Rationalism and Empiricism

3 wave of doubt: senses, dreaming, demon (brain in a vat)

'cogito ergo sum'-I think therefore I am i.e. I only have access to the contents of my own mind

maths is true, regardless of dreaming, but not necessarily physical existence

CRITICISM

when we dream, we don't know but do know when we wake up

we can tell the difference between dreams and 'real life'

Innate ideas = to have certain inborn concepts e.g. defensive instincts

Innate knowledge - to know something is to have an idea that is true

The only things we know are a priori analytic?

Knowledge innatism entails innate ideas, but not the reverse e.g. we know an object is multicoloured but we must have a concept of colour to know that

Descartes

how can the idea of something so infinite and perfect be formed from ourselves who are imperfect and finite?

Trademark argument: God left the innate idea of himself in our minds so we can identify a creator

CRITICISM

God cannot be innate as not everyone believes in God

may come from different experiences we've been exposed to

G.E.Moore

morality cannot be gained from anything in the world as we can't reduce the concept of 'good' from anything we observe

we don't experience 'wrongness' or 'unfairness' from watching a fight, yet still have the concept of morality

CRITICISM

some people don't have morals

Plato

we never experience the physical number

if number isn't encountered in the physical world, it must be encountered in the 'ideal realm' or pure though, independent of the senses

Socrates and the slave boy-uneducated slave boy could do a maths question correctly-Plato argued the slave boy reasoned it as he was able to recall old knowledge instead of being taught

CRITICISM

some people struggle to grasp simple mathematics (Locke's "children and idiots")

Mill-maths is induction (we observe it)

Ayer-a priori analytic with no factual content-devoid of empirical content

Kant-a priori synthetic

Plato-knowledge = justified true belief

Plato

the forms are universals that more than one thing have e.g. beauty independent from beautiful things, beauty is always beautiful but not all instances are beautiful

we only have beliefs about instances, but knowledge about the forms must be from something other than experience-a priori

Trademark argument

we can know that He exists

Descartes

everything must have a cause as it's a matter of necessity

we don't experience everything in the world to know this

cause must be at least as complex or perfect as the effect

Leibniz

logical and mathematical principles are necessarily true and can be classified as innate knowledge

just because a person isn't aware of these principles, doesn't mean they don't possess it (in reference to Locke's "idiots and children")

Chomsky

children worldwide have a basic structure of grammar

e.g. applying plural of mouse as mices - extrapolation of grammatical structure, but hasn't been shaped by the English language yet

humans are able to contruct and infinite number of sentences, some that no one have ever previously said before-must be innate

Descartes

God proved through ontological argument and God wouldn't deceive us

CRITICISM

Locke

'tabula rasa'-how can you know something, but not know you know it?

objects of human enquiry divided into analytic propositions (Relations of Ideas) and synthetic propositions (Matters of Fact)

analytic propositions can yield knowledge whereas synthetic propositions can be no more than belief

maths and logic (analytic) cannot tell us anything about the world, nothing about the world can be known a priori

synthetic propositions e.g. the grass is green, aren't discoverable by reason, so must be by experience

 we are born 'tabula rasa'

we learn everything by experience

our ideas: complex ideas = many simple ideas from our experience

e.g. God = goodness + love + father figure + justice + power

we augment, diminish, compound, transpose and negate simple ideas

if you cannot experience something you can have no idea of it i.e. if someone lacks the sensory apparatu to have an experience, they can never have the corresponding idea e.g. a blind man has no notion of colour therefore there can be no a priori ideas

CRITICISM

missing shade of blue-man can form simple ideas of the missing shade although they haven't experienced it

ideas e.g. justic, morality and beauty cannot be experienced or broken down

at what point do you stop breaking down?

not tabula rasa, but a block of marble with veins running through it i.e. innate ideas are present but need to be uncovered through experience

experience shapes what's innate

CRITICISM

solipsism-we cannot be certain of what we experience

we experience the world indirectly (through sense experience) and can only know for certain I exist and have sensations

Karl Popper

mind is a searchlight rather than a bucket i.e.we have to actively process our experiences rather than them just filling up our mind

our mind is not that passive

mind organises experience

phenomenal world (world we experience) and noumenal world (world as it is)

basic conceptual schemes:

matter

time and space

causation

unity

'we know a priori that every event has a cause'-the proposition is not true by definition so is synthetic a priori

causation is a pre-condition of experience so we know everything has a cause a priori-we know this through rational intuition or insight

our knowledge of space is prior to experience and Euclidean geometry tells us all we need to know about space

CRITICISM

it was found there are different geometrical systems and the universe doesn't conform to Euclidean geometry so our intuitions are wrong

HOWEVER

Kant isn't saying how the world us, but how we perceive it, space is 4D but we perceive it as 3D

paradigm shift-something that drastically changes what we thought we knew e.g. the Earth revolving around the sun

realism-one true reality we can be right or wrong about

relativism-equal belief systems e.g. magic, science or religion

Kuhn-paradigms cannot be translated into another-different people and cultures have radically different worldviews or conceptual schemes so they cannot be understood by one another e.g. Eskimo words for snow

(thought depends on language and language defines our thoughts)

'the limits of my language are the limits or my world'

linguistic relativism-the world has no structure of its own, but its structure is entirely influenced by language

language determines our concepts and we can only think through concepts (linguistic relativism) e.g. English uses 11 colour categories, and Jale (New Guinea) uses 2

CRITICISM

Whorf hypothesis is exaggerated and though that cultures can learn words for 'missing' colours; there are similarities on how people interpret colour which are greater than the differences

HOWEVER

Whorf studied a Hopi speaker living in New York and concluded Hopi's don't use tense in their sentences so must have a different sense of time, so criticises Kant's claim that time is a priori

languages, especially grammatical structure affects thought, questioning Kant's claim there are universal structures for conceptual schemes

Indian philosophy has similarities with Western philosophy as they have similar linguistic origins

CRITICISM

if language conceptual schemes are relative, how can we understand how each other see the world?

a priori

truths that can be known independently of experience without the use of senses

a posteriori

truths that can only be know via the senses

analytic (tautologies)

sense that can be shown to be true by examining the terms involved

cannot be denied without a contradiction

predicate is involved in the subject e.g. a bachelor (subject) is a unmarried man (predicate)

these truths are true by definition

synthetic

truths not shown to be true by the meanings of terms

need experience to be known so are a posteriori

predicate adds something to the subject

can be denied without contradiction

necessary

truths that are possible in all worlds or possible situations

e.g. 2 + 2 = 4, NOT 'the sky is blue'

contingent

truths that might have been otherwise

e.g. 'the sky is blue'

deduction

a type of reasoning where if the premises are true, the conclusion must be true

cannot accept the premises but not the conclusion

deductive arguments don't tell you anything not already included in the premises

induction

type of reasoning that is based on the idea that things we have not yet experienced will resemble what we have experience e.g. all swans are white (generalisation)

how science works

the more evidence, the stronger the argument

never give you certainty as you can't have an infinite number of examples to support your case