1. Epistemology, Part I Introduction to Philosophy Jason M. Chang

2. Introduction to epistemology Definition Three major questions of epistemology 1. What is knowledge? 2. How do we acquire knowledge? 3. To what extent can we have knowledge?

3. Question 1: What is knowledge?

4. Different types of knowledge The standard view Gettier challenge

5. What is knowledge? Smith has applied for a job, but, it is claimed, has a justified belief that “Jones will get the job” instead of him. He also has a justified belief that "Jones has 10 coins in his pocket". Smith therefore justifiably concludes that, “The man who will get the job has 10 coins in his pocket.” In fact, Jones does not get the job. Instead, Smith does. However, as it happens, Smith (unknowingly and by sheer chance) also had 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. Edmund Gettier (1927- )

6. Question 2: How do we acquire knowledge?

7. Background The debate To what extent do we depend on sensory experience to arrive at knowledge of the external world? The positions o Rationalism o Empiricism

8. Background Important vocabulary o Propositions o Ideas/concepts o A priori vs. a posteriori knowledge

9. Rationalism Definition Common beliefs among rationalists o Innate knowledge or concepts o A priori knowledge Plato (427-347 BC)Descartes (1596-1650) Spinoza (1632-1677) Leibniz (1646-1716)

10. Rationalism Plato’s argument in the Meno (P1) Arriving at answers (to a problem in math or philosophy) requires recognizing when the answer has been discovered. (P2) Humans could not recognize when they have found the answer (to a problem in math or philosophy) if they were born with no knowledge whatsoever. (P3) Yet, humans can recognize when they have found the answer (to a problem in math or philosophy) Therefore, (C) Humans must have been born with some knowledge.

11. Rationalism Never experienced perfection argument (Descartes) (P1) We have never experienced in a circle, triangle, God, etc. in their fullness and perfection. (P2) Yet we still have a concept of a circle, triangle, God, etc. Therefore, (C) Our concepts of circle, triangle, God, etc. must be innate.

12. Rationalism Leibniz’s necessary truths argument (P1) We recognize that some truths such as the Pythagorean theorem are necessary truths. (P2) It is impossible for experiences, regardless of how numerous they may be, to establish the universal necessity of a necessary truth (e.g., Pythagorean theorem) Therefore, (C) Experience cannot be the source of our knowledge of necessary truths (e.g., Pythagorean theorem).

13. Empiricism Definition Common beliefs among empiricists o A posteriori knowledge o Mind as a blank slate (tabula rasa) at birth Locke (1632-1704)Berkeley (1685-1753) Hume (1711-1776)

14. Empiricism John Locke’s famous tabula rasa “Let us then suppose the mind to be, as we may say, white paper, void of all characters, without any ideas: - How comes it be furnished? […] To this I answer, in one word, from experience. In that all our knowledge is founded: and from that it ultimately derives itself.” John Locke (1632-1704)

15. Empiricism Locke’s first argument against innate ideas Locke’s assumption o If knowledge is innate, there would be universally accepted beliefs o The question Are there beliefs that enjoy universal acceptance?

16. Empiricism Locke’s first argument against innate ideas (P1) If knowledge is innate, there would be universally accepted truths. (P2) There are no beliefs that are universally accepted. Therefore, (C) Knowledge is not innate.

17. Empiricism Locke’s second argument against innate ideas Can a person born blind and deaf have concepts of color? Sound? Shape? Mathematics? Helen Keller (1880-1968) Note: Keller was not born deaf and blind, but was inflicted by deafness and blindness before the age of 2.

18. Empiricism Locke’s second argument against innate ideas (P1) If knowledge is innate, a child kept in isolation would still have ideas of specific colors, sounds, shapes, etc. (P2) It is obvious that such a child would not have any concepts of these ideas. Therefore, (C) Knowledge is not innate.

19. Empiricism John Locke on acquiring knowledge “[A]ll born into the world, being surrounded with bodies that perpetually and diversely affect them, variety of ideas […] are imprinted on the minds of children. Light and colors are busy at hand everywhere; sounds and some tangible qualities fail not to solicit their proper senses and force and entrance into the mind.” John Locke (1632-1704)