Understanding Knowledge Claims: Epistemology's Challenges, Justifications, and Responses

1. Epistemology Section 1 • What is knowledge? • Why are knowledge claims a problem in Philosophy? • Can knowledge claims be justified?

2. Epistemology Section 1 • What is knowledge? • The distinction between knowing ‘how’ and knowing ‘that’. • Tripartite theory (justified, true, belief) • The difference between knowledge, belief and certainty

3. Epistemology Section 1 • Why are knowledge claims a problem in Philosophy? • The difference between appearance and reality (Plato’s simile of the cave’ / Matrix) • Problems with the Tripartite theory • Accidental correctness (Gettier) • The problem of justification (challenge of scepticism) • Infinite regress of justification • Unreliability of the senses • Limitations of reason

4. Epistemology Section 1 • Can knowledge claims be justified? (Responses to scepticism) • Rationalism (e.g. Descartes, Plato) • Innate ideas • Senses are unreliable • Self-evident truths can be grasped by the mind without reference to the senses • Reason is the most reliable source of knowledge about the world

5. Epistemology Section 1 • Can knowledge claims be justified? (Responses to scepticism) • Problems with rationalism … • Can only give us indirect knowledge about concepts • A priori truths tell us nothing important about the world • Problems with innate ideas

6. Epistemology Section 1 • Can knowledge claims be justified? (Responses to scepticism) • Empiricism (e.g. Hume, Aristotle) • The mind as tabula rasa • Experience as the source of all ideas (concepts) • Reason can only give logical connections between ideas not knowledge about the world • Only experience gives us knowledge about the world.

7. Epistemology Section 1 • Can knowledge claims be justified? (Responses to scepticism) • Problems with Empiricism • The difference between appearance and reality • How do we do that our mental representation correspond to reality? • How can we deal with the problem of radical doubt?

8. Epistemology Section 2 • Option A: Descartes’ Rationalism Or • Option B: Hume’s Empiricism

9. Descartes’ Rationalism • Searching for a reliable foundation for knowledge • Reason as the foundation of knowledge: • Refuting sceptical arguments:

10. Descartes’ Rationalism • Searching for a reliable foundation for knowledge. • Aim of the Meditations … • How is Descartes going to achieve his aim? (Sceptical Method) • Authorities as a foundation of knowledge? • A posteriori truths as a foundation of knowledge? • A priori truths as a foundation of knowledge?

11. Descartes’ Rationalism • Searching for a reliable foundation for knowledge. • A posteriori truths as a foundation of knowledge? • Mistrust of the senses Med. I • Failed me in the past … • Perceptual illusions … • Maybe I’m mad? • The Dream argument Med. I • Hypothetical possibility • Extreme argument against a posteriori knowledge • Maths / external world survive

12. Descartes’ Rationalism • Searching for a reliable foundation for knowledge. • A priori truths as a foundation of knowledge? • The Evil Genius argument Med. I • Hypothetical possibility • Extreme argument against a priori knowledge • Makes sure he avoids slipping back into old habits • Allows him to ‘turn his will in the opposite direction’ • If anything survives this he can truly say that he has found certainty • Everything is lost …

13. Descartes’ Rationalism 2. Reason as the foundation of knowledge: • The Cogito Med. II • Non-analytical self-evident truth • It’s a self-authenticating statement (true every time it is conceived by the mind) • It’s self-contradictory to say “I don’t exist” • Survives even the demon argument • ‘Thinking’ survives whereas nothing based on sense experience does • Opens the way to his mind/body dualism • It is the one indubitable certainty that can act as a foundation for all others.

14. Descartes’ Rationalism 2. Reason as the foundation of knowledge: • God as the guarantor of clear and distinct perceptions Med. III • Clear and distinct perception / rule • Trademark argument for God’s existence • The idea of God includes the notion that he is benevolent • If God is good he would not deceive us • Clear and distinct perceptions must be true since a good God wouldn’t allow this level of deception

15. Descartes’ Rationalism 3. Refuting sceptical arguments: Med. VI • God is no deceiver therefore material reality exists • Errors in sense perception can be recognised and corrected • Refuting the dream argument

16. Descartes’ Rationalism 3. Refuting sceptical arguments: • God is no deceiver therefore material reality exists Med. VI • Strategy relies on clear and distinct rule / proof that God exists and is good. • Physical objects: • are not subject to Descartes’ will • are extended whereas the mind is unextended • These objects can’t originate, therefore, in the imagination … • Where then do they come from?

17. Descartes’ Rationalism 3. Refuting sceptical arguments: • God is no deceiver therefore material reality exists Med. VI • We passively receive ideas of outside objects, so there must be an external cause to the ideas. • The only possible cause of these ideas are the external objects themselves, or God, or the demon. • God exists and is good, therefore, he wouldn’t allow us to think these ideas were caused by external objects unless they actually existed

18. Descartes’ Rationalism 3. Refuting sceptical arguments: • Errors in sense perception can be recognised and corrected Med. VI • Strategy relies on clear and distinct rule / proof that God exists and is good. • Difference between the imagination and the intellect • Imagine a chiliagon • Use the intellect to understand a chiliagon • Imagination and the intellect are distinct faculties of the mind • Imagination deals with images of material things • Intellect deals with a priori truths

19. Descartes’ Rationalism 3. Refuting sceptical arguments: • Errors in sense perception can be recognised and corrected Med. VI • There is an outside world but is it like that reported by my senses? • Primary / Secondary qualities • Secondary (apparent) qualities (colour, smell, taste) • Originate in sensation • Subject matter of the imagination • Obscure and confused perception (prone to error) • Do not exist in the object (appear only in the perceiving mind) • Primary (or real) qualities (shape, position, size, number) • Subject matter of mathematics • Understood in the intellect • Perceived clearly and distinctly • Exist in the objects (inherent features of matter itself)

20. Descartes’ Rationalism 3. Refuting sceptical arguments: • Errors in sense perception can be recognised and corrected Med. VI • For example • ‘Grass is green’, we should say ‘Grass stimulates sensations of green in us’ • ‘The tower is small’ – we should say ‘the tower simply appears small and my memory and other faculties can confirm its true size’. • God equips us with various faculties: Reason, the senses, memory. • I now see it is ‘…impossible that there could be any falsity in my opinions which couldn’t be corrected by some faculty supplied by God’. • Some things which my senses appear to be telling me are in fact a misjudgement of reason • However, with a careful use of clear reasoning we can correct the errors in sense perception.

21. Descartes’ Rationalism 3. Refuting sceptical arguments: • Refuting the dream argument Med. VI

22. Problems with Descartes’ Rationalism • Problems with the sceptical method … • Problems with the cogito … • Descartes’ arguments rely on a good God • Descartes’ appeal to the clear and distinct rule • What might seem clear and distinct might not be true at all • Logical error … • Cartesian circle …