The History of Observation a look at the role of observation and experimentation in science

The Greeks PLATO ( BC) reality is abstract “ideal forms”, vs. “shadows” that are physically observed –role of observation is deductive: leading away from big ideas to see how the details work out in the real world –knowledge is tested by argument and logic (not experimentation) ARISTOTLE ARISTOTLE ( BC) reality is the observed physical world, ideal forms are only useful constructs –role of observation becomes somewhat inductive: leading from observations towards patterns & big ideas –work is still mostly deductive

Scholastics (A.D. 1200’s) This group appeared after Greek and Arab knowledge had reached the West and been collected and shared. knowledge is based on accepted authority, not observations / experiments The first accepted authorities were scriptures, then also rediscovered Greeks, especially Aristotle knowledge is tested by argument and logic (look up the “trivium” of medieval universities!)

Empiricists Early Empiricists like Roger Bacon were “fringe” thinkers: later “Revolutionaries” like Descartes brought empiricism to the mainstream. ROGER BACON (c. AD ) backlash against scholastics (some the book facts were wrong!) experience is superior to argument experimental science as a valid route to truth: observation is key FRANCIS BACON (AD ) RENE DESCARTES ( ) extreme empiricism: science should be purely inductive science proceeds as we build up facts into proven theories quality obs. are facts unbiased by prior knowledge (idea of “objectivity”) “Cogito ergo sum” and interest in reduction of big ideas to mathematical principles

Constructivists (20th C.) KARL POPPER ( ) observations are context-bound & theory-driven: they will always depend on what the observer already knows role of observation is to test theories (ideas) science proceeds when –theories are proven false and we have to reconstruct what we know (revolutionary science) –we reaffirm, extend and apply useful theories (normal science) theories are created “constructs”, not absolute truth induced from observation

Matching Quotes Are these likely to have been written by a Greek, an Empiricist, or a Contructivist? “I frame no hypotheses; for whatever is not deduced from the phenomena is to be called a hypothesis; and hypotheses, whether metaphysical or physical, whether occult qualities or mechanical, have no place in experimental philosophy.” “Reason is immortal, all else is mortal.” Newton Principia 1687 Pythagoras c. 550 BC