World History: Patterns of Interactions          Chapter 22, Section 1 (pages 544-550)


Note: Click on the terms in yellow for more information




544, 546-7

Galileo Galilei: Brilliant scientist and mathematician who was the first European to make systematic observations of the heavens by means of a telescope.  Such observations include the mountains on the moon, the phases of Venus, and the moons circling Venus. He published his findings in The Starry Messenger in 1610. Additionally, he further infuriated the Church by discovering the law of inertia, i.e., a body in motion continues in motion forever unless deflected by an external force. Galileoís discoveries, along with those of Kepler, firmly argued the reasonableness of Copernicusí heliocentric theory.  See Nicolaus Copernicus for further information.


heliocentric theory The idea that the earth and the other planets revolve around the sun.  This theory was first proposed by the Greek astronomer Aristarchus in the third century BC.  However, the geocentric theory, which was formulated by the Greek astronomer Ptolemy, was the accepted view for the next 14 centuries.



Isaac Newton: English scientist who discovered the law of gravity. He proved that the same force ruled the motions of the planets, the pendulum, and all matter on earth and in space. In doing so, he disproved the idea that one set of physical laws governed Earth and another set governed the rest of the universe. In 1687, he published his ideas in a work called Mathematical Principles of Natural Philosophy.


Johannes Kepler: Devised the three laws of planetary motion: the planets revolve around the sun in elliptical orbits, planets move more rapidly as their orbits approach the sun, and the time taken by planets to orbit the sun varies proportionately with their distance from the sun. Keplerís work proved the heliocentric theory.


Nicolaus Copernicus: Polish cleric and astronomer who proposed the heliocentric theory. Fearing persecution from scientists and clergy, he did not publish his book, On the Revolutions of the Heavenly Bodies, until 1543, the last year of his life. Opponents feared that the heliocentric theory would remove human beings from their special place in the universe (indeed, they believed that God had deliberately placed Earth at the center of the universe. Earth was thus a special place on which the great drama of life took place). Having far-reaching ramifications, his work helped stimulate the Scientific Revolution.


scientific method: A logical procedure for gathering information about the natural world, in which experimentation and observation are used to test hypotheses. Modern scientific methods are based on the ideas of Francis Bacon, an English politician and writer, and Rene Descartes, a French mathematician.


William Harvey: An English doctor who published On the Motion of the Heart and Blood in Animals, which showed that the heart acted as a pump to circulate blood throughout the body. He also described the function of blood vessels.