John Locke

John Locke (1632-1704) was a 17^th Century English Philosopher and physician. He was regarded as one of the key thinkers in the enlightenment, and his theories developed epistemology (the nature and limitations of knowledge) otherwise known as the theory of knowledge. He is also considered to be one of the first british empiricists. The British constitution was based on his doctrines until 50 years ago, and his political theories which he wrote touched on life, liberty and property which appeared in the declaration of independence, which now exists in the American constitution. It must be mentioned that he was a deeply religious Christian who tied his faith in with his theories. He believed in the basic certainties of our own existence, the existence of god, and the truth of mathematics. 

His most famous work is his 'essay concerning human understanding'. The genius of the 'essay' is in it's assertion that men acquire knowledge not through divine revelation or because they possess innate ideas, but because the senses permit him to learn from the external world, and put him in touch with reality.

In my opinion these are the most important parts of Locke’s theory of knowledge:

      >Men are born as blank canvasses; knowledge is derived only from experience.

      >Self interest and the general interest coincide.

      >A man once educated will not act immorally.

      >Ideas are derived from 2 sources; sensation and perception or an ‘internal sense’

      >Perception is the first step towards knowledge

      >Everybody must always be moved, in action, solely by desire for his own happiness or pleasure

      >Private and public interests are identical in the long run.

‘’the necessity of pursuing true happiness is the foundation of all liberty’

Locke’s political philosophies consisted of 5 things; the hereditary principle, the state of nature and natural law, the social contract, property, and checks and balances.

     ‘The hereditary principle' - all men are created equal, all men entitled to equal rights whether it be  to land, life or liberty

      ‘The state of nature and natural law’ - ethicality of a man's actions, right to do something if a certain situation arises. ‘Natural law decides what actions would be ethically right and wrong, in a community that had no government; and positive law ought to be, as far as possible, guided and inspired by natural law’ – Bertrand Russell

      ‘The social Contract’ - ‘Civil government is the result of a contract, and is an affair purely of this world, not something established by divine authority’

            ‘Property’ - every man is entitled to have his own private property.

the Scientific Revival

In the chapter, ‘the rise of science’, in Bertrand Russell’s History of Western Philosophy it talks ultimately about Newton’s thoughts and findings on universal laws. But in order to understand Newton and his theories I have to understand all the early astronomers which caused the progression into his theories. These are the main points I have drawn from this chapter in order to understand how Isaac Newton came to his conclusion of universal gravitation.

The first Astronomer to take note of is Copernicus (1473-1542). Copernicus was a Polish ecclesiastic, but essentially hypothesised about astronomy. He came up with the initial idea that the sun is at the centre of the universe, and earth has a two-fold motion: a diurnal rotation and annual revolution about the sun. His most important book was called ‘De revolutionibus orbium coelestium’ and was published year of his death in 1543, this book displayed his hypothesis. His work can only be considered Pythagorean and not modern due to the fact that all celestial motions must be circular and uniform (not elliptical or having the ability to change direction). Also it had the absence of the stellar parallax, this meant that if the earth was 186,000,000 from the point it will be in six months, it will cause a shift in the apparent position of the stars. From this it can be assumed that he wasn’t aware of Aristarchus’s heliocentric theory. Despite being considered Pythagorean I believe that this was one of the first attempts to understand the universe through mechanics.

The second astronomer to note is Kepler (1571-1630). Now Kepler adopted the heliocentric theory and discovered three of the most important factors leading up to Newton’s findings. He discovered three laws of planetary motion, 2 of which were published in 1609, and the third in 1619. These laws where:

1)      Planets describe elliptic orbits, of which the sun occupies one focus

2)      The line joining a planet to the sun sweeps out equal areas in equal times

3)      The square of the period of revolution of a planet is proportional to the cube of its average distance from the sun

The striking thing about the first law is the change from the assumption which Copernicus held that planets orbit the sun in a circle motion. It was the first time that an elliptical orbit was mentioned. The second law essentially means that planets when orbiting speed up when nearer to the sun and slow down when further away. The third law explains how different planets all have their own movement patterns according to the equation.

The final Astronomer to consider before Newton which further expands on this knowledge is Galileo (1564-1642). Galileo was Italian and can be considered to be the founder of dynamics; he also adopted the heliocentric system. He discovered the importance of acceleration in dynamics. “Acceleration’ means change of velocity, whether in magnitude or direction; thus a body moving uniformly in a circle has at all times acceleration towards the centre of the circle.’ He also said that ‘everybody if left alone will continue to move in a straight line with uniform velocity; any change, whether in rapidity or direction of motion is done with ‘force’. This was enunciated by Newton as ‘the first law of motion’ or the law of inertia; it was the first idea of ‘force’ being able to change something’s ‘mechanical’ direction. He also established the law of falling bodies, which is; ‘When a body is falling freely, its acceleration is constant’ however ‘resistance of the air may interfere’ also ‘acceleration is same for all bodies, heavy or light, great or small.’

Sir Isaac Newton (1642-1727) was an English physicist, mathematician, astronomer and philosopher. He discovered that every planet, at every moment, has acceleration towards the sun which varies inversely as the square of the distance from the sun, acceleration towards the earth and sun. This explains the moons impact on the earth which is known as... Gravity! He described universal gravitation as a ‘force’ which is the cause of change of motion.

‘Everybody attracts every other with a force directly proportional to the product of their masses and inversely proportional to the square of the distance between them’ - Sir Isaac Newton.

From this theory he was able to deduce everything in planetary theory: the motions of the planets and their satellites, the orbits of comets, the tides and this essentially saw the change from medieval times to modernism, and a new wave of scientific theory and conclusions which we know today. His first law of motion deduced that lifeless matter, once set moving, will continue to move for ever unless stopped by some external cause the solar system, was kept going by its own momentum and its own laws. The earth was now seen as a minor insignificant planet opposed to the centre of the heavens as religion explained it, and a new sense of humanistic self-belief was incurred opposed to the self-hate which religion promoted.

The Renaissance

(Artistic depiction by Raphael of the school of Athens) 
shows all the important intellectual figures in ancient greece)

This lecture was basically a brief overview of the history and context of western philosophy. We looked at the the renaissance all the way from the scientific revival to Descartes’ cogito. Initially we looked at the difference between Plato and Aristotles beliefs. Plato believed in forms (ideals which exist outside time), he believed that our senses limit us to seeing the true form of everything around us, and we can merely see an imperfect copy of the world. Supposedly only the soul can see the true world around us.  Aristotle believed that in order to understand the world we had to understand the fundamental fact that Axioms exist, for example to attempt any kind of scientific equation or theory we must first realise that things are real. Descartes expanded on his theories...
   
The renaissance was a rebirth of classical thought and art, and was a self-conscious rejection of tradition, which was known as scholasticism. It argued for a more humanistic world view. Protagoras came up with the statement; “man is the measure of all things”. Prior to this point in time man and the body where seen as wicked and in need of salvation by the gods. From this point onwards man was seen as a being which could think for itself, and come to its own conclusions. One of the most important things about the renaissance was the ability to print information. With this new technology it was now possible to pass information from generation to generation; therefore people could expand on other people’s beliefs and ideas over thousands of years. This was necessary if any kind of progression was to occur.
   
There where supposedly two phases in which the renaissance occurred in Europe. The first was the South which saw witness to people like Machiavelli who was very hostile to Christian teachings; he can be seen as the beginning of political science, and a representative for renaissance humanism in the south. His most famous book is called ‘the prince’. In this he wrote about how people should rule, “it is necessary for a prince who wishes to maintain himself to learn how not to be good and to use this knowledge and not to use it according to necessity”. He came up with various rules for warfare as well for example; in a conflict always support the weaker side because when the conflict is over you will be the dominant power. This theory was actually proved correct and caused the eruption of the British Empire in the early 17^th century.
   
‘The age of reason’ marks the intellectual transition from the Middle Ages to the modern world. Descartes was another important philosopher. His belief was that the universe could be explained through mathematics, running along the same train of thoughts as Plato and Pythagoras. It was known as mechanical science. Sir Isaac Newton is a substantially important figure when it comes to mechanical science but he didn’t exist for another 100 years after this, so Descartes can be seen as the original mechanical scientist. Descartes loved mathematics because of “the certainty of it’s demonstrations and the evidence of its reasoning”. Obviously he was a very logical thinker. His true aim was “to arrive at knowledge of things a priori from the knowledge of the order of nature which controls them”. This is similar to Aristotle’s beliefs as it was necessary to have a fundamental certainty of the existence of himself and his thoughts.