INTRODUCTION: During the Middle Ages “natural philosophers” as medieval scientists were known, did not make observations of the natural world. They relied on a few ancient authorities – especially Aristotle – for their scientific knowledge. A number of changes in the 15 th and 16 th centuries caused them to abandon their old views and develop new ones.

THE BIG QUESTION: How did the Scientific Revolution change people’s view of the natural world?

NEW DEVELOPMENTS Newly discovered Greek works by Ptolemy, Archimedes, and Plato The printing press helped spread new ideas The invention of the telescope, microscope, and other measuring instruments New developments in mathematic

Two Types of Scientific Thinking Inductive reasoning: Proceeding from the particular to the general Ex. Every time I eat oranges I get sick, therefore I get sick because I eat oranges. Deductive reasoning: Working from the general toward the specific Ex. All oranges are fruits fruit grows on trees, therefore all oranges grow on trees

A New Scientific Philosophy Rationalism: The belief that reason is the chief source of knowledge

ROOTS OF SCIENTIFIC REVOLUTION can be found in the Renaissance with the works of Copernicus, Galileo and other scientists Rejected traditional authority and church teachings in favor or direct observation of nature Scientific method – people observed nature, made hypotheses about relationships, and then tested through experiments.

OPPOSING THEORIES This system places the Earth at the center of the universe. The Earth is fixed at the center of concentric spheres, one inside the other, in which the heavenly bodies rotate around the earth. GEOCENTRIC THEORY (Ptolemaic)

HELIOCENTRIC THEORY (COPERNICAN) – This theory places the sun (not the earth) at the center of the universe, with planets revolving around the sun. The moon, however, revolves around the earth, and the earth rotates on its axis.

Galileo Galilei Italian astronomer Widely used telescopes and conducted tests on the motion of objects to find general principles of physics His idea was that the planets were composed of material substance Wrote “The Starry Messenger”

Nicholas Copernicus Polish astronomer Idea was that the sun was the center of the universe, and the moon revolved around earth Wrote “On the Revolutions of the Heavenly Spheres”

Johannes Kepler German astronomer, scientist, and mathematician Idea was that the orbits of planets were not circular, but elliptical Was able to prove this mathematically

Sir Isaac Newton English scientist and mathematician, and the most influential thinker of the Scientific Revolution laws of gravity and motion Wrote “Principia Mathematica” (connected the speed of falling objects on Earth to the movement of planets. Led to hope that the universe acted according to certain fixed and fundamental laws

William Harvey Scientist and physician He wrote a book called “On the motion of the Heart and Blood” published in He showed that the heart was the beginning point in the circulatory system, not the liver. He discovered that the same blood flows in both veins and arteries, and most important, that blood makes a complete circuit as it passes through the body.

Robert Boyle ( ) Irish Chemist (sometimes knows as the “Father of Chemistry) Conducted controlled experiments on gases at different temperatures and pressures. Pioneered work on the properties of gasses, which led to Boyle’s law. The law states that the volume of a gas varies with the pressure exerted on it. Distinguished mixtures from compounds

Francis Bacon English philosopher Invented the scientific method He wanted science to benefit industry, agriculture, and trade. He was more concerned with practical matters than pure science.