were better not to study at all than to occupy one’s self with objects of such difficulty, that, owing to our inability to distinguish true from false, we are forced to regard the doubtful as certain; for in those matters any hope of augmenting our knowledge is exceeded by the risk of diminishing it. Thus . . . we reject all such merely probable knowledge and make it a rule to trust only what is completely known and incapable of being doubted.” [Descartes, ~1629]
This deductive dogmatism is incompatible with almost all of modern science; even theoretical deductive physics begins with unproven premises. In the 17th century, however, the outcome of the battle over the future direction of science could not be predicted.
Antoine Arnauld [1662], in an influential book on logic, presented a pragmatic approach to scientific and other judgment: rational action, like gambling, is based not on Cartesian certainty but on consideration of the probabilities of the potential outcomes. Isaac Newton [1687] reinforced the Cartesian perspective on science with his book Principia Mathematica . Considered by some to be the most important scientific book in history, Principia established a new paradigm of the physics of motion, drawing together a very wide suite of observations into a rigorous mathematical system. Newton was primarily a theoretician, not an empiricist, but he eagerly used data collected by others.
Eventually, the conflict was resolved: with the edges of the road defined, a middle way could be trod. John Locke argued persuasively that experimental science is at least as important as Cartesian deduction. Locke became known as the ‘father of British empiricism.’ ‘Champion of empiricism’ is probably a more appropriate epithet, however, for Locke made no important scientific discoveries. Locke provided the needed scientific compromise: certainty is possible in mathematics, but most scientific judgments are based on probable knowledge rooted in controlled experiments. Each person must evaluate open-mindedly the evidence and make a personal judgment.
“The mechanical world view is a testimonial to three men: Francis Bacon, René Descartes, and Isaac Newton. After 300 years we are still living off their ideas.” [Rifkin, 1980]
Isaac Newton [1676] wrote to Robert Hooke, “If I have seen a little further it is by standing on the shoulders of Giants.”
Bernard of Chartres [~1150] wrote, “We are like dwarfs sitting on the shoulders of giants; we see more things, and things that are further off, than they did -- not because our sight is better, or because we are taller than they were, but because they raise us up and add to our stature by their gigantic height.”
Remarkably, scientific method has changed very little in the last three centuries.
Archimedes [~287-212 B.C.], emphasizing the power of the lever, boasted, “Give me a place to stand on and I can move the earth.” Of course, no lever is that strong. Even the 300-ton blocks of Egyptian and Middle American pyramids were beyond the strength of individual, rigid levers; recent research suggests the possibility that many flexible bamboo levers could have shared and distributed each load [Cunningham, 1988].
Three hundred years ago, the suite of scientific levers was completed. The world began to move in response.
