Hobbes, Galileo & Descartes were friends. They were from different countries (England, Italy and France(. They had different specialties, styles and beliefs. But they shared a love for science and the importance of rational thought.
Together, this trio formed the basis for rationalism. Got a problem? Think things through. In contrast to the experience your way through life approach of the empiricists, rationalists believed in the power of deduction. Here’s a quick overview.
Hobbes, Thomas (1588-1679)
He was born in Malmesburg, England, where his father was a vicar. Malmesburg, built in 640, is in western England, along the Avon river. It’s closer to Bristol than to London, and the surrounding region of Wiltshire is best known for the Stonehenge megalith. When Hobbes was quite young, his father deserted the family, leaving them to fend for themselves. Fortunately, Hobbes was supported by his uncle, a wealthy glover, who paid for the boy’s education in private school and at Oxford. After graduation, a wealthy family hired Hobbes as a private tutor and he traveled widely with them.
In 1636, at the age of 47, Hobbes visits Galileo in Florence and comes away convinced that the universe is composed only of matter and motion. For him, man is a machine whose mental activity was reducible to the motion of atoms in the brain, and free will, spirit and mind are illusions.
Although Hobbes was friends with Francis Bacon (and served as his secretary for a short time), he rejected Bacon’s inductive reasoning in favor of the deductive methods of his other friends (Galileo and Descartes). He builds his case as a chain of deductive proofs.
Thomas Hobbes is best known for his “trains of thought,” his Laws of Nature, and his emphasis on social contracts. According to Hobbes, ideas tend to follow each other, like cars of a train. These “trains of thought” are often unguided and rambling but they become orderly when two ideas are similar. One association leads to another, like train cars all coupled end to end, forming trains of thought. Although the metaphor was new, the concept of association dates back to ancient Athens. Hobbes reintroduced Plato’s and Aristotle’s explanation of learning by wrapping it in an undated package.
Hobbes proposed that there are Laws of Nature that govern human interaction. These laws are society’s way of countering the essential selfishness of people. Although these laws coincide with God’s commands, they can be discovered by reason alone and should be obeyed for purely secular reasons. For Hobbes, people are motivated by selfishness. Even good behavior is the result of personal selfishness. Good behavior leads to good internal feeling. Consequently, we do good things because we derive some internal benefit. Nature’s laws, which include the laws of peace, duty, and gratitude, are to be followed because it is in our best interest to be at peace. Moral laws are social contracts we make with other people for our mutual benefit.
For Hobbes, one thing leads to another. Just as one idea is linked to another to form a train of associations, one principle leads to another, like proofs of mathematics. Laws of Nature are connected to social contracts. Hobbes maintains that because people are basically selfish, they enter into social contracts with others out of self-preservation. Morality is a matter of convenience and survival. Nature is in a constant state of war and quarrelsomeness, so people form contracts (I won’t steal from you if you don’t steal from me) in order to survive. It is these social contracts that form the basis of civilization.
Hobbes’ ideas were quite radical. He combined the British empiricism of Bacon and the continental rationalism of Descartes. He emphasized the importance of sensory perception and experience but used the deductive reasoning and mathematical forms of geometry more characteristic of the continental thinkers. Because of his ideas, Hobbes was often at odds with those in power. From 1640-1651, he fled to France, fearful for his life. In 1667, the British House of Commons was readying a bill outlawing blasphemous literature. Hobbes had the dubious distinction of having his work Levianthan cited as an example of what should be banned.
Galileo (1564-1642)
Galileo, a one word name like Elvis, was a philosopher, scientist and, indirectly, theologian. Born in Pisa, Italy, home of the famous leaning bell tower, received his medical degree from University of Pisa. He would have been of the leaning tower but probably didn’t drop any objects off of it to prove principles of physics.
In 1589, Galileo became the chair of the mathematics department at the university. About 25 years later, the Catholic Church arrested him, labeled him a heretic and kept him in house arrest until his death.
The problem was Aristotle. Galileo’s observations of the real world didn’t match Aristotle’s theory . Aristotle held that the universe is immutable (unchangeable), has always existed and revolves around the earth. There was no big bang, no moons or planets revolving around each other or anything but earth. Stars were decorative, and the moon is a translucent ball hanging like an ornament in the sky.
Several things happened. There were the super-Novas of 1572, 1601 and 1604. These were big events that couldn’t be ignored. There was the increased interest in science, and the rapid gain in knowledge and technology. Although he didn’t invent the telescope, Galen was an early pioneer in its construction and use. In 1609, his first telescope. It was a tube with a convex lens at one end and a concave eyepiece at the other. The first model had 3x magnification but was soon improved to more than 20x. These improved Galilean telescopes were manufactured and sold by Galileo himself.
Technology always brings challenges. New telescopes brought new observations. In November of 1609. Galileo points his telescope at the moon. He discovers the moon has mountains and craters, which he proceeds to map. Later, he sees that Jupiter has moons which orbit it. And many scientists conclude that the sun is the center of our solar system (not Earth), there is a Milky Way, and we are not in the center of everything.
The philosophical basis for his work was rationalism. He believed in God, and that people were designed to think, explore and explain the Creator’s work. Science and religion don’t stand at odds. They work together. The problem with theologians and philosophers writing the science curriculum is their assumptions can be wrong. Science requires an open mind to what exits in reality. When there is a conflict between science and theology, change your theology.
It seems iftting that Galileo lived in Pisa, where a religious building was constructed on shaky ground. There is a parable of a wise man building his house upon a rock, in contrast to a foolish man building his house upon the sand. It turns out, a good foundation is needed for building good scientific theories, good theologies, and good non-leaning bell towers.
Galileo died 9n Pisa in 1642, at the age of 77.
Descartes, Rene (1596-1660)
Born in La Haye, France, René Descartes came from a wealthy family but was in poor health for most of his life. His mother died with he was very young; his father (a lawyer) traveled a lot) He was raised by his grandmother, together with an older brother and sister.
Educated at the College of La Fleche (a Jesuit school), Descartes believed that God created the universe, set it in motion, and left it alone. He held that since God was not involved in the day to day operations of the universe, it is possible to study the universe and its laws without making theological statements.
Descartes maintained that animals were basically machines but man has a soul. The body operated like the fountain at St. Germain (outside of Pairs) with its mechanical statues. As people walked on the stones near the fountain, they triggered hidden plates under the stones that were attached with strings and levels to valves that released water through tubes that make the statues move. Similarly, the human body has senses that are connected by thin strings to cavities. Pulling on the strings (stimulating a sense) caused the cavities (ventricles) to release gases to flow to the muscles and move the body. The strings are inside of hollow tubes (nerves) and the gasses were thought to be distilled from blood and were called animal spirits (in the same way that drinks which contain distilled alcohol are called distilled spirits). Just as God is a spirit and can travel anywhere instantaneously, animal spirits move animals and travel instantaneously through the hollow nerve tubes.
The eyes were thought to be connected to directly to the pineal gland. Descartes was a dualist (both body and soul exist) and reasoned that the soul and the mind had to meet somewhere. He proposed that the pineal gland (since it has no duplicates) was where the meeting occurred. The eyes send gasses through the nerves to the pinal gland and make an impression of the scene; that’s why the eyes are the “mirror of the soul.”
After Descartes earned his law degree from the University of Poitiers in 1616,. he set off to see the world. He traveled through Brittany, Switzerland and Italy, and served a volunteer solider for Maurice of Nassau, and for the Duke of Bavaria. On November 10, 1619, Descartes had an encounter with God. In a dream, he had a vision that God was going to reveal all knowledge to him. Descartes’ revelation was that all of the different areas of knowledge can be unified by a single method of reasoning. The method that came to him began with a search for absolutes.
To build a unified body of knowledge, one must start with the smallest parts. These building blocks must be the clear, un-doubtable and simple (not composed of other ideas). From this base of absolute knowledge all other knowledge can be deduced. Descartes searched for the smallest parts of knowledge by systematically doubting everything. In 1629, Descartes, living in Holland, came the end of his search. He had doubted everything, even whether he existed. The only idea he couldn’t doubt was that he was thinking. Consequently, his existence could be assured; “I think, therefore I am.”
In contrast to scholasticism (demonstrating the logical validity of truths), Descartes believed his approach allowed the uncovering of truth. Syllogisms were only useful after a discovery has been made (revealed by authority). Descartes rationalism rejected that reliance on authority (since all authority is flawed). His approach, called the Cartesian method, used both intuition and deduction. Intuition is pure reason (understanding an idea directly, not through the senses); deduction uses memory and draws conclusions from a continuous chain of thought (A to B, B to C, etc.).
Although a rationalist (noting the faultiness of sensory perceptions), Descartes accepted both innate ideas and empirical observations. According to Descartes, knowledge of God is innate, supported by reason (perfect ideas can’t come from something imperfect, so they must come from God). Similarly, even though perceptions can be faulty, experiments in physics, biology and physiology provide confirmation of an ideas validity. Ideas must be tested in reality. Indeed, Descartes believed that all of science is a tool for bettering human life; ultimately, theory must be turned into practical applications (e.g., ethics, medicine, mechanics).
Descartes’ discovery of analytic geometry had both theoretical and practical consequences. While lying in bed, he was idly watching a fly in his room. Descartes noticed that he could describe the fly’s location with only 3 numbers (one for each dimension). From a theoretical perspective, this coordinate system integrates geometry and algebra. In practical terms, it allows a mathematical description of planets in their orbits, arrows in flight and people in their environment.
Experimental Physiology
Want to jump ahead?
- Philosophical Roots of Psychology
- Waves & Schools of Psychology
- Old Philosophers, New Ideas
- Hobbes, Galileo & Descartes
- Experimental Physiology
- American Psychology
- Japanese Psychology
- German Psychology
- Russian Psychology
- Five Paths To Truth
- Birth of Psychology
- British Empiricism
- British Psychology
- French Psychology
- Wundt
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