Building the Modern Mind - the Scientific Revolution
Paradigms and Paradigm Shifts
The Scientific Revolution is an example of a paradigm shift
Paradigm
A basic framework of ideas for understanding the world around us
A model for interpreting, organizing, and classifying information
Context for all thinking
Often unconscious acceptance of a perceived reality
Paradigms determine which questions can be asked and which can not
There is not one paradigm - we all work with several, that guide our thinking about many topics
Paradigm Shift
This occurs when one paradigm collapses and is replaced with another
This generally happens when the old paradigm encounters
significant problems or information it can not solve or explain
Ptolemy and Aristotle - The pre-Scientific Revolution paradigm for scientific knowledge
The basic scientific paradigm of ancient and medieval Europe depended primarily on two men - Aristotle and Ptolemy
Aristotle - Greek philosopher, 384-322 BC - established fundamentals of logic
Ptolemy - Greek astronomer, 87 -150 AD - developed a system for predicting movement of planets based on a geocentric (Earth-centered) universe
Features of the Ptolemaic/Aristotelian paradigm
Earth is at center of the universe
The heavens are perfect (hence, everything in the heavens is a perfect circle or a sphere)
Since Earth is clearly imperfect, it is very different from the heavens, and vice versa
Personal observation can be fully trusted (We know the Sun goes around the Earth because that's what it looks like it does)
Ancient thinkers are the best source of knowledge (particularly the Greeks, Romans, and the Bible)
Some aspects of the universe are inherently mysterious,
known only to God
Breaking down the Aristotelian/Ptolemaic paradigm
Old paradigm begins to disintegrate because of astronomy
Ptolemy had created a very complex system for explaining and predicting motions of planets in the sky
These worked well for centuries, but by the 1400s, his system had become increasingly unworkable and less reliable
Nicolaus Copernicus, Poland, mathematician, and astronomer (1473-1543)
Proposed in his book, On the Revolution of Heavenly Spheres (1543), that the problems with Ptolemy could be solved by putting Sun at center - heliocentric universe
Still mostly in old paradigm - kept planets moving in perfect circles, got his idea from ancient texts
Unfortunately, his system did a worse job of predicting motion of planets than Ptolemy
Galileo Galilei--Italy (1564-1642) astronomer
Believed Copernicus was right, set out to prove it
Used telescope to show Moon was not a perfect sphere (mountains and craters), that not everything circled the Earth (Moons of Jupiter)
By discovering Jupiter's four largest moons, showed that ancients did not now everything about the heavens
Also did experiments that disproved Aristotle's claim that light objects fell slower than heavier objects
Johannes Kepler, German astronomer, mathematician, 1571-1630
Led a very hard luck life
Inherited the astronomical observations of Europe's best astronomer, Tycho Brahe of Denmark (1546-1601)
Showed that motion of planets could be perfectly predicted if we assumed that traveled around the Sun in ellipses, not circles
Developed mathematical formulas to describe the motion of the planets - Kepler's Laws of Planetary Motion
Thus showed two things
The ancients were wrong about the heavens being made up of perfect circles and spheres
It was possible to develop mathematical formula to describe the workings of the universe
Isaac Newton--England (1642-1727) physicist, mathematician
Gained fame for work in optics
Invented calculus (Gottfried Wilhelm von Leibniz also did at same time - today we use Leibniz's notation system, not Newton's)
Publishes Principia in 1687 (Full title=Philosophiae naturalis principia mathematica)
Primarily concerned about gravity, motion of planets
Demonstrated that gravity in all places, here on Earth as well as in space, could be described with simple mathematical formulas
This gives us the idea of a universal natural law - that there are laws of science that apply everywhere, at all times and places
Implications of the Universal Natural Laws (UNL)
If the same laws apply everywhere, including the heavens, then Earth and the heavens are the same
Also, if there are UNLs about gravity, there are probably UNLs for everything else
In this time period, people began to think of UNLs as being like gears in a clock. If we can understand all the gears, we can understand all the universe, and potentially control it
In the past, that kind of knowledge belonged, in Western thought, only to God
Now inductive reasoning could find these laws
uniform observations are made and tested
these observations must be empirical - that is based on the concrete world we can detect with our senses
natural laws can then be inferred if predictable, repeatable patterns emerge from these observations
The New Paradigm
Sun is at the center of the universe (or course, this is later changed - Sun is out on the fringes of the galaxy, and there are billions of galaxies)
The heavens are not perfect - everything in the space is not a perfect sphere or circle
Earth is not different from the heavens - the rules here are the same as they are everywhere
Personal observation is potentially untrustworthy - your senses can fool you
Ancient thinkers did not know everything - it is possible to learn new things that they did not know
Scientific method (hypothesis, experimentation, verification, developing principles from experimental results) becomes key to new knowledge
Formally developed by Francis Bacon (1521-1626, England) but practiced by many, including Galileo
The universe is place we can fully understand and predict, and thus potentially control, because of the existence of universal natural laws
Much of universe can be described mathematically