Epistemology – The Theory of Knowledge
By the end of this unit you should be able to
Explain propositional knowledge
Explain tripartite definition
Discuss the problems with this definition
Explain the part justification plays in knowledge claims
Explain and discuss empiricism and rationalism
Explain, analyse and evaluate Descartes’ epistemological claims
Epistemology is also called the theory of knowledge.
You may have heard people say “I know what I know okay!” This suggests that there is something certain that they possess which they call knowledge.
What is knowledge?
Here are some different knowledge statements.
I know the earth is the third planet from the sun.
I know how to ride a bike.
I know North Berwick.
I know 2 + 2 = 4
I know men.
I know all bachelors are unmarried men.
I know the sun will rise tomorrow.
I know food will nourish me.
I know salt tastes salty.
I know the best way home
I know murder is wrong
I know this is my body.
I know how to speak English.
I know what red is like.
I know the meaning of life
I know me.
I know I like ice-cream.
I know the earth is flat.
I know smoking is bad.
I know maths.
The list of different knowledge statements on this page can be grouped according to three basic types. This can be seen in examples 1-3.
1 I know the earth is the third plant from the sun = Knowledge that…
2 I know how to ride a bike = Knowledge how…
3 I know North Berwick = Knowledge about…
Knowing that.. is called propositional knowledge. Knowing that the earth is the third planet is an example of “knowledge that…”. Propositional Knowledge.
Knowing how to ride a bike is “knowledge how..”. This is an ability or a skill not propositional knowledge.
Knowing about North Berwick is a third kind of knowledge often called knowledge by acquaintance. It comes from familiarity. Implicit in this claim is that the claimant has been to North Berwick.
What about the statement “I know the quickest way to the school lunch hall”? What kind of knowledge claim is being made here? Why?
Some would claim that knowing how is a special kind of knowing that.
Epistemology is sometimes called the theory of knowledge. Epistemology is mainly concerned with the kind of knowledge involved in truth-claims, that is, when the truth or falsity of something is proposed or claimed. In other words propositional knowledge. Propositional knowledge is knowledge that, not knowledge how or knowledge about.
We are dealing with knowledge that something is the case – facts.
Knowledge that = propositional knowledge.
Definition of Propositional Knowledge
Perhaps the most common simple definition of knowledge is justified true belief. This important definition is also known as the tripartite definition of knowledge.
Tripartite Definition – “I have knowledge if…”
I believe that something is true
I have a good reason to believe that it is true and
It is true.
What this definition is claiming is that there are three necessary and sufficient conditions for knowledge to take place.
So for the first statement on page 1 to be knowledge an individual..
1 would have to believe that the earth was the third planet from the sun.
2 would have to have justification for believing that the earth was the third planet from the sun.
3 it would have to be true that the earth was the third plant from the sun.
What is epistemology?
What different kinds of knowledge are there?
Give examples of each.
With which kind of knowledge are we concerned?
How can this kind of knowledge be defined?
What does this definition claim?
Apply this definition to a propositional claim of your choice.
With what kind of knowledge are we not concerned? Give examples.
Into which of the three knowledge categories do each of the statements on page 1, examples 4-20 fall?
How would you respond to the claim “I know what I know”?
Obviously, the kind of knowledge involved in a straightforward historical claim like "I know that in fourteen hundred and ninety-two Columbus sailed the ocean blue" is quite different from the kind of knowledge delivered through an introspective intuition, as in "I know that I exist." And both of these are quite different from the knowledge involved in the religious assertion, "I know that God loves me" and so on.
Is Justified True Belief Knowledge?
Remember our working definition for knowledge is belief which is justified and true.
The question is - are these the only necessary and sufficient conditions for knowledge?
Some do not think so!
The Greek philosopher Plato pointed out that we can be right about something but not really know about something. He used a story to illustrate his argument.
A traveller asked a local which of the two roads ahead led to the town he wished to reach. The local, not knowing but wishing to be helpful pointed to the one which subsequently proved to be the right choice.
The traveller believed that it was the correct road, he was justified in his belief and his belief was true - it was the correct road - but he did really know it was the correct road?
Why do you think that Plato said that the traveller did not really know?