new knowledge about nature & revolutionary way of obtaining such knowledge

• Scientific point of view begins to dominate European thought, people of 1700’s spoke of their changing times as an “Age of Enlightenment.”