KNOWLEDGE & METHOD IN 17TH C:  RATIONALISM & EMPIRICISM

EMPIRICISTS             RATIONALISTS                SKEPTICS

Francis Bacon              René Descartes                Pierre Bayle
(1561-1626)                   (1596-1650)                     1697 Historical & Critical Dictionary

John Locke                  Leibniz                              David Hume 18th C. Enlightenment
(1632-1704)                  (1646-1716)                         On Human Understanding,  Natural Religion                  

ACADEMIES OF SCIENCE –   1660 Royal Society in London (Charles II)
                                             1666 Académie Royale des Sciences in Paris   (Louis XIV) 

METHODOLOGIES:  INDUCTIVE versus DEDUCTIVE

FRANCIS BACON (1561-1626)  1620  Novum Organum
                                               1627  New Atlantis
     spokesman for British empirical tradition: inductive method
     attack on IDOLS OF THE MIND: various kinds of "received ideas"
        Idols of tribe (human wishes); Idols of cave (individual errors)
        Idols of marketplace (collective, common sense errors)
        Idols of theater (errors of systematic philosophy, philosophic systems as “stage plays”)
       versus
direct observation, experiment as best method to learn about nature
       purpose of knowledge: to subdue and dominate nature for human benefit
       creation of universal natural history: finite task, assemble all the “facts”

RENÉ DESCARTES (1596-1650) French, deductive method; educated by Jesuits
      Mathematical model: analytical geometry, Cartesian coordinates
                          esprit géométrique = geometrical spirit
       1629-49: in self-imposed exile in Holland; fear of censorship

Discourse on Method (1637)
      DUALISM: MIND  versus MATTER -
               two kinds of “created substances” in universe
               GOD as guarantor of our perceptions, “uncreated substance”
      Procedure of methodical doubt: dream hypothesis, demon deceiver
      Cogito ergo sum: (I think therefore I am) awareness of self as mind
      Principle of clear & distinct ideas as criteria of certainly

External physical world:  matter (extension in space) & motion
Mechanical understanding of nature: laws of nature are mechanical
Animals as automata: mechanical beings, no mind or spirit

JOHN LOCKE  (1632-1704) British empiricist
          Epistemology: theory of knowledge; how do men know what they know?
          Writes against Descartes’ system as abstract and deductive:
                  instead “plain historical method” of how knowledge enters mind
                  (similar to hypothetical “historical” explanation of govt’l origin
1690 Essay Concerning Human Understanding:
            sensation as basis of knowledge; mechanical process
            sense perception creates traces, grooves on brain
            experience organizes these perceptions into knowledge over time
        human mind as tabula rasa  (blank slate) until sensory data enters
                  rejection of innate ideas (as in traditional Platonism

Religion: On the Reasonableness of Christianity
                Letter Concerning Toleration

ISSAC NEWTON (1642-1706) founder of modern physics
             Calculus: ability to measure motion, speed, rates of change over time
             Scientific method: combines empiricism + mathematical rationalism
             1687 Principia Mathematica: mathematical principles of natural philosophy

Three laws of motion: 1) inertia: tendency of a body to remain at rest,
    or in  motion with constant velocity, unless acted on by external force;
2) force = mass times acceleration;
3) for every action, there is an equal & opposite reaction

Alexander Pope: “Nature and nature’s laws lay hid from sight,
                             God said, ‘Let Newton be,” and all was light.”