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

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Presentation on theme: "An Epistemology Update John Rafferty MA MSc PGCE Senior Lecturer Social Sciences Langside College Glasgow Tel: 0141 272 3875."— Presentation transcript:

1 An Epistemology Update John Rafferty MA MSc PGCE Senior Lecturer Social Sciences Langside College Glasgow Tel:

2 Section 1 Philosophical Issues in Epistemology

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

4 Question 1 Why are knowledge claims a problem in philosophy?

5 Appearance and Reality Perceptual problems Colour blindness; hallucinations Optical illusions The stick in water isnt bent Atmospheric effects Mirages as they appear; Stars dont twinkle Time lapse illusions Some stars no longer exist Radical philosophical doubt Descartes Demon; Platos Cave; The Matrix; Brain in a Jar

6 Illusions of perspective

7 Light refraction

8 Objects on the horizon

9 Railway tracks

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

11 Question 2 What is knowledge?

12 Knowing how v knowing that A distinction associated with Gilbert Ryle ( ) Knowing that Facts and information; propositional knowledge; I know that Berlin is in Germany Knowing how An ability or skill; a dispositional or operational knowledge; I know how to bake bread 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 Is knowing that useless without knowing how? Is innatism only tenable as applied to knowing how?

13 The Tripartite Theory of knowledge A classical definition of knowledge An agent (A) can be said to know a proposition (P) if: 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.

14 The Hesitant Student Teacher: Billy, what is 3x7? Billy: Er…(guesses) is it 21? In this case p is true (3x7 is 21) and Billy has evidence for p (he has been to the classes) but he doesnt believe P. Is this a case of knowledge?

15 The Lucky Punter 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. 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?

16 Santas Visit 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. 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 isnt true Is this knowledge?

17 Problems with the tripartite theory The Gettier Problem 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 isnt knowledge. Infinite regress argument Every justification in turn requires justification and arguably this demand for justification is never sated. Some justifications are unreliable Sense experience is prone to deception Innate ideas are controversial Analytic truths are trivially true

18 Question 3 Can knowledge claims be justified?

19 Rationalism and Empiricism Rationalism 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 Empiricism 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

20 Section 2 Classic Texts in Epistemology

21 Outcomes 2 & 3 Critically analyse a standard philosophical position in the area of epistemology: 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: 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

22 Section 2: Option 1 René Descartes

23 Meditations on First Philosophy

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

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

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

27 René Descartes Meditation 1 The Sceptical Method

28 Method 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

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

30 Dreaming Argument 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

31 A Priori truths 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

32 Do all dreams contain some knowledge?

33 The Demon Hypothesis 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

34 René Descartes Meditation 2 Finding Certainty

35 The Search for Certainty 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?

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

37 Rationalism and Empiricism A major dispute running through the entire history of philosophy has to do with the source(s) of human knowledge. There are two major schools: rationalism and empiricism. The empiricists hold that knowledge is derived from sense perception and experience. The rationalists (such as Descartes) hold that knowledge is derived from clear logical thinking, from the intellect (i.e., from "reason").

38 The Wax Example Wax has one set of properties when cold But all its properties change when heated Yet we still think its the same wax. Why? It cant be the senses that tells us this - they give conflicting reports Cant 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

39 Perception 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

40 René Descartes Meditation 3 Rebuilding knowledge

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

42 The Clear and Distinct Rule What is it that convinces us of the truth of the Cogito? 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 Gods existence, for example, can be known clearly and distinctly

43 The Trademark Argument This argument in Meditation 3 helps support the clear and distinct rule We have an idea of God in our mind This idea must have a cause There must be as much reality in the cause as in its effect 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 wouldnt allow this level of deception

44 René Descartes Meditation 6 Resolution of Earlier Doubts

45 Naïve Realism 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 cant come from within so must come from without It seems that the sense comes first and the intellect later So nothing is present to the mind that was not first present to the senses

46 Rejection of Naïve Realism Descartes refers to arguments from Meditation 1 Objects at a distance Phantom limbs Demonstrate the fact that senses dont always report the truth Dreaming argument I dont believe the objects in dreams are located outside of me so why make this assumption when awake? But must we resort to scepticism?

47 Rejection of Scepticism Although we shouldnt 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: External objects God The demon God is not a deceiver so wouldnt allow us to think that these ideas were caused by external objects when they werent

48 Sense Experience 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: Reason The Senses Memory It is impossible that there could be any falsity in my opinions which couldnt be corrected by some faculty supplied by God

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

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

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

52 Section 2 Option 2 David Hume

53 Enquiry Concerning Human Understanding

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

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

56 Humes Enquiry 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.

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

58 Supporting Arguments 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 cant imagine colours Laplanders cant imagine the taste of wine Selfish people cant imagine generosity Some animals have additional senses hence can access additional ideas

59 Simple and Complex Ideas 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 Golden Mountain Virtuous Horse God We do this by taking simple ideas and: Augmenting Diminishing Transposing Compounding This supports the empiricist doctrine that all ideas are ultimately based on sense experience. Complex Ideas Simple Ideas Simple Impressions

60 Critical Comment Are all impressions more vivid than their ideas? Faint impressions when drunk; morning after embarrassment Are all ideas more faint than their impressions? Nightmares or traumatic memories Is Humes account of perception too simplistic? Cocktail conversations Do all ideas have a prior impression? Ultraviolet; Infrared; gravity Can you ever conceive of simple ideas on their own without thinking of other ideas? E.g. Stripes Hume provides no grammar to tell us how to link these ideas up. 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)

61 The Missing Shade of Blue Humes 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 …its so singular and obscure an example it should not alter our general maxim…

62 Comments on the Missing Shade of Blue The example is not singular and obscure. 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. Hume could say that the missing shade is a complex idea based on simpler ideas. But doesnt see the solution because he thinks colours must be simple ideas. Demonstrates Humes rather cavalier attitude.

63 The Association of Ideas Why does the thought of one idea lead on to the thought of another? Ideas dont come randomly they follow an order or pattern and are always related There are 3 principles of the association of ideas: Resemblance Contiguity (In time or space) Cause and Effect So every idea is always related to the next for one of these three reasons

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

65 Humes Fork All Objects of Human Enquiry Relations of Ideas 3 x 5 = 1/2 x 30 Necessary; Analytic; A Priori Propositions Matters of Fact My cat has three legs Contingent; Synthetic; A Posteriori Propositions

66 Comments on Humes Fork Hume confuses An epistemological distinction with a semantic distinction A Priori Analytic A Posteriori Synthetic Kant claimed that there were synthetic a priori beliefs which tell us about the world but arent derived from experience E.g. Every event has a cause. Humes fork itself falls foul of the distinction. Is it a matter of fact or a relation of ideas? Hume cant just say we should disregard all exceptions as nonsense. If he is right exceptions shouldnt even occur. If they occur at all then his distinction is nonsense

67 Matters of Fact Many knowledge claims concern unobserved matters of fact. 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: Priority Contiguity Necessity

68 Causation 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? No. We have no impression of the necessity or power transferring between causes and their effects. Is it acquired a priori by reason? No. Its not true by definition that apples must fall to the ground. Causes dont resemble effects so we cant know a priori what the effects of any cause will be.

69 The Origin of our Belief in Causation Hume provides a psychological justification for our belief in necessary connections Our belief in causes connection is based on custom and habit We dont 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. Its just a fact about human psychology that our brains work this way. Its basis is simply custom and habit. The only reasoning here is the reason of animals.


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

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

73 Comments on Humes Scepticism A surprising outcome for an empiricist philosopher. 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?

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