Sources of Knowledge: The origin of concepts and the nature of knowledge

1. Sources of Knowledge: The origin of concepts and the nature of knowledge • Outcomes: • to understand the key claims made by the different schools of epistemology about the sources of knowledge • to have begun considering how the validity of these claims • Warm-up: • List five things you know • How do you know these things? What is the source of this knowledge? • Is there anything in common between these sources? Are there any ultimate sources of knowledge

3. Empiricism Works with the evidence of the senses. Ultimate source of knowledge is sense experience.

4. Gnosticism: Works with evidence provided by God Ultimate source of knowledge is divine revelation

5. Rationalism: Works with evidence provided by rational thought – logic alone Ultimate source of knowledge is reason

6. Empiricism the information our senses give us is the ultimate source of all knowledge – reason works with this data. Rationalism - reason alone is the ultimate basis of all knowledge – sense-data only extends what we already know.

7. Rationalism Socrates (469-399 BCE) & pupil & amanuensis Plato (428-348 BCE) Descartes (1596-1650 ) Gottfried von Leibniz (1646-1716) Spinoza (1632–1677)

8. Empiricism Aristotle (384-322 BCE), pupil of Plato John Locke (1632 –1704 ) Bertrand Russell (1872-1970 David Hume (1711-1776 ) George Berkeley (1685–1753 )

9. Rationalism & Empiricism Immanuel Kant (1724-1804)

10. Different meanings of ‘idea’: • a PROPOSITION: e.g. ‘He had the idea it would be fun to take a day off’ Or: • or CONCEPT: e.g. ‘yellow’

11. Innate ideas: • Definition 1 (Locke): An idea which is a proposition or concept which is part of the mind at birth (and we are conscious of it). • Definition 2 (Rationalist): An idea which gives us substantive a priori knowledge through rational intuition and demonstration. • Definition 3 (Nativist): An idea which is a proposition or concept, with which the subject has been born, rather than gaining it from experience.

12. John Locke: We are born without any ideas – our mind is a ‘blank slate’ (a tabula rasa) (Locke extract: p.106, sheet) • What reasons are there for agreeing with Locke? • ACTIVITY, p.108 • Do concepts such as a ‘human being’ come ready-formed? What are the simplest concepts possible?

13. Locke’s theory of concept formation: What sense impressions go towards making up your idea of a human being? Simple Impressions – flesh tones in different shapes, eye colours in eye shapes, shape of hair in a colour, etc. Complex impressions of a human being Complex Ideas – of a human being We must first acquire sense impressions to form concepts, and concepts to be able to think of propositions – e.g. ‘The cat sat on a mat’

14. Locke’s theory: • See diagram on page 108! Copy, replacing the examples with ones of your own. • Why do we need ‘concepts’ (ideas) as well as sense data? • How can we come up with or imagine ideas of things we’ve not experienced? • Are there any ideas you can think of which don’t come from sense-experience?

15. Both Locke and later David Hume argue that we develop concepts of which we do not have sense impressions by working with sense impressions and concepts we already have. (Hume extract, p.107) Hume argues that the following are operations which are used in forming complex ideas, including those of which we have had no experience: • Augmentation - enlarging • Diminishment - reducing in size • Compounding - bringing two entire things together • Transposing - taking an element from one thing and putting it together with another • Negating- excluding an element of something • Give an example of an idea of fantasy which these operations could produce. - Activity, p.110 – do Locke and Hume’s theory work for all our ideas?

16. Locke’s supporting arguments: • Nothing is thought universally – therefore it seems unlikely that we are born with innate concepts • Children and ‘idiots’ (Locke’s term) do not have complex concepts (e.g. mathematical) that are claimed to be innate by Rationalists. • Empiricism is the simplest explanation of our ideas. Hume’s supporting arguments: • A blind woman cannot have a concept of colour. • A mild man cannot have a concept of white-hot anger. • We cannot have ideas of something we have not (directly or indirectly) experienced.

17. Hume on knowledge: A wise man proportions his belief to the evidence. David Hume(An Enquiry Concerning Human Understanding, 1748) Belief is nothing but a more vivid, lively, forcible, firm, steady conception of an object, than what the imagination alone is ever able to attain. David Hume

18. Hume’s scepticism: - To know whether an idea is a genuine concept or not, we must trace back its genesis to the original sense impressions which have created it. - IF we cannot find such impressions, then the idea must be false – we have made an error in supposing it to exist. • We might, though, be able to trace an idea back to its constituent parts, and see why we have created the concept. • Can you think of any philosophically-significant concepts which we might have created through the operations that Hume describes?

19. Hume’s view of metaphysics: Abstract ideas are characteristically vague and faint; Abstract ideas need to be reduced to their constituent sense impressions to see if they are accurate; Without reference to experience, words/concepts are nonsense, because they signify no idea; Ideas that speculate about a reality beyond or behind our experience are ‘merely sophistry and illusion’

20. Metaphysics: “If we take in our hand any volume; of divinity or school metaphysics, for instance; let us ask, "Does it contain any abstract reasoning concerning quantity or number?" No. "Does it contain any experimental reasoning concerning matter of fact and existence?" No. Commit it then to the flames: for it can contain nothing but sophistry and illusion.” - Hume, Enquiry Concerning Human Understanding

21. What would Hume’s view of the following be? The idea that there is a God who is infinite, all-loving, all-powerful, etc. The idea that we exist through time as a ‘thinking thing’? (Descartes) The idea that certain ideas are necessarily true? And that certain things MUST happen? (e.g. the sun rising tomorrow) The idea that we can identify a priori the relationship between an event and its cause? (i.e. one thing definitely being the cause of another)

22. Identity and Selfhood: “What we call a mind is nothing but a heap or collection of different perceptions, united together by certain relations and supposed, though falsely, to be endowed with a perfect simplicity and identity.” David Hume(A Treatise of Human Nature, 1739-1740)

23. Necessity and Causation: “Upon the whole, necessity is something, that exists in the mind, not in objects; nor is it possible for us ever to form the most distant idea of it, consider'd as a quality in bodies. Either we have no idea of necessity, or necessity is nothing but that determination of thought to pass from cause to effects and effects to causes, according to their experienc'd union.” David Hume(A Treatise of Human Nature, 1739-1740)

24. Necessity and Causation: “That the sun will not rise tomorrow is no less intelligible a proposition, and implies no more contradiction, than the affirmation, that it will rise.” David Hume(An Enquiry Concerning Human Understanding, 1748)

25. Introducing Hume… • https://www.youtube.com/watch?v=r3QZ2Ko-FOg&feature=player_embedded • https://www.youtube.com/watch?v=dPlNsyXl-0c - scepticism • https://www.youtube.com/watch?v=-QpUrSn3cWU – Hume’s Fork

26. Logical Positivism: • 20th century philosophical movement inspired by Hume’s empiricism • Claimed that sentences are only meaningful (provide us with information) if they are susceptible to empirical proof, or can be logically proven. • What kind of statements would this view rule out as ‘meaningful’? (Think of the other side of your course!)

27. Criticisms of Hume: Departs too far from common sense, e.g. in arguing that the self does not exist - do we simply have to accept the self? Just what counts as a ‘simple’ idea? (p.115) Can Hume’s theory of complex ideas account for abstract nouns such as beauty, truth, knowledge? - Can you find a concept which doesn’t seem to derive from experiences? How could we imagine ideas – e.g. a previously unexperienced shade of blue – if Hume’s theory is correct?

28. What counts as a ‘simple’ idea? • Unicorn = horse, horn • What constitutes a horse? A horn? • What constitutes a mane, hide, tail, etc.? • What constitutes hair? • Etc……

29. Criticism 2: Do all simple ideas come from sense experience? • Hume asks us to imagine whether someone who has never seen a particular shade of blue could imagine such a shade. • Hume thinks it is plausible that they could. Does this undermine the Empiricist case?

30. Missing shade of blue… • The ‘missing shade’ could be a complex concept. • But then… all shades of blue would be complex shades – mixtures of light and dark with general concept. • How then is any shade derived from a simple concept? • How do we move from any particular shade of blue to the general concept? And back?!

31. Missing shade of blue… • But if we cannot form the missing shade, then we must have millions of different concepts of every colour. • Do we all have slightly different conceptions of blue, according to our experiences? • If I have not experienced a shade, then it is not part of my general concept of blue. But how then do I recognize a new shade as blue? • What about ultra-violet – we can form a concept of it, but this is not derived from sense experience.

32. Criticism 3: Concepts which don’t relate to sense impressions: • What sense impression is the concept of Spain based on? • What sense impression is the concept of justice based on? • What sense impression are the concepts of prepositions (e.g. being near/far/next to/on top of, etc.), or relations (e.g. sibling) based on? • Do such concepts need to be rooted in ‘pictures’ at all? Are they more issues of logic, or innate ideas about relationships?

33. Abstract concepts: • How do we account for the connections between concepts involved in, for example, justice? • How can we arrive at similar concepts despite very different experiences? • Relational concepts – e.g. ‘on’, ‘between’, ‘and’, ‘sibling’, etc.

34. Criticism 4: • Do some concepts have to exist in the mind before sense impressions can be properly experienced?

35. Condillac’s Statue • P.120-121 • Would not a statue, which had a blank slate for a mind, and which received all its information from external sources, only forming ideas from this, not be faced with a ‘blooming, buzzing confusion’ of sense data (William James), without some innate categories which enable us to process it all? • Modern analogy: a computer without software? • Kant on the tabula rasa: “Thoughts without content are empty; intuitions [impressions] without concepts are blind.” • Are there innate structures, or ideas, which guide our understanding of sense experience?

36. Rationalist criticisms: • Are innate ideas those ideas which come to us only when we have full use of reason? (not children, mentally disabled) • Could we have a disposition implanted by God to think in way which leads to a priori truths • Descartes: a priori reasoning, self-reflection, rational intuition. • Plat’s innatism: ‘remembering’ specific concepts

37. Rationalist criticisms: • Could experience trigger innate knowledge? (either DISPOSITIONAL (Descartes) or INNATIST (Plato)). Just as we have innate capacities which develop, why not also innate concepts and knowledge which also develop (could be genetically encoded - Carruthers)? • Leibniz: we are like a marble block which has ‘veins’ which guide the impressions a sculptor can make • Carruthers and Chomsky: language-use (p.123) - how can Chomsky’s theory be criticised?

38. Empiricist’s response: • A baby’s ‘knowing’ that it should suckle is simply know-how, not propositional knowledge – it doesn’t know anything about the objects it is trying to manipulate, but how to use them.

39. Homework: • Outline and explain the criticisms of Empiricist theories of concept acquisition. (9 marks)

40. Keywords: • Ideas: mental experiences (e.g., concept of ‘yellow’) • Concept: an abstract representation of something – either of a particular thing, or of a relation between things • Knowledge: a proposition about something (e.g. this screen is black, blue and white in colour) • A priori: knowledge known independently from experience (e.g. no object can be red and green all over at the same time) • A posteriori: knowledge known through experience – i.e. learned. • Deductive argument: an argument in which the truth of the premises will guarantee a true conclusion.

41. Innate ideas • Claim that some of our ideas are not learned, but innate • All our (propositional) knowledge is rooted in the logical relations between these ideas – i.e. in reason and how these ideas are applied to our sense experience • Different versions of the claim: e.g. ideas could be implanted by God, be memories from a different life, emerge from the way our minds work, be part of the way our brain has evolved.

42. Descartes: • Why does Descartes think that our knowledge must be rooted in ideas provided by reason alone, not by experience? • (Reading, p.373)

43. Descartes’ innate ideas: • What does Descartes think he can know for certain? • What arguments does Descartes use to prove that God exists?

44. Criticisms of Trademark Argument: 1) Does every event have an equal cause? • Evolution • Match lighting a bonfire • Whisper setting off an avalanche 2) Do we really have an idea of infinity? And if not, does this mean that Descartes’ trademark argument cannot get off the ground?

45. Criticisms of Trademark Argument (2): 3) The idea of God is incoherent: • Paradox of the Stone • If incoherent, what does this imply about its cause? 4) Idea of an all-powerful God is not universal: - Omnipotent deity emerges at a historical point

46. Descartes’ ‘trademark’ argument for God – criticisms, cont.: 5) Empiricist accounts of origin of idea of God: - Our idea of God isn’t innate (and certainly not simply produced by something as powerful as God), but a sum of our experiences and our ability to think of them negatively (e.g. not finite = infinite) (Hume!)

47. Descartes’ ‘clear and distinct ideas’ about external world: • Descartes’ example: wax • Intuited by the mind, by ‘light of reason’ • Known by reason alone, therefore objective (available to all) – ‘primary qualities’ • E.g. basic claims of logic, geometry, mathematics • Cannot be doubted – all self-evident • Qualities such as smell, colour, feel, etc. are subjective (dependent on the observer) – ‘secondary qualities’

48. Other arguments for innate ideas: (Note distinction between innate instinct – know-how - and innate idea/concept – knowing that) • Morality – God-given? Intuitive? Rational? • Numbers – mathematical relationships • Beauty, justice, universal concepts

49. Chomsky on language • Modern philosophers have recognised the power of language to form the world we experience. • Noam Chomsky claims that we have ‘rules’ for language-use ‘hard-wired’ into our minds – a version of the thesis of innate ideas. • https://www.youtube.com/watch?v=xfiHd6DyuTUhttps://www.youtube.com/watch?v=7Cgpfw4z8cw • https://www.youtube.com/watch?v=xfiHd6DyuTU

50. Criticisms of innate ideas: Locke: 1) Theory of innate ideas is unnecessary – empiricism can explain where all our ideas come from (employs Occam’s Razor) (p.137) E.g. why would God provide us with eyes to see colour if we already had an innate idea of it? - However, does this account for all possible ‘innate’ ideas? 2) No ideas are universally held, therefore none is innate. • activity, p139 • E.g. Children and the mentally impaired do not have knowledge of even logically necessary truths. • However, does this necessarily negate possibility of innate ideas?