Reason as a source of knowledge 3.1.3 (copy)

innatism, the intuition/ deduction thesis

empiricism

all knowledge comes from experience

rationalism

we can acquire some knowledge through intuition and deduction/ by thinking rather than perceptal experience

innatism

says we are all born with some knowledge already

analytic truth

true in virtue of the meaning of words

example of an analytic truth

“A triangle has 3 sides”

synthetic truth

true in virtue of how the world is

example of a synthetic truth

“Grass is green”

A priori knowledge

knowledge that can be acquired without experience of the external world, through thought alone

A priori knowledge example

working out that 900 divided by 7 is

A posteriori knowledge

knowledge that can only be acquired from experience of the external world

A posteriori knowledge example

doing an experiment to discover the temperature at which water boils

intuition

the ability to know something is true just by thinking about it

deduction

a method of deriving true propositions from other true propositions (using reason)

necessary

one that must be true, cannot not be true regardless of situation

example of necessary condition

2+2=4

contingent

one that could be true or false depending on circumstances - the world could have been different

contingent example

I am in room 823 (contingently true as it could become false)

Is innate knowledge a priori or a posteriori knowledge?

A posteriori as innate knowledge is knowledge you’re born with

what is Meno’s paradox?

states that it is impossible to learn anything as everything you might learn either you already know it or you don’t know about it

What is Plato’s Meno?

to prove his theory that we’re born with innate knowledge and just need to remember it, Plato shows how Meno’s slave- a boy who has never been taught geometry- is able to understand geometry proof.

Outline the slave boy argument

P1: Slave boy has no prior knowledge of geometry

P2: Socrates only asks questions- doesn’t teach boy

P3: After questioning, slave boy can grasp eternal truth about geometry

P4: eternal truth is not delivered from boy’s prior experience nor from Socrates

C: eternal truth must have existed innately in boy to begin with

What does Leibniz believe about innate ideas>

believed innate ideas only become fully formed via experience

explain Leibniz’s marble analogy

compares our minds to a block of marble that has veins through it and when chiseled it will readily take a specific shape- we are not born with innate ideas fully formed since we need the experience (chisel) of the senses to gain ideas

Locke’s 3 responses against innate ideas

1. innate knowledge would be universal/ no universal assent

2. transparency of ideas

3. how can we distinguish innate ideas from other ideas?

Describe Locke’s argument of ‘innate knowledge would be universal’

• Locke argues that if we did have innate knowledge then every human would have such knowledge

Locke argues children and ‘idiots’ do not possess such knowledge- e.g. they don’t know theorems of geometry

Leibniz response to Locke’s idea ‘innate knowledge would be universal’

children and ‘idiots employ innate principles in everyday actions even if they can’t articulate them, for example: child knows a teddy cannot be in hand and loft at the same time

Describe Locke’s argument of ‘transparency of ideas’

if we did have innate ideas- like the idea of God-they must be present in our minds at some point, Locke claims our minds are transparent and we can perceive any ideas they contain- if you’ve never had an idea then how can it be ‘in’ your mind

Leibniz response to Locke’s idea ‘transparency of ideas’

there are many things in your mind you have never been conscious of, for example you may have absorbed a song on the radio that may not be transparent in your mind yet may be recognizable when heard again- same with innate ideas

Describe Locke’s argument ‘how can we distinguish innate ideas from other ideas?

how can we distinguish some of our innate ideas from some of the ones gained from experience

for example: why not say the colour blue was in you from birth but only when seen does the idea become active

leibniz response to Locke’s idea ‘how can we distinguish innate ideas from other ideas’

innate ideas are true in a different way- they are necessarily true- young children may not know truth of maths , once they understand a truth, mind recognises it has eternal application

tabula rasa meaning

blank slate

Who argues the tabula rasa after rejecting innatism?

Locke

Locke argues the mind at birth contains no ideas, thoughts or concepts, instead knowledge comes from what 2 types of experience?

1. Sensation- our sense perceptions- see, hear, smell etc

2. Reflection- experience of our own minds- thinking, wanting, believing etc

what is the tabula rasa theory based upon?

Ockham’s razor

tabula rasa argument

P1: the theory of innate ideas claims we are born with innate ideas

P2: All of our ideas can be shown to be derived from experience (tabula rasa)

C: theory of innate ideas= redundant

Describe idea of Ockham’s razor

the idea that, wherever possible we should always go for the simplest explanation- we shave off the unnecessary elements to an explanation

simple concepts example

when I look at a clear sky, my sensation of blue may give concept of blueness

complex concepts

made from simple concepts

complex concepts example

concept of the oceans consists of simple concepts of blue and cold

abstract ideas/concepts

complex ideas beyond specific instances- we can form a general concept by ignoring irrelevant features e.g. colour and abstract common features

What does Locke claim about all concepts?

they are delivered from experience and are not innate

2 parts to Hume’s fork

1. Relations of ideas

2. Matters of fact

3 criticisms of the tabula rasa

1. Do all simple ideas come from impressions?

2. Do all complex ideas relate to impressions? (relational concepts)

3. Do some concepts have to exist in the mind before sense impressions can be properly experienced?

explain criticism 1 of the tabula rasa: do all simple ideas come from impressions?

Is it possible to imagine any shade of blue having only seen 1?- Hume argues you can fill in a missing shade in a range of blues as perhaps the missing shade is in us innately from birth

Response to criticism 1 of the tabula rasa

1. Maybe you have formed a complex concept- missing shade would be formed from simple concepts

2. We cannot form missing shade- we cannot form something without encountering it

explain criticism 2 of the tabula rasa: Do all complex concepts relate to impressions?

we seem able to have a concept of something without ever experiencing it- I can have a concept of tea without have ever drinking it - the concept of sameness doesn’t have a particular colour or taste and cannot be related to specific impressions

explain criticism 3 of the tabula rasa: Do some concepts have to exist in the mind before sense impressions can be properly experienced?

Kant argues we experience the world as a series of objects interacting in causal ways because your experience has the concepts of unity/ space/ time/ causation already applied to it- we have existing innate concepts that enable experience to happen

Chomsky on criticism 3 of the tabula rasa

our minds have innate structures in place to learn language so effectively as children

clear idea

an idea is clear if it is very bright and present to the mind

distinct idea

an idea is distinct if it is sharply separated from other ideas

example of a clear and distinct idea

I am thinking

intuition

‘look upon’- an act of intellect whereby it inwardly ‘looks upon’ and intellectual object e.g. triangle and instantly sees its true features

deduction

build up arguments systematically in the right order to allow the mind to arrive at further truths

According to Descartes we should accept only beliefs that can be recognised…

clearly and distinctively to be true

3 criticisms of intuition/ deduction, clear and distinct idea

1. terms are not clear and distinct enough- Leibniz relying on feeling isn’t enough

2. quick generalisation- generalises his cogito and claims any belief he can conceive with c&d ideas must be true

3. only internal criteria for truth- Ryle says this approach is mistaken

Descartes 3 waves of doubt

1. Illusion

2. Dreaming

3. Deception

Outline Descartes’ cogito

P1: I am thinking

P2: All thinking things exist

C: Therefore, I exist

cogito ergo sum

I think therefore I am

Descartes denies the cogito is deduction but rather what

a simple intuition of his mind that is self evident

how is the cogito a priori

it can be known independently of experience as it is a self-justifying thought

Summary of Trademark argument

• argues concept of God is like an innate trademark placed in our minds

• God could only have appeared in his mind if there really is a God, like a logo on a t-shirt reveals its maker

• infinite being cannot be produced from mind of finite being

Outline Descartes Trademark argument

P1: The cause of anything must be at least as perfect as its effect

P2: My ideas must be caused by something

P3: I am an imperfect being

P4: I have the idea of God, which is that of a perfect being

IC1: I cannot be the cause of my idea of God

IC2: Only a perfect being can be the cause of my idea of God

C: God must exist

3 empiricist responses of trademark argument

1. casual principle (Hume’s fork)

2. not a priori

3. idea of perfection

criticism of the Trademark argument: casual principle

Descartes believed it self-evidently true that ‘the total cause of something must contain as least as much reality as does the effect’- not clear how this applies to world of ideas, our minds can easily create better versions of real objects

• Hume argued our idea of God derived from considering virtues of other people

• shows this premise is a matter of fact not relation of idea and so is a posteriori- fails to establish rationalism- Hume’s fork

criticism of the Trademark argument: not a priori

Hume: we can never deduce the effect from examining the cause or vise versa, we need experience of constant conjunction- only known through experience

criticism of the Trademark argument: idea of perfection

we do not have a clear concept of a perfect God or infinity- these concepts are not present in our minds

Outline Descartes’ contingency/ cosmological argument

P1: The cause of my existence as a thinking thing must be a)myself b) I have always existed c)my parents d) God

P2) I cannot have caused myself to exist for then I would have created myself perfect

P3) Neither have I always existed as I would be aware of this- I do not have the power to cause my continued existence

P4) My parents may have been the cause of my physical existence yet not of me as a thinking mind- cannot be an infinite series of causes

C) by elimination, therefore, only God could have created me

empiricist criticism of contingency/ cosmological argument: not a priori

• both resemble abductive arguments , they start from observations about how the world is- matters of fact not relations of ideas

• Hume’s objection to causation: constant conjunction

criticism of contingency argument

could we have been created by another conscious being less great than God- options given are not exhaustive

Outline the ontological argument

P1: I have an idea of God, as a perfect being

P2: A perfect being must have all perfections

P3: Existence is a perfection

C: God exists

2 criticisms of OA (covered in metaphysics of God)

1. Guanilo’s perfect island

2. Kant- existence is not a predicate

empiricist response to OA: Hume’s fork

claims about the existence of any object will always be matters of fact- the most the OA shows is that the idea of God contains existence

Outline Descartes proof of the external world- part 1a

P1: The will is a part of my essence

P2: Sensation is not subject to my will

C: Sensations come from outside of me

Outline Descartes proof of the external world- part 1b

P1: My nature or essence is unextended

P2: Sensations are ideas of extended things

C: sensations come from outside me

Outline Descartes proof of the external world part 2: sensations originate from matter

P1: There are 2 possible sources for the origin of sensation: God or matter

P2: I have strong inclination they come from matter and I have no faculty by which to correct this belief

IC: if there origin was within God, God would be a deceiver

P3: God is not a deceiver

C: sensation originates in matter

criticism of 1a

perhaps sensations come from a part of me for which I am not conscious e.g. like dreams not subject to our will yet they come from within us

criticism of 1b

it is not obvious that an unextended thing could never produce the idea of an extended thing- Descartes relies on casual principle- we can perceive extended things even though our minds are unextended

criticism of step 2

Berkley- perhaps God feeds ideas of material things into our minds, Descartes rejects this on the grounds it would be a deception from God but for Berkley there is no deception

criticism God might not exist

Descartes proof relies on his earlier arguments- which empiricists such as Hume would attack

criticism other ways of establishing existence of the world

Russell and Locke: physical world is the best option