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Scientific Revolution & Enlightenment
In 1543 Nicolaus Copernicus put the Sun, not the Earth, at the centre of the universe. Over the next century and a half Galileo, Kepler and Newton replaced ancient authorities with observation, experiment and mathematics. In the 18th century the thinkers of the Enlightenment applied reason to society itself - to religion, government and the rights of the individual - and their ideas fed the American and French revolutions.
A new picture of the heavens
THEME ONE
Copernicus's Sun-centred system was at first a mathematical idea. Tycho Brahe measured the planets more precisely than anyone before him, and Johannes Kepler used his data to show that they move in ellipses. From 1609 Galileo Galilei turned a telescope to the sky and saw mountains on the Moon, the phases of Venus and four moons circling Jupiter - things that the old Earth-centred picture could not explain.
Experiment and Newton
THEME TWO
Francis Bacon called for knowledge built on experiment, René Descartes for knowledge built on doubt and reason. Scientific societies such as the Royal Society of London (1660) shared results in letters and journals. In 1687 Isaac Newton's Principia showed that one law of gravitation explains both a falling apple and the orbits of the planets. Nature, it seemed, followed rules that people could discover.
Reason and society
THEME THREE
If nature had laws, perhaps society did too. John Locke argued in 1689 that people have natural rights to life, liberty and property, and that government rests on their consent. Montesquieu proposed separating legislative, executive and judicial power. Voltaire fought for religious tolerance, Rousseau wrote of the general will of the people, and Diderot's Encyclopédie (1751 – 1772) gathered the knowledge of the age.
From ideas to revolutions
THEME FOUR
Some rulers - Frederick II of Prussia, Catherine II of Russia, Joseph II of Austria - adopted Enlightenment ideas to make their states more efficient, without giving up power. Others drew more radical conclusions. In 1776 the Declaration of Independence of the United States proclaimed that "all men are created equal", and in 1789 the French National Assembly adopted the Declaration of the Rights of Man and of the Citizen.
Periods
The new astronomy
1543 – 1633
From Copernicus and Vesalius to Kepler's laws and Galileo's telescope, ending with Galileo's trial before the Inquisition.
The age of Newton
1633 – 1715
Descartes, scientific academies in London and Paris, the microscope, Newton's Principia and Locke's political philosophy.
The Enlightenment
1715 – 1789
Voltaire, Montesquieu, Rousseau and Kant, the Encyclopédie, enlightened rulers, and the American and French declarations of rights.
Key dates
- 1543Copernicus publishes his Sun-centred system, Vesalius his anatomy.
- 1610Galileo reports what he has seen through the telescope.
- 1687Newton publishes the Principia.
- 1751The first volume of the Encyclopédie appears in Paris.
- 1776The US Declaration of Independence and Adam Smith's Wealth of Nations.
- 1789The Declaration of the Rights of Man and of the Citizen.
Questions and answers
Was Galileo condemned for saying that the Earth moves?
Yes. In 1633 the Roman Inquisition found him "vehemently suspected of heresy" for defending the Copernican system, forced him to recant and kept him under house arrest until his death in 1642. In 1992 Pope John Paul II formally acknowledged that the Church had been wrong.
What did the Enlightenment mean by reason?
That people should use their own understanding instead of relying on tradition and authority - "Dare to know!", as Immanuel Kant put it in 1784. In practice it meant religious tolerance, freedom of speech, the rule of law and the idea that governments draw their legitimacy from the people.