Theory of Knowledge

Introduction You know a lot by now! Easy access to even more knowledge Newspapers!‘Alien base found on dark side of the moon’ - Internet!‘Elvis is alive’ websites Claims made about future all the time

‘There is no likelihood that humans will ever tap the power of the atom’ Robert Millikan, Nobel Prize winner in Physics ‘The atom bomb will never go off and I speak as an expert’ Admiral Leahy, advisor to the US President (1945) ‘I think there will be a world market for 5 computers’ Thomas Watson, founder of IBM (1958) ‘By 2000 women will wear pants, men will wear skirts, both sexes will go bare-chested and clothes will be see-through.’ Rudi Gernreitch. American fashion expert (1970) ‘The internet will never take off.’ Bill Gates, founder of Microsoft (1988) It isn t just stupid people who get things wrong! It could be that what you learn in school will not be totally correct How do you know if something is true?

Current estimates are that the universe is 15 billion years old - The earth is 4.55 billion years old Humans developed about 2 million years ago - These figures are controversial! – most probably wrong 12pm 1 January – and the universe began exactly 1 year ago 1 May – the galaxy formed 9 September – solar system Few days later the earth was formed (14th) 25 September – life begins 12 November – oldest photosynthetic plants develop 1 December – significant quantity of oxygen in the atmosphere For the first 8 ½ months there was no earth For another 2 ½ there was no conceivable way for humans to survive 19 December – fish developed – trees followed soon after (23rd) 24 Decemeber – dinosaurs, mammals 26th 28th December – seems a massive comet hit earth causing major climatic change killing dinosaurs 31 December – humans appeared – all human history happened on the last day of the year 11.59.59 – Renaissance and Industrial Revolution We (in this room) have existed for a tiny fraction of second, on the last day How likely is it that we have found out any profound truths about the universe?

What is knowledge? Many people see knowledge as organised common sense – some validity but often little more than vague & untested beliefs based on prejudice, hearsay and blind appeals to authority Common sense is a starting point in coping with the world Mental map of reality – our ideas of T & F, what is reasonable/ unreasonable, right/wrong However, you should be willing to subject your MM to critical scrutiny

Mercator Projection Distorts relative size – places further from Equator = larger. Africa 4x Greenland Northern Hemisphere at top – no up or down! Eurocentric – Pacific?

Hobo-Dyer projection – reflects relative sizes Disorientating! Illustrates grip habitual ways of thinking have on our minds – difficult to break Common sense mental maps may give us a distorted picture of reality Ideas & beliefs – own exp, parents, friends, teachers, books, media Can t check everything – MM - likely inaccuracies, half truths, falsehoods Customs & conventions – difficult to think outside what we are familiar with Cultural biases – Greatest writer? Greatest scientist? (GB = Shakespeare, Newton. Italy = Dante, Galileo) Can we have a perfect map? 1:1 – quickly out of date – to be useful it has to be imperfect ‘the map is not the territory

You have 5 minutes to write down things that you “know”. What do you know? You have 5 minutes to write down things that you “know”. If there are problems with our common sense picture should we stick to what we are certain about? If you know something you are certain it is true If you believe something you may think it is true, but you are not certain But, how certain can we ever be?

What is knowledge? Of the things you know, can you pick 3 things that you are certain of?

What is knowledge? Can you choose three of the things you “know” that you are least certain of?

Belief/knowledge continuum Unlikely Probable Impossible Possible Certain Expalin that your knowledge can be placed on this continuum. You could possibly get them to place their own “knowledge” on the line.

Where do we get our knowledge from? Look at your list of things that you „know”. Where and how did you get that knowledge? They can work on this in groups.

How do you know?

The sky is blue?

Perception Print his sheet out. Get them to count the leprechauns. Then cut the top half as shown and swap the top halfs – ONE MORE LEPRECHAUN! How?! How safe is our perception of truth?!

Perception

How many leprechauns?

Perception Tractor Perspective Illusion - Optical Illusion Image Gallery #33

1 + 1 = 2

1 + 1 = 2? In base 2, 1 + 1 = 10 104 103 102 101 100 10-1 10-2 10-3 1 5 25 24 23 22 21 20 2-1 2-2 2-3

1 + 1 = 2? + = One pile of sand + one pile of sand = one pile of sand

I know I went for a run yesterday Can you trust your memory? Have you seen the Matrix?!

I know women are more emotional than men Is this a knowledge statement?

I know I love my brother How?

I know that a lake is more beautiful than a sewage works How?

I know the room is hot How?

I know that Mozart was a great composer How?

I know there is life after death Could you?

I know there is a God Good one this!

I know dogs are disgusting

“certainty” I think, therefore I am Distinguishes knowledge from belief. Truth without doubt. Language Perception Reason Emotion I think, therefore I am 31

I know Santa Claus exists “relativism” No absolute objective truth Knowledge is relative to the individual, culture or society I knew the Earth was flat I know Santa Claus exists This may be safer for ethics, politics & religion. But what about maths and science? 32

“justified, true belief” you must believe the knowledge statement your belief in the knowledge statement has to be true your true belief has to be justified. 33

“justified, true belief” Requires: Evidence – reasonable & positive evidence that supports & justifies belief. Coherence – does this fit with our current understanding? Can you see any problems with these requirements? 34