Introducing Epistemology Chapter 9 What do you see

Introducing Epistemology Chapter 9

What do you see? A box in a room or a notched box?

What do you see? Two faces or a vase?

What do you see? Which is longer?

What do you see? Good or evil?

What do you see?

What do you see? Count the black dots

What do you see? Which middle circle is bigger?

What is Epistemology? n Optical illusions and things like trompe l’oeil make people wonder whether the world perceived through their senses and comprehended by their minds is what it appears n Evidence presented to the senses and analyzed by the powers of reason are not necessarily reliable n people cannot always be certain of what they know or how they know things n e. g. : Zhuangzi

What is Epistemology? (con’t) n The essence of epistemology n “Epistemology” comes from the Greek episteme which means “knowledge” and the English suffix “ology” meaning the “study of” n Epistemology is the study of knowledge n What is knowledge? What does it mean to know?

Nature and Aims of Epistemology n Epistemological questions explore the nature of knowledge n Ask how someone has come to know something, inquire into the scope and limits of knowledge or try to discover the degree of certainty attached to particular knowledge n E. g. : the stick that appears to bend in the water n Use the knowledge of science to rationalize that the stick is not bent but it is the refraction of light in the water that makes it look that way n But the epistemologist might ask how do you really know that the stick does not actually bend in the water

Nature and Aims of Epistemology (con’t) n These questions explore the scope, nature, limits and origin of human knowledge and as a result every field of philosophy involves epistemological questions n Often considered one of the pillars of philosophy

The Philosopher’s Approach to Epistemology n Questions that look into the relation between knowledge and truth and the roles played by the senses and reason in acquiring knowledge probe the foundation of knowledge n e. g. : What is knowledge? Can people know the world as it really is? Are there some things that humans can never know? How can we claim to know anything and why? n Answers to these types of questions constitute a theory of knowledge or epistemology n This determines our conception of reality n Scientists and epistemologists approach issues differently n Scientists use methods of observation and experimentation n The epistemologist may question the evidence presented by the scientists’ senses

What Philosophers Have Said n Chinese philosopher Kongfuzi (Confucius) said about knowledge: “To realize that you know something when you do, and to realize that you do not when you do not – this then is knowledge. ” n Wise people do not claim to know more than they do

What Philosophers Have Said (con’t) n Plato n Believed that the things people perceive through the senses are subject to change because these things disintegrate, dissolve and wear down n Thus, this type of knowledge is unreliable because people can never generate more than an opinion about objects belonging to the sensory world § Only reason, undistracted by the senses and bodily needs can reveal genuine, true knowledge § Through reason one can understand the eternal, unchanging world of ideas he called forms § The forms are innate and the world of forms represents a non-material reality that is superior to humans’ earthly existence

What Philosophers Have Said (con’t) n Aristotle n Did not agree in Plato’s idea of knowledge of the world of forms as superior and maintained that knowledge came from experience n Experience was evidence through the senses § Believed that reason came into play after people experienced things through their senses

What Philosophers Have Said (con’t) n Descartes n n Not until Descartes however was epistemology a pivotal line of questioning in philosophy In developing his theories Descartes used a particular method: the method of doubt n First set aside all he thought as true and all previous beliefs about knowledge n Would trust not his senses or reason and only accept what he could know with absolute certainty n Used a method of systematic doubt to conclude that at least he knew he was thinking

What Philosophers Have Said (con’t) n Descartes even questioned the knowledge of his own existence when devising his counterarguments that questioned knowledge n E. g. : dream argument and the evil-genius argument n He concluded that even if there was something fooling him that at least he had to be there to be fooled and he existed as a thinking being n “Cogito ergo sum” or “I think, therefore I am. n Descartes believed that people could come to know things independently of physical reality by using the power of reason n He was a rationalist

What Philosophers Have Said (con’t) n Locke n n Challenged Descartes’ notion of rationalism Locke developed a rival school of epistemology that attacked Descartes’ theory of reason as a primary source of knowledge n He borrowed from Aristotle and said that the mind was tabula rasa at birth and it was experience that created ideas n He was an empiricist

What Philosophers Have Said (con’t) n Kant n The debate between the two sides waged on until Kant tried to reconcile the two ideas n Kant made consciousness a central feature in his philosophy n “unity of consciousness” § A person’s consciousness is unified in his/her mind and no one else’s n Knowledge be it the product of reason or the result of sense is bound together by the human mind § The process of unifying innate ideas and sense perception into a single consciousness is a mental activity that must take place before anything can be known

What Philosophers Have Said (con’t) n Now new schools of epistemology have emerged n n n Some argue that only logic, mathematics or science is reliable Others suggest that true knowledge is only knowledge upon with most people agree Still others argue that knowledge is relative and influenced by personal and cultural beliefs

How Philosophers Have Said It n Rationalists Believe that knowledge comes from exercising the human ability to reason n Reason not only enables people to know things that the senses do not reveal but it is also the primary source of knowledge § Plato and Descartes were rationalists n Empiricists n Believe that knowledge comes from experience n This is evidence provided by the senses n Though these schools of thought exist, very few philosophers will maintain that knowledge only comes from reason or experience n Disagreement is how much of it comes from where n

How Philosophers Have Said It (Con’t) n A priori knowledge n n n Knowledge that is gained before sense experience and does not depend on evidence as provided by the senses n Derived strictly from our mental ability to reason Rationalists emphasize the importance of a priori knowledge n E. g. : Plato’s theory of forms and innate ideas are a kind of a priori knowledge A priori knowledge is true and cannot be doubted n E. g. : mathematical ideas § Einstein used pure reason to develop his theory of relativity § The nature of black holes, the origins of the universe, dark matter

How Philosophers Have Said It (Con’t) n A posteriori knowledge n Depends on evidence provided by the senses n E. g. : you see a black swan and this experience changes your knowledge of swans

What is Knowledge? n Buddha defined knowledge as belief produced by a reliable means The question is: What is reliable means? n Rejected authority or reason as means of knowledge but rather through action and experience n

Opinions, Beliefs and Knowledge n Statements that express beliefs are considered somewhat more reliable than statements that express opinions because belief statements can be classified as true or false

Conditions for Knowledge True Belief n At least two conditions must be fulfilled before anyone can claim to have knowledge n Truth and belief n As a result knowledge is sometimes defined as true belief § Nonetheless this question has been questioned § e. g. : Plato’s Theaetetus n Bertrand Russell n Challenged the definition of knowledge as true belief n Knowledge cannot be true belief because it may be based on false belief

Conditions for Knowledge (con’t) Justified True Belief n Plato is often credited with suggesting that along with true belief one must have justification for the belief in order for it to be knowledge n justified true belief n Accordingly three conditions are necessary to claim knowledge n n n Truth Belief Justification

Conditions for Knowledge (con’t) n Gettier challenged this definition by suggesting that someone can have justified true belief that is false n Some philosophers add a fourth condition that takes Gettier’s problem into consideration n Justification cannot depend on a false statement