The Scientific Revolution: Causes and Consequences

1. The Scientific Revolution: Causes and Consequences Unit 3 - Day 2

2. Ways of Knowing - Recap Ways of Knowing (epistemology) Authority Reason General Principle or Law Deduction Induction DEDUCTION INDUCTION Individual Examples

3. The Problem with the Scientific Method • Because the Scientific Method relies mainly on INDUCTIVE REASONING, conclusions reached using this method can never be absolutely certain. • We have become ok with this – in fact we either ignore it, or if we are aware of it, we call this “flexibility” • It takes people a long time to become “ok” with this • AUTHORITY and DEDUCTIVE REASONING produce absolute certainty

4. The Scientific Revolution – Two Fundamental Changes • The Scientific Revolution was about more than just finding the “right” answers to questions. • Much more importantly the Scientific Revolution was about two fundamental but interrelated changes in the way people understood the world. • Change in how people KNOW (epistemology). • Authority vs. Reason • People gradually become less satisfied with existing sources of “truth” – Aristotle, Bible • Reason - Deduction vs. Induction • People gradually become more comfortable with the uncertainty inherent in inductive reasoning • Change in how people SEE. • Scientists begin to observe the world more closely • Later scientists begin to experiment on the world

5. A Funny Story about Seeing and Knowing One day I was at the home of a very famous doctor in Venice, where many persons came … to see an anatomical dissection performed by a man. … He was investigating the source and origin of the nerves about which there exists a notorious controversy [in ancient Greek medical texts. Aristotle and Galen (a famous medical writer) believed nerves began in the heart]. The anatomist showed that the … nerves, leaving the brain … extended down the spine and … only a single strand… arrived at the heart. Turning to a gentleman whom he knew to be an [Aristotelian] philosopher … he asked this man whether he was … satisfied that the nerves originated in the brain and not the heart. The philosopher after considering this for a while, answered “You have made me see this matter so plainly and clearly that if Aristotle’s text were not contrary to it, stating clearly that nerves originate in the heart, I should be forced to admit it to be true.” - Galileo, Dialogue Concerning the Two Chief World Systems (1632)

6. Two Smart Guys – Aristotle and Galen Aristotle – Greek Philosopher (384-322 BCE) Galen – Roman Doctor (129-200 CE)

7. The Body in the Middle Ages The way the body looked to medieval people – page from medieval medical textbook. The text around the picture is from Galen.

8. The Problem of Observation

9. The Body in the Middle Ages A medieval anatomy lesson with dissection.

10. The Body in the Scientific Revolution • A New Doctor – A New Body • Andreas Vesalius (1514-1564) • Dutch-born Physician • Taught medicine at University of Padua (Italy) • 1543 –Publishes new textbook on anatomy, On the Workings of the Human Body • Same year Copernicus publishes On the Revolutions of the Heavenly Spheres • Textbook attacks many of the established theories of Aristotle and Galen on the basis of Vesalius’s own dissections. • Book is illustrated with detailed printed images.

11. The Body in the Scientific Revolution An anatomy lesson from the title page of Vesalius’s book.

12. The Body in the Scientific Revolution

13. The Body in the Scientific Revolution From Observation to Experimentation William Harvey’s experiments to demonstrate the circulation of blood (1628). This illustrates an experiment to show that blood in the veins only flows toward the heart because of valves that stop blood from flowing back away from it.

14. Seeing in the Scientific Revolution • In the scientific revolution, people began to SEE the world differently. • Begin to make careful observations of the world. • Empiricism – school of thought that stresses the importance of observable evidence • This is an important step in making people comfortable with inductive reasoning General Principle or Law INDUCTION Empirical Observation Individual Examples

15. Seeing in the Scientific Revolution Instruments develop to help people SEE the world better and more precisely. Galileo’s Telescope Tycho Brahe’s Observatory

16. Seeing in the Scientific Revolution Robert Hooke’s Microscope (1670)

17. Showing in the Scientific Revolution The power of the PRINTING PRESS to break down established AUTHORITYlies only partially in the speed of reproduction. If you want to give people faith in the value of INDUCTIVE REASONING you have to make them SEE WHAT YOU SEE. Hooke – Images of Cork Plant Harvey – Images of Circulation Galileo – Images of Moon