Transcript Document
The Scientific Method 2/18/1996 …lots and lots and lots of math. Goal • • • • • What is the scientific method? What does the scientific method assume? Does the scientific method work? What is not a scientific argument. Does astrology follow the scientific method? The Scientific Method 1. Observe an event. 2. Develop a model (or hypothesis) which makes a prediction. model 3. Test the prediction. 4. Observe the result. 5. Revise the hypothesis. test 6. Repeat as needed. 7. A successful hypothesis becomes a Scientific Theory. Medical Science Scientific Method High Cholesterol Observation Patient has high cholesterol Hypothesis (prediction) Test Revise Certain chemicals may dissolve cholesterol deposits. Give 100 patients these give 100 patients placebo. Same number lower their as placebo patients. Try different combo of chemicals. New test? Re-run medical test. Observe Scientific Theory Lipitor reduces cholesterol. Observe result Everyday Science Scientific Method Car Repair Observation Engine won’t turn over. Hypothesis (prediction) Predict battery is dead. Test Replace battery. Observe result Engine now turns over. Revise hypothesis? Not needed. New test? Not needed. Scientific Theory Cars won’t work without a fully charged battery. Everyday Science Scientific Method Making Spaghetti Sauce Observation Spaghetti sauce should be red. Hypothesis Try a tomato sauce. Test Heat pot of tomato sauce. Observe result Taste the sauce - bland. Revise hypothesis? Use tomato sauce and garlic! New test? Add garlic, taste - not so bland. Scientific Theory The Final Recipe. Food Science • Throwing something together Hypothesis • Your grandmother’s time-tested recipe Scientific Theory. Repeatability • A successful theory is repeatable. – By you. – By anyone. • Examples: – Cold Fusion (1989) – Ecstasy (Science, 2003) Requirements • Objective reality – We all see the same world. • Constant Laws of Nature – What happens here, happens there. – What happened yesterday will happen tomorrow. • The Cosmos is knowable. Does it work? • Scientific Method is a tool. • Does this tool work? – Life expectancy – Mortality rates • Are there better tools? Theories • So: a theory is a highly successful hypothesis. • All hypotheses make predictions. • All theories make predictions. • All theories can be tested. • Result: Any scientific theory is subject to change as our ability to make tests, or make observations of a test’s results, improves with time. Non-scientific Theories • • • Make no predictions Un-testable Can’t be falsified Non-scientific Theories • Car won’t work? Aliens drained the battery. • Spaghetti is bland? You were meant to eat bland food. • Car won’t work? Gods must be angry. • Spaghetti is bland? At the instant of tasting, tongue is transported to alternate dimension where all flavors are rendered nullified. Happens instantaneously. Non-scientific Theories • The chain of events needed for life to arise is too complicated to have happened by chance, a divine intelligence must therefore have caused life to arise (Intelligent Design). • Face on Mars. Viking Orbiter (1976) Mars Global Surveyor (1998) Falsification • A real Scientific Theory tells you what observations are necessary to falsify it. – Not so proponents of: • • • • Face on Mars Moon Hoax Intelligent Design Astrologers Astrology Tests • What test would falsify astrology? Astrology and the President (TIME, May 16, 1988) -- Chief of Staff, Donald] Regan and “[Former White House “The First Lady dabbled in astrology others make a compelling case thatas infar 1986 and 1987 back as 1967. In 1981 [Joan] Quigleyreduced made the astrological influence dramatically Nancy a believer …. And from then on, no presidency's effectiveness, at least partly, by keeping presidential public appearance was slated Ronald under wraps without Reagan the Friend's say-so. Tofor thismuch day, of the time. Nancy's in the to scheduling process, Regan said Nancy's intrusions Friend continues influence the schedule. For thelast ReaganinPresident's an interview with TIME week, ‘began to interfere Gorbachev Washington cast with the normal conductsummit, of the she presidency.’” the charts of both men and determined that 2 p.m. on Dec. 8, 1987, was the most propitious moment (TIME, 16,the1988) for themMay to sign intermediate-range nuclear forces treaty. At Nancy's behest, the entire summit was built around that hour. For the upcoming Moscow summit, Gorbachev's chart (he is a Pisces) has been recast alongside Reagan's (Aquarius).” HW#3 • Devise a scientific test for some pseudoscience (astrology, tarot, etc). – What claim are you testing? – How will you test it? • Due Tuesday 16th.