Rene Descartes - 1596-1650 - was a contemporary of Galileo and is seen to be the founder of modern philosophy and his thoughts were based around and affected by the new physics and astronomy.When Descartes was old enough he travelled around Europe fighting in many wars that were happening in order for action to give him an insight, however, he was disappointed and so he embarked on an ambitious plan: to search for true meaning. Descartes was mainly a philosopher, but he also worked with mathematics and science. His most scientific book was Principia Philosophiae which was published in 1644, among other books, including Essais Philosophiques which focussed on optics and geometry published in 1637.
Descartes always wanted to make a discovery in medicine, he began by describing humans and animals as machines - animals = automata and are governed by physics as they have no conciousness. However, humans are different as they have a soul (pineal gland allows contact between the soul and body).
"I had gained nothing but an increasing recognition of my ignorance"
Even though this theory was abandoned by others it links in with the 'two clocks' theory. - ‘If mind and matter can’t interact, why does the body behave as if the mind is controlling it?' Geulincx's (Descartes' disciple) answer was the 'two clocks', if two clocks are kept in perfect time, so whenever one points to the hour the second clock will strike in order for one to seem as if it causes the other. SO with mind and body. Each is wound up by God, physical laws allow an arm to move although the mind has not exactly acted on the body.
Like with many theories, there are problems with this particular theory.
- as Russell states 'it was very odd'
- physicality was determined by natural laws and mentality runs parallel so it must be equally deterministic
- it would be hard for Christian ethics/the punishment of sin
As well as this, like many theories, it had its positives too.
- it made the soul completely independent of the bod
- it allowed 'one substance cannot act on another' - two substances (mind and matter) they are so different which made an interaction seem crazy.
Mechanics:
Descartes believed that chemistry and biology could be reduced down to only mechanics - when a seed develops into an animal or plant it is a mechanical process. He rejects Aristotle's three souls - there is only one (rational soul) and humans are the only ones who have it.
Discourse on Method and Mediations:
These are Descartes' most important books, published in 1637 and 1642. Descartes begins to explain 'Cartesian doubt'. As Russell says ' he resolves to make himself doubt everything that he can manage to doubt', so basically he doubted everything, well, everything except geometry because that was unchangeable. He regulated his conduct through the used of 'commonly received rules', which left his mind unhampered by consequences of the doubt.
-Cartesian Philosophy: 3 realms: mind/soul, matter (created substances) and God (uncreated substances).-
Doubt everything but God
Descartes started with scepticism, he asked whether he could doubt that he was sitting in a particular place wearing a particular item of clothing. The answer is yes, because he has dreamt that he was in that particular place wearing the particular item of clothing when in fact he was in bed.
Dreams present ideas that have been seen in reality - for example - you may dream of a horse with wings because you have seen horses and wings before in reality. Anything that may be sceptical can be doubted, your senses may deceive you.
Basically, is this all a dream? (the evil demon)
-doubting that you are thinking is still thinking-
This is where The Matrix comes in to it. It is a film based on Descartes' main philosophical way of thinking through the statement:
'I think, therefore I am'
and intellectual autonomy. In The Matrix the characters live a life through sensory information fed to them whilst in a pod which allows them to believe what they are seeing, touching, smelling, tasting and hearing is complete reality. Another filmic example could be Avatar where a whole other world is created through the senses.
Descartes considered ideas to be significant; here are the kinds:
- those that are innate
- those that are foreign and come from without
- those that are invented by me
Ideas are like outside things, about perception and they seem to be there.
The second type of idea is something that is an outside object - this is natural and it can also be derived by independence of the mind (sensation)
There may be two different of the same external object - the sun - in the way the senses see it (normal people) and the way astronomers see it. It is the same object but it has two different ideas.
Spinoza
Spinoza - 1632-77 - 'is the noblest and most lovable of the great philosopher' according to Russell. He wasn't as intellectual as other philosophers but his ethics topped that, which meant people thought he was wicked. His whole philosophy is dominated by God and the idea of God, however, Jews, Christians and Orthodox all rejected him.
Ethics:
Ethics was published after his death. It deals with three distinct matters: metaphysics, psychology of the passions and a ethic based on the preceding metaphysics and psychology. The metaphysics is derived from Descartes, the psychology is similar to Hobbes but the ethics is completely Spinoza's original work.
Metaphysics: there is only one substance - 'God or Nature' - Spinoza did not believe in Descartes' view on three substances: God, mind and matter and that in relation to God's omnipotence, mind and matter were two independent substances. Spinoza thought that thought and extension were attributes of God.
Everything is controlled by logical necessity. Spinoza believed that there is no free will in the mental sphere and chance in the physical world furthermore, he thought that everything that happens manifests from God's 'inscrutable nature'. There are negatives here, in regard to sin, if everything comes from God and is good then what about bad actions - Adam eating the apple, Nero killing his mother? Spinoza adds that what was positive in these acts was good and what was negative was bad.
Spinoza's emotions:
'the human mind has an adequate knowledge of the eternal and infinite essence of God'
Spinoza goes on to suggest that the 'passions' distract and obscure our intellectual outlook of everything. Love and hate - 'he who conceives that the object of his hate is destroyed will feel pleasure'. So, Spinoza suggests that if hate is destroyed, love is created through passion of the mind and according to Spinoza, self-preservation is the main motive of the passion shown. Self-preservation can alter in terms of its character when someone realises what is real and positive.
In the end section of Ethics, 'Of human bondage, or the strength of emotions and 'Of the power of the understanding, or of human freedom,' the most interesting points are made by Spinoza. Spinoza (like Socrates and Plato) believes that all wrong doing done is because of bad intellect.
Tractatus Theologico-Politicus was published in 1670 and is a combination of biblical criticism and political theory. Tractatus Politicus was published in 1677 after the death of Spinoza and deals with only political theory.
In biblical criticism, Spinoza predicts some modern views. He also shows that scriptures can be interpreted in ways that are compatible with liberal theology.
In political theory, Spinoza's views came from Hobbes. In state of nature there is no right or wrong because wrong is breaking the law, he also agrees with Hobbes that the Church should be subordinate to the state. However, he disagrees with Hobbes' view that democracy is the 'most natural' for of government. Spinoza believes in freedom of opinion but he thinks that religious questions should be answered by the state, not the Church...
Spinoza believes God is a necessary function:
'Love towards God...must hold the chief place in the mind.'
Leibniz
Leibniz - 1646-1716 - was according to Russell 'one of the supreme intellects of all time.' He believed that the world is the best of all possible worlds, because God is good and all powerful and he created and chose this world.
There are two systems of philosophy that are regarded to be part of Leibniz's work, one was 'optimistic, orthodox, fantastic, and shallow' whilst the other was 'profound, coherent, largely Spinozistic, and amazingly logical'.
Substance:
Leibiniz's most interesting philosophy can be found in the Monadology and the Principles of Nature and of Grace. The basis of his theological optimism is found in the Theodicee.
Leibniz based his philosophy on substance (much like Descartes and Spinoza), but his ideas on mind and matter differed. Descartes suggested that there were three substances (God, mind and matter), Spinoza said there was only one (God) and Leibniz suggested there is an infinite amount of substances known as 'monads'. Each of these monads would have some properties of a physical point when viewed abstractly, each monad is a soul. Leibniz inevitably denied the reality of matter.
God's Existence:
Leibniz had a metaphysical approach to the existence of God, which was started by Aristotle and Plato.
Ontological Argument:
This particular argument was rejected by St Thomas.
The distinction between existence and essence - Hamlet does not exist but he has a certain essence to his character - witty, melancholy etc. Here its essence does not mean existence but God is defined as the most perfect being - it is greater to exist than to not exist - so God exists.
Cosmological Argument:
This is a form of the First-Cause argument which comes from Aristotle's unmoved mover.
It points out -
- everything has a finite cause which had a cause and so on...
- the series of previous causes cannot be infinite
- the first term in the series must be uncaused (otherwise it is not the first term)
- There is an uncaused cause of everything = this is God
The Argument from Eternal Truths:
A statement such as - 'it is raining' or 'it is sunny' is sometimes true and sometimes false depending on the context of the day. However, statements such as - 'two + two = four' is always true, it is a fact. These truths are called eternal truths.
The Argument from the Pre-Established Harmony:
-This is only valid for those who accept Leibniz's windowless monads which mirror the universe.-
This argument states that, since all the clocks keep in time with one another without any interaction, there must have been a single outside cause that keeps the clocks like this. (an outside force or helper)
Every substances affects itself. But, because of God's interaction in the world, every substance interacts with every other substance - they all interact with each other. God has created a 'harmonized' world.
'I Think, Therefore I Am'
Western Philosophy of the 17th and 18th Centuries were divided into British Empiricism and Continental Rationalism.
Rationalists:
Descartes, Spinoza and Leibniz all believed in pure reason, the mind alone, or at least the pre-eminence of the mind.
Empiricists:
Locke - believed there were no innate ideas, people are born as a blank slate and that knowledge is gained through experience.
Bacon - the scientific method - believed in avoiding the idols of the mind.
Plato - believed that people are born with knowledge (opposite to Locke)
-Only source of knowledge is your senses.
Solipsists:
All is in an imagination and nothing actually exists.
Idealism:
Deny the existence of matter, everything is ideas.
For example - a chair - When looking at a chair I am aware of how the chair looks to me, not the chair itself. It is the effects that it produces within my mind when looking at it. - This can be used for touching and tasting etc.
- a falling tree - If a tree falls in a forest but nobody/nothing hears it fall, does it make a sound?
If someone answers yes - Materialist (only material exists)
If they answer no - Idealist
--> Berkeley - things flash in and out of existence, whether you are looking at a particular item/thing or not.
