An Epistemology Update John Rafferty MA MSc PGCE

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An Epistemology Update John Rafferty MA MSc PGCE Senior Lecturer Social Sciences Langside College

An Epistemology Update John Rafferty MA MSc PGCE Senior Lecturer Social Sciences Langside College Glasgow JRafferty@Langside. ac. uk Tel: 0141 272 3875

Section 1 Philosophical Issues in Epistemology

Section 1 Philosophical Issues in Epistemology

Outcome 1 n Demonstrate an understanding of the philosophical issues in the area of

Outcome 1 n Demonstrate an understanding of the philosophical issues in the area of epistemology: The Tripartite Theory of Knowledge n Philosophical Problems with the Tripartite theory n Scepticism, Rationalism and Empiricism n

Question 1 Why are knowledge claims a problem in philosophy?

Question 1 Why are knowledge claims a problem in philosophy?

Appearance and Reality n Perceptual problems • Colour blindness; hallucinations n Optical illusions •

Appearance and Reality n Perceptual problems • Colour blindness; hallucinations n Optical illusions • The stick in water isn’t bent n Atmospheric effects • Mirages as they appear; Stars don’t twinkle n Time lapse illusions • Some stars no longer exist n Radical philosophical doubt • Descartes’ Demon; Plato’s Cave; The Matrix; Brain in a Jar

Illusions of perspective

Illusions of perspective

Light refraction

Light refraction

Objects on the horizon

Objects on the horizon

Railway tracks

Railway tracks

Very small objects n Can you guess what this is?

Very small objects n Can you guess what this is?

Belief, Knowledge & Certainty n Belief • A proposition that is held to be

Belief, Knowledge & Certainty n Belief • A proposition that is held to be true but without evidence n Knowledge • A proposition that is believed, is true and can be supported by evidence n Certainty • A proposition where there is no doubt about its truth

Question 2 What is knowledge?

Question 2 What is knowledge?

‘Knowing how’ v ‘knowing that’ n A distinction associated with Gilbert Ryle (1900 -1976)

‘Knowing how’ v ‘knowing that’ n A distinction associated with Gilbert Ryle (1900 -1976) n Knowing that • Facts and information; propositional knowledge; “I know that Berlin is in Germany” n Knowing how • An ability or skill; a dispositional or operational knowledge; “I know how to bake bread” n n Most of epistemology has been concerned with knowing that, especially classical debates Can all cases of ‘knowing how’ be reduced to collections of ‘knowing that’? • E. g. Knowing how to drive a car n n Is knowing that useless without knowing how? Is innatism only tenable as applied to knowing how?

The Tripartite Theory of knowledge n n A classical definition of knowledge An agent

The Tripartite Theory of knowledge n n A classical definition of knowledge An agent (A) can be said to know a proposition (P) if: n n n P is true (the truth condition) A believes P (the belief condition) A has sufficient evidence for P (the evidence condition This definition of knowledge is called “Justified true belief” Having two of these conditions is not enough to count as knowledge.

The Hesitant Student n n Teacher: Billy, what is 3 x 7? Billy: Er…(guesses)

The Hesitant Student n n Teacher: Billy, what is 3 x 7? Billy: Er…(guesses) is it 21? n n In this case p is true (3 x 7 is 21) and Billy has evidence for p (he has been to the classes) but he doesn’t believe P. Is this a case of knowledge?

The Lucky Punter n A gambler finds a four leaf clover so bets on

The Lucky Punter n A gambler finds a four leaf clover so bets on a horse that day believing that his horse will win now that he has this lucky charm. The horse does win. n n In this case p is true (the horse did win) and the punter believed p (he sincerely thought the horse would win) but his evidence for this belief seems inadequate. Is this a case of knowledge?

Santa’s Visit n Many children believe in Santa Claus. They leave cookies out for

Santa’s Visit n Many children believe in Santa Claus. They leave cookies out for him that are eaten the next morning and as promised the presents arrive every Christmas day. Parents, shopkeepers and teachers all reinforce this belief. n n In this case the children believe P (they think Santa is real) and have evidence for believing P (teachers and parents confirm it) but P isn’t true Is this knowledge?

Problems with the tripartite theory n The Gettier Problem n n n Infinite regress

Problems with the tripartite theory n The Gettier Problem n n n Infinite regress argument n n Smith has applied for a job, but has a justified belief that "Jones will get the job". He also knows that "Jones has 10 coins in his pocket". Smith therefore concludes that "the man who will get the job has 10 coins in his pocket". In fact, Smith gets the job but, as it happens, also has 10 coins in his pocket. So his belief that "the man who will get the job has 10 coins in his pocket" was justified and true but isn’t knowledge. Every justification in turn requires justification and arguably this demand for justification is never stated. Some justifications are unreliable n n n Sense experience is prone to deception Innate ideas are controversial Analytic truths are trivially true

Question 3 Can knowledge claims be justified?

Question 3 Can knowledge claims be justified?

Rationalism and Empiricism n Rationalism n n n n Reason is the source of

Rationalism and Empiricism n Rationalism n n n n Reason is the source of all knowledge Mind contains innate ideas Maths is a model for knowledge Knowledge can be gained a priori Knowledge can be certain The senses are easily fooled Examples: Plato, Augustine; Descartes; Leibniz n Empiricism n n n n The senses are the source of all knowledge Mind is a ‘tabula rasa’ Biology is a model for knowledge Knowledge is only gained a posteriori Knowledge can only ever be probable Reason only gives us access to uninformative tautologies Examples: Aristotle (? ) Locke; Berkeley; Hume

Section 2 Classic Texts in Epistemology

Section 2 Classic Texts in Epistemology

Outcomes 2 & 3 n Critically analyse a standard philosophical position in the area

Outcomes 2 & 3 n Critically analyse a standard philosophical position in the area of epistemology: n n Describe the epistemology of Descartes or Hume Explain the reasoning and assumptions on which this account is based Cite specific extracts Critically evaluate a standard philosophical position in the area of epistemology: n n n Explain the strengths and weaknesses of Descartes or Hume Present a conclusion on the persuasiveness of this account Give reasons in support of this conclusion

Section 2: Option 1 René Descartes

Section 2: Option 1 René Descartes

René Descartes Meditations on First Philosophy

René Descartes Meditations on First Philosophy

Historical Context n n n n The Renaissance The end of Scholasticism Rebirth in

Historical Context n n n n The Renaissance The end of Scholasticism Rebirth in knowledge Flourishing in the arts Architecture Painting Science

Historical Context n The Reformation n n Split in the church Birth of Protestantism

Historical Context n The Reformation n n Split in the church Birth of Protestantism Catholic dominance ends Europe divided Martin Luther

Historical Context n Discovery of the New World New cultures and peoples n New

Historical Context n Discovery of the New World New cultures and peoples n New world view n

René Descartes Meditation 1 The Sceptical Method

René Descartes Meditation 1 The Sceptical Method

Method n n n n n Assume nothing Start afresh Re-examine his beliefs Focus

Method n n n n n Assume nothing Start afresh Re-examine his beliefs Focus on foundational beliefs Reject obvious falsehoods But also reject even slightly doubtful beliefs Looking for 1 certainty to base his knowledge on Architectural metaphor Barrel of apples analogy

Attacking Sense Experience n n Objects in the distance Small objects Other arguments from

Attacking Sense Experience n n Objects in the distance Small objects Other arguments from illusion are possible But surely apart from these the senses are reliable?

Dreaming Argument n n A stronger argument against sense experience Any given sense experience

Dreaming Argument n n A stronger argument against sense experience Any given sense experience can be replicated in dreams Hence sense experience is unreliable In fact, there is never any sure way of distinguishing dreams from reality

A Priori truths n n n Dreams are like paintings They must be based

A Priori truths n n n Dreams are like paintings They must be based on reality Or at least the colours and shapes must be real Whether awake or asleep a square still has 4 sides Hence maths and geometry escape the dream argument and may be reliable

Do all dreams contain some knowledge?

Do all dreams contain some knowledge?

The Demon Hypothesis n n n An argument against a priori knowledge The ultimate

The Demon Hypothesis n n n An argument against a priori knowledge The ultimate in scepticism A test which any candidate for certainty must pass Imagine a demon were fooling us in everything we see and think If this scenario were true, could anything still be certain? This idea has reappeared in different forms

René Descartes Meditation 2 Finding Certainty

René Descartes Meditation 2 Finding Certainty

The Search for Certainty n n n Restates his sceptical approach Like Archimedes he

The Search for Certainty n n n Restates his sceptical approach Like Archimedes he is looking for 1 fixed point Assumes he has no body Assumes everything revealed by the senses is a lie Assumes the Demon fools him at every turn Can anything be known if we assume all this?

The Cogito n Cogito ergo sum n n n Defeats the Dreaming Argument n

The Cogito n Cogito ergo sum n n n Defeats the Dreaming Argument n n You must exist to be fooled A self-authenticating statement n n you must exist to dream Defeats the Demon Hypothesis n n I am, I exist (Meditations) I think therefore I am (Discourse) You affirm its truth each time you think it But surely we know external objects better than we know the mind?

The Wax Example n n n Wax has one set of properties when cold

The Wax Example n n n Wax has one set of properties when cold But all its properties change when heated Yet we still think it’s the same wax. Why? n n It can’t be the senses that tells us this - they give conflicting reports Can’t be imagination either - wax can change more ways than we can imagine So it must be pure mental scrutiny that reveals the true nature of the wax Hence Rationalism should be adopted over Empiricism

Perception n n In fact all perception is really a case of mental judgement

Perception n n In fact all perception is really a case of mental judgement We say we see a man crossing the square Yet all we see are a hat and cloak which could conceal an automaton Our judgements go beyond what we strictly have sense experience for

René Descartes Meditation 3 Rebuilding knowledge

René Descartes Meditation 3 Rebuilding knowledge

Rebuilding Knowledge n 1. 2. Descartes’ strategy in rebuilding knowledge rests on 2 central

Rebuilding Knowledge n 1. 2. Descartes’ strategy in rebuilding knowledge rests on 2 central claims: The clear and distinct rule The existence of a benevolent God

The Clear and Distinct Rule n What is it that convinces us of the

The Clear and Distinct Rule n What is it that convinces us of the truth of the Cogito? n n n It is a “clear and distinct” perception A psychological state which gives rise to irresistible certainty Hence anything else which is clear and distinct must also be certain This rule can now be used to rebuild knowledge by identifying other truths God’s existence, for example, can be known clearly and distinctly

The Trademark Argument n This argument in Meditation 3 helps support the clear and

The Trademark Argument n This argument in Meditation 3 helps support the clear and distinct rule n n n n We have an idea of God in our mind This idea must have a cause There must be as much reality in an effect as in its cause The cause of the idea is God The idea is like a trademark left in our minds by God The idea of God includes the notion that he is benevolent Hence God is no deceiver Hence whatever we perceive distinctly must be true since a benevolent God wouldn’t allow this level of deception

René Descartes Meditation 6 Resolution of Earlier Doubts

René Descartes Meditation 6 Resolution of Earlier Doubts

Naïve Realism n n n The simplistic view that unreflective people have External objects

Naïve Realism n n n The simplistic view that unreflective people have External objects present themselves to the senses unbidden They are more distinct than those presented by memory or imagination They can’t come from within so must come from without It seems that the sense come first and the intellect later So nothing is present to the mind that was not first present to the senses

Rejection of Naïve Realism n n n Descartes refers to arguments from Meditation 1

Rejection of Naïve Realism n n n Descartes refers to arguments from Meditation 1 Objects at a distance Phantom limbs n Demonstrate the fact that senses don’t always report the truth Dreaming argument n I don’t believe the objects in dreams are located outside of me so why make this assumption when awake? But must we resort to scepticism?

Rejection of Scepticism n n n Although we shouldn’t heedlessly accept sense reports, neither

Rejection of Scepticism n n n Although we shouldn’t heedlessly accept sense reports, neither should we heedlessly reject them We have a passive faculty for receiving ideas of objects but there must be an external cause to the ideas we receive These causes can only be: n n External objects God The demon God is not a deceiver so wouldn’t allow us to think that these ideas were caused by external objects when they weren’t

Sense Experience n n There is an outside world However it may not exist

Sense Experience n n There is an outside world However it may not exist in the way it is presented by my senses Everything I am taught by nature contains some truth God equips us with a number of faculties: n n Reason The Senses Memory It is impossible that there could be any falsity in my opinions which couldn’t be corrected by some faculty supplied by God

How is Error Possible? n Some things which my senses appear to be telling

How is Error Possible? n Some things which my senses appear to be telling me are in fact a misjudgement of reason n “Grass is green” • Grass stimulates sensations of green in us n “The tower is small” • The tower simply appears small and my memory and other senses can confirm its true size n “My amputated foot causes pain” • Feelings of pain from a distant body part could equally be caused by stimulating parts in between n With the judicial use of clear reasoning we can correct the errors of the senses

The Dream Argument n n n Dreams have no consistency between one dream and

The Dream Argument n n n Dreams have no consistency between one dream and the next. n Life picks up from where it left off but dreams do not The laws of nature are broken in dreams n People can fly or talk to dead people By the application of reason we can distinguish the two states when we are awake

The Demon Hypothesis If there were a demon, a benevolent God would not allow

The Demon Hypothesis If there were a demon, a benevolent God would not allow him to interfere with our perceptions n The hypothetical possibility of the demon is therefore no longer a threat n

Section 2 Option 2 David Hume

Section 2 Option 2 David Hume

David Hume Enquiry Concerning Human Understanding

David Hume Enquiry Concerning Human Understanding

Background n n n Empiricist Philosopher and Historian A pivotal figure of the Scottish

Background n n n Empiricist Philosopher and Historian A pivotal figure of the Scottish Enlightenment along with Adam Smith (1723 -1790) and Thomas Reid (1710 -1796) Key Works: n n n A Treatise of Human Nature (1740) An Enquiry Concerning Human Understanding (1748) Dialogues Concerning Natural Religion (1779)

Influences n Heavily influenced by John Locke (1632 -1704), Sir Isaac Newton (1642 –

Influences n Heavily influenced by John Locke (1632 -1704), Sir Isaac Newton (1642 – 1727) and Bishop George Berkeley (16851753). n Hume gets his notions of Empiricism, Representative Realism, and Scientific Method from them.

Hume’s Enquiry n n n Inspired by the empirical successes of Isaac Newton wants

Hume’s Enquiry n n n Inspired by the empirical successes of Isaac Newton wants to do the same for the human mind. He is undertaking a psychological study of man. Trying to uncover the fundamental principles of human reasoning. His method is one of empirical observation. Usually this involves introspection on his own thoughts and feelings.

Impressions and Ideas Idea of apple Impression of apple The Outside World?

Impressions and Ideas Idea of apple Impression of apple The Outside World?

Supporting Arguments n n n n It is impossible to have an idea without

Supporting Arguments n n n n It is impossible to have an idea without first having had a prior impression Hume challenges us to find counter examples Even God is just a complex idea Blind men can’t imagine colours Laplanders can’t imagine the taste of wine Selfish people can’t imagine generosity Some animals have additional senses hence can access additional ideas

Simple and Complex Ideas n n Impressions Golden Mountain Virtuous Horse God We do

Simple and Complex Ideas n n Impressions Golden Mountain Virtuous Horse God We do this by taking simple ideas and: n n n Simple Our imagination seems unlimited in its powers However all complex ideas must be based on on simple ideas we have previously copied from an impression n n Simple Ideas Augmenting Diminishing Transposing Compounding This supports the empiricist doctrine that “all ideas are ultimately based on sense experience”.

Critical Comment n Are all impressions more vivid than their ideas? n n Are

Critical Comment n Are all impressions more vivid than their ideas? n n Are all ideas more faint than their impressions? n n n E. g. Stripes Hume provides no ‘grammar’ to tell us how to link these ideas up. n n Ultraviolet; Infrared; gravity Can you ever conceive of simple ideas on their own without thinking of other ideas? n n Cocktail conversations Do all ideas have a prior impression? n n Nightmares or traumatic memories Is Hume’s account of perception too simplistic? n n Faint impressions when drunk; morning after embarrassment watch + pocket; zebra + crossing. Can we ever compare an impression with an idea in practice? (Barrier of Ideas) Can we ever compare impressions with the outside world? (Barrier of Impressions)

The Missing Shade of Blue n n n Hume’s own counter example! Imagine You

The Missing Shade of Blue n n n Hume’s own counter example! Imagine You had seen every shade of blue but one Then all shades of blue were arranged on a scale from darkest to lightest Hume asks if we could imagine the missing shade without a prior impression Hume surprisingly says yes but “…it’s so singular and obscure an example it should not alter our general maxim…”

Comments on the Missing Shade of Blue n The example is not “singular and

Comments on the Missing Shade of Blue n The example is not “singular and obscure”. n n Missing shade of red; missing note on a scale; missing type of architecture. If not based on impressions the idea must be innate! Threatens to undermine the whole of Empiricism! The example is not insuperable. n n n Hume could say that the missing shade is a complex idea based on simpler ideas. But doesn’t see the solution because he thinks colours must be simple ideas. Demonstrates Hume’s rather cavalier attitude.

The Association of Ideas n n n Why does the thought of one idea

The Association of Ideas n n n Why does the thought of one idea lead on to the thought of another? Ideas don’t come randomly they follow an order or pattern and are always related There are 3 principles of the association of ideas: n n Resemblance Contiguity (In time or space) Cause and Effect So every idea is always related to the next for one of these three reasons

Comments and Criticisms n n What is the difference between contiguity and cause and

Comments and Criticisms n n What is the difference between contiguity and cause and effect in Hume’s analysis? Is there really no such thing as a truly random chain of thought? n n n Is the subconscious mind available to us? n n What about people with “Butterfly Brains”? What about people with dementia or Tourettes’? (Freud) Seems incapable of proof or disproof. n Hume says that even if we can’t see the connection in people’s thought it will be apparent to them. n What if we ourselves are not even aware of the connection?

Hume’s Fork All Objects of Human Enquiry Relations of Ideas Matters of Fact “

Hume’s Fork All Objects of Human Enquiry Relations of Ideas Matters of Fact “ 3 x 5 = 1/2 x 30” Necessary; Analytic; A Priori Propositions “My cat has three legs” Contingent; Synthetic; A Posterior Propositions

Comments on Hume’s Fork n Hume confuses An epistemological distinction with a semantic distinction

Comments on Hume’s Fork n Hume confuses An epistemological distinction with a semantic distinction n A Priori Analytic A Posteriori Synthetic Kant claimed that there were synthetic a priori beliefs which tell us about the world but aren’t derived from experience n E. g. Every event has a cause. n n n Hume’s fork itself falls foul of the distinction. Is it a matter of fact or a relation of ideas? Hume can’t just say we should disregard all exceptions as nonsense. If he is right exceptions shouldn’t even occur. If they occur at all then his distinction is nonsense

Matters of Fact n Many knowledge claims concern unobserved matters of fact. n n

Matters of Fact n Many knowledge claims concern unobserved matters of fact. n n n n Statements about the future (Physics) Statements about the past (History) Statements about far away places (Geography) Even day to day knowledge claims The basis of all our reasoning concerning matters of fact is “cause and effect” But where does our idea of cause and effect come from? An analysis of causes reveal that they have three features: n n n Priority Contiguity Necessity

Causation n We all have an idea of necessary connection but where does this

Causation n We all have an idea of necessary connection but where does this idea come from? Is it a ‘matter of fact’ or is it a ‘relation of ideas’? Is it acquired by experience a posteriori? n n No. We have no impression of the ‘necessity’ or ‘power’ transferring between causes and their effects. Is it acquired a priori by reason? n No. It’s not true by definition that apples must fall to the ground. Causes don’t resemble effects so we can’t know a priori what the effects of any cause will be.

The Origin of our Belief in Causation n n n Hume provides a psychological

The Origin of our Belief in Causation n n n Hume provides a psychological justification for our belief in necessary connections Our belief in causes connection is based on ‘custom and habit’ We don’t observe necessary connections, we only actually observe ‘constant conjunctions’. But once we see them often enough we develop an expectation that the future will resemble the past. But this belief is actually irrational. It’s just a fact about human psychology that our brains work this way. It’s basis is simply “custom and habit”. The only reasoning here is the “reason of animals”.

Comments n n n Does Hume’s analysis of causation undermine the whole of science?

Comments n n n Does Hume’s analysis of causation undermine the whole of science? Does Hume’s analysis of causation undermine his whole project? Is Hume claiming that there is no difference between causation and correlation? n n Is temporal priority the only way to distinguish causes from their effects? n n E. g. Compulsive gamblers; Alcoholics; abusive partners? Do we need constant conjunction to infer causal connections? n n What about contemporaneous causes? Is Hume’s psychological account a sufficiently complex psychology? n n E. g. Tiredness and the 10 O’Clock News E. g. food poisoning or electrocution How significant is contiguity in leading us to infer causal connections?

Hume’s Scepticism n After rigorously applying his “fork”, Hume admits that his position is

Hume’s Scepticism n After rigorously applying his “fork”, Hume admits that his position is in many respects a sceptical one n The Outside World: n n God: n n Is neither true by definition nor observed. The self: n n Impressions come “unbidden into the mind…we know not from where”. There may be no world out there. We have no constant impression of a unified self. We are just a bundle of impressions. Moral Values: n These aren’t revealed by reason or experience. Just a fact of psychology that we approve of some acts and disapprove of others.

Comments on Hume’s Scepticism n A surprising outcome for an empiricist philosopher. n n

Comments on Hume’s Scepticism n A surprising outcome for an empiricist philosopher. n n n “Hume developed empiricism to its logical conclusion and more or less destroyed it by doing so” Richard Osborne Leaves us knowing not very much for certain. Descends into Solipsism Must we accept Representative Realism? Must we accept foundationalism?