- Archimedes’ book on mathematics and physics was translated from the Greek and became widely read for the first time;
- The Structure of the Human Body, a book of Andreas Vesalius’ anatomical drawings, provided the first accurate look at human anatomy;
- The Revolution of the Heavenly Spheres, by Nicolaus Copernicus, presented the concept of a heliocentric cosmology and set the scientific revolution in motion, as its author lay on his deathbed.
Giordano Bruno (1473-1543) advocated this Copernican universe and was burned at the stake. A century later Galileo strongly argued for a Copernican universe. He was tried by the church and threatened with excommunication, he was forced to recant, and he spent the rest of his life under house arrest. Later scientists, particularly Kepler and Newton, concluded the battle with less adverse personal impact. Bronowski [1973] calls Galileo the “creator of the modern scientific method” because in 1609-1610 he designed and built a 30-power telescope, used it for astronomical observations, and published the result. I see Galileo not as the creator but as one who exemplifies an important phase in the evolution of modern scientific method.
Galileo valued experimental verification of ideas. In the 17th century, Francis Bacon, René Descartes, and others succeeded in steering science away from mysticism and confining scientific research to topics that are verifiable, by either the senses or deduction. Indeed, even the 17th-century scientific genius Isaac Newton devoted part of his life to alchemy. When researchers adopted the pragmatic attitude of giving priority to what is observable with the senses, they took one of the final steps in development of modern scientific method.
The early 17th century saw a watershed collision of two philosophies of scientific method: deduction and experimentation. René Descartes’ [1637] book Discourse on Method emphasized mathematical deduction and laid out the following four principles of his scientific method:
- “never accept anything as true if I had not evident knowledge of its being so. . .
- divide each problem I examined into as many parts as was feasible. . .
- direct my thoughts in an orderly way; beginning with the simplest objects. . .
- make throughout such complete enumerations that I might be sure of leaving nothing out.”
In contrast, Francis Bacon’s [1620] book Novum Organum sought to establish a new empirical type of science. He argued compellingly that science cannot be confined to either deduction or observation; one must use a combination of experiment and hypothesis, testing hypotheses empirically.
“All true and fruitful natural philosophy hath a double scale or ladder, ascendent and descendent, ascending from experiments to the invention of causes, and descending from causes to the invention of new experiments.” [Bacon, 1561-1626]
Both approaches had strengths and weaknesses, and both contributed to modern scientific method. Bacon, who was not a working scientist, failed to realize the importance of intuition in creating hypotheses and of judgment in rejecting most hypotheses so that only a subset need be tested. Descartes sought to confine science to those areas in which mathematics could yield ‘certainty’:
“Science in its entirety is true and evident cognition. He is no more learned who
has doubts on many matters than the man who has never thought of them; nay he appears to be less learned if he has formed wrong opinions on any particulars. Hence it
