Philosophy of the Sciences

1. Philosophy of the Sciences Early-Modern Scientific Method(s)

2. Modern Scientific Method • What is it today? What do we call it? • What is its purpose? • Which fields of study employ it? • Who are some important modern theoreticians of scientific method?

3. Ancient scientific method • Plato: visible vs intelligible realms; the sensible world is but a mere reflection of the real world of the Forms, • Mathematics provided Plato with his primary examples: geometry or the supposedly indivisible number one; • Plato’s idea of a real world known only to the intellect, standing behind our sensible world, has deeply influenced natural science (e.g particle & wave theories of light).

4. Ancient scientific method • Aristotle (a student of Plato) developed the beginnings of method in his Posterior Analytics; • He retained the idea of Forms in his notion of essence, but his method focused on the sensible objects themselves; • For instance, an investigator might examine a variety of mammals, concluding that the essence of being a mammal is being gestated inside the mother and nursed on milk.

5. Ancient scientific method -Few experiments, although Aristotle’s student Theophrastus did plant seeds sent to Athens by Alexander the Great; -Little practical interest, except in the later Hellenistic and Roman periods (especially in medicine); -Most activity we would now deem ‘scientific’ was observational in character, e.g. Aristotle’s treatises on animals; -Astronomy, highly developed already by the Babylonians, originated in religion.

6. Medieval Scientific Method • Followed Aristotle, ‘The Philosopher’, treating his writings as the guide to method; • Most treatments highly theoretical, focused on discussions of ‘resolution’ and ‘composition’ (aka ‘analysis’ and ‘synthesis’); • Roger Bacon (14th cent.) suggested the outline of modern method: checking new consequences deduced from first principles.

7. Early-Modern Scientific Fields • Natural History: Botany, Zoology • Medicine • Anatomy • Astronomy • Mathematics • Mechanics/Physics • Mineralogy

8. Theoreticians of Method • Galileo • Bacon • Descartes • Boyle • Newton • Locke

9. Sir Francis Bacon • Attacked Aristotle for premature theorizing from too few cases; • Claimed A., even when he performed experiments, allowed preconceived notions (‘idols’) and logic too great a role in his conclusions; • Proclaimed ‘induction’ to be the key to overcoming Aristotelian deficiencies in scientific method: ‘First we must compile a good, adequate natural and experimental history. That is the foundation of the matter’ (NO II, x).

10. Bacon, cont. • Induction—definition? • Is it the only game in town? (Deduction? Retroduction?) • No: what else does Bacon suggest we must do? • ‘I have established forever a true and lawful marriage between the empirical and the rational faculty…’ (GI, 15). Meaning?

11. Bacon, cont.—Inductivist? • ‘Directions for the interpretation of nature comprehend in general terms two parts: the first for drawing axioms from experience; the second on deducing or deriving new experiments from axioms’ (NO, II, x). • What method(s) is Bacon using?

12. René Descartes • Reasoned largely in a deductive (vs inductive) way from self-evident first principles; • Took his examples from mathematics and physics; • Treated contradictory data in a cavalier way, e.g. in explaining his laws of impact to Mersenne; • Not a ‘protagonist of the hypothetico-deductive method’ (McMullin 1990, 43).

13. Robert Boyle • Put the Baconian plan into practice—maintaining that accumulating facts was the first task; • Great experimentalist; used quantification; • Reported the actual experiments, not general statements as Galileo had done; • Formulated a guide to ‘good’ hypotheses: • Internally consistent • Explicate the phenomena • Contradict neither other phenomena or ‘manifest physical truth’, e.g. gravity.

14. Boyle, continued: • An ‘excellent’ hypothesis: • Simple (we would now say ‘parsimonious’); • Not ‘precarious’ or forced; • The best and/or only hypothesis that explicates the phenomena Boyle Joined induction and retroduction (hypothetico-deduction).