17th Century, Century of Genius

®   In the early 1500’s those who probed into the secrets of nature did so in the dark, isolated from one another and from the general public, working often times by trial and error, not all together clear on what they were trying to do.

®   By 1727 when Newton died scientific men were in continual touch with each other and the scientific method had been defined.

Michel de Montaigne 1533-1592 “What do I know”

®  During this time there had developed a great deal of skepticism, a constantly doubting frame of mind, which held that no certain knowledge is possible for human beings at all, that all beliefs are essentially only customs, that some people believe one thing and others another and there is no sound way of choosing between them.

Scientific View of the World

Prophets of a scientific civilization:

Rene Descartes

and Sir Francis Bacon

Bacon and descartes

®   Both asked how it was possible for human beings to know anything with certainty

®   Both branded all beliefs of the preceding generations (outside of religion) as worthless

®   Both rejected the methods of the scholastics

®   Both saw truth as something that is we find at the end after a long process of experiment and investigation

®   Both maintained that there was a true and reliable method of knowledge

Sir Francis Bacon 1561-1626

®   Novum Organum 1620

®   Inductive Reasoning

®   Empiricism

®   Not a pure Scientist

®   Failed to grasp importance of Math

Francis Bacon

®   1620 published Novum Organum or new method of acquiring knowledge.

®   He insisted on the use of the inductive method- where one discovers truth by moving from the particular to the general, the concrete to the abstract

®   Look at the world with fresh eyes, observe and study all things that are perceived by the senses.

Bacon, cont.  Empiricism

®  Bacon became a leading philosopher of empiricism

®  The founding of knowledge on observation and experience

Bacons weakness

®  Failure to understand the role of mathematics in science.

®  Math often uses deductive reasoning-dealing with abstractions and proceeding from axioms to theorems-was not an inductive or empirical method as demanded by Bacon

Rene Descartes 1596-1650

®   Discourse on Method 1637

®   Systematic Doubt

®   Cogito ergo sum

®   Cartesian dualism

®   Thinking substance

®   Extended substance

 

Rene Descartes

®   Considered the inventor of coordinate geometry

®   Believed that the vast world of nature could be reduced to mathematical form.

®   In his Discourse on Method 1637 Descartes advanced the principle of systematic doubt

®   Cogito ergo sum “ I think therefore I am”

®   Cartesian Dualism

®   Two realities Thinking substance (deductive) and Extended substance (Inductive)

Development of Astronomy as Science

®   Aristotle 384-322 BC

®   Aristarchus of Samos 200 BC

®   Ptolemy 150 AD

®   Copernicus 1473-1543

®   Tycho Brahe 1546-1601

®   Johannes Kepler 1571-1630

®   Galileo 1564-1642

®   Isaac Newton 1642-1727

Aristotle

®   Earth was seen as imperfect and situated at the center of the Universe (Geocentric)

®   Composed of 4 elements earth, water, air, fire

Aristotle, cont.

®  Planets move in circular motion

®  Aristotles views were “Christianized” by the 13th century, it became the basis for University on the subject.

Ptolemy- Geocentric

®   Earth; immovable at the center of the universe

®   Order; earth, moon, Mercury, venus, sun, Mars, Jupiter, Saturn

®   Enclosed by sphere of fixed stars

®   Planetary spheres moved with the aid of God.

Ptolemaic system

Copernicus

®   Heliocentric

®   “On the revolutions of Heavenly Orbs (Spheres)”

®   Book published at the end of his life

®   Questioned Ptolemaic system for its math

®    Heliocentric easier to explain than geocentric

®   Accepted circular orbits

Copernican System

Tycho Brahe -Danish

®   Provided most accurate DATA with regard to planetary location

®   Had Johannes Kepler as his apprentice

Johannes Kepler

®   Showed that Copernicus, Ptolemy and Aristotle’s view of circular orbits did not match data

®   Discovered elliptical orbit. No epicycles.

Kepler’s elliptical orbit

Galileo

®   Planets had been thought of as orbs

®   Galileo’s telescope

®   Moon was rough, mountainous, not a luminous object

®   Jupiter had moons (satellites)

 

Galileo

®  Where Kepler had found mathematical laws describing the movement of planets, Galileo found laws describing the movement of bodies on earth.

®  Leaning Tower of Pisa

Isaac Newton

®   Synthesized Kepler and Galileo

®   Universal law of Gravitation

®   “Principia”

®   Developed Calculus

 

Societal Impact

®  Man was no longer the center of creation

®  The old cosmos comfortably enclosed and ranked in ascending order of purity, gave way to a cosmos that seemed to consist of an infinite emptiness.