Chapter 5 :Epistemology


How do we know what we claim to know?     How do we find out what we know?  How do we judge claims to know? These are questions covered in this chapter.  They are in the field of Philosophy known as epistemology.

The ISSUES for epistemology are all in one way or another related to knowledge:: 







The sections of this chapter  will cover the following:

Theories of Knowledge





  • 5.SCIENCE   

Theories of Truth

  1.  CORRESPONDENCE THEORY               l

  2.  COHERENCE THEORY        



The following sections will look into these matters and attempt to answer some of these questions.

Those who think about knowledge realize that there are several basic types of knowledge.

The first kind might be thought of as Personal Knowledge or knowledge by acquaintance.  This is the sort of knowledge that people claim when they express claims such as "I know John Doe. "  Or "I know that building"

People also claim to know how to do things.  People claim to ahve the skill or experience to do things such as speak or drive or bake a cake or many other things. This is sometimes described as Prodecural Knowledge.

What philosophers are mainly concerned with are a third sort of knowledge where people claim to know things.  Those sorts of claims are often thought to be about "facts". This form of knowledge is termed Propositional Knowledge.  This will be the concern of this chapter.

Before we look into the various theories about how we know what we do know when we make propositional claims and how to determine if claims are true or not it would be helpful to make a number of important points or distinctions about language and how we use it.  Not all uses of language involve a claim that can be described as claims of knowledge.  There are a variety of forms of expressions or sentences in any language.  Not all sentences are functioning for the speaker in the same way. 

VIEW: Types of Claims 

Here are four of the different uses for language:

Expressive (Thus use includes sentences that are neither true nor false.)

"Holy Cow!"  "ouch" "Hurray!"

They express the feelings of the speaker/writer.

Directive (Thus use includes sentences that are neither true nor false.)

  1. "Please close the door."  

  2. "What time is it?"

  3. "How much does that cost?"

This use offers instructions or requests information.

Performative  (Thus use includes sentences that are neither true nor false.)

  1. "I bid five dollars."

  2. "I promise that I will do that."

  3. "I now pronounce you ..."

This use actually performs some operation.  It presents no information and makes no requests.

Evaluative (Thus use includes sentences that are neither true nor false.)

  1. "That is a good car."

  2. "She is a good person."

  3. Chocolate is the best flavor for ice cream.

This use expresses how people think about some object, activity, person, condition, or situation.  As the standard for making such evaluations is not such as to be derived from a source that is recognized as existing apart from humans and uninfluenced by culture there is no commonly agreed upon method for determining if such evaluations are true or not true.

Sentences expressing evaluations are not taken as making claims about what is known so much as making claims about how the evaluator thinks.

Cognitive (This use includes sentences that are either true or false, or potentially true or false.)

1.         There are three sides to a triangle.  The sum of their angles is 180 degrees.

2.         There is a computer in front of you right now.

3.         23 + 11= 34

4.         A bachelor is an unmarried male.

5.         If a is more than b, and b is more than c, then a is more than c.

6.         There are 1.8376 x 10 73rd grains of sand on planet Earth.

It is the cognitive use of language that concerns us with the issue of knowledge.  This is the use involved with Propositional Knowledge. It is the cognitive use that makes claims that should be capable of being determined to be either true or false.  Cognitive use of language expressing that which is claimed as knowledge exists in a variety of forms: logical, semantic, systemic and empirical. We will examine them in a subsequent section.  What they have in common is that claims are made that can be determined to be true or false in some manner or other.

For the remainder of this chapter it should be understood that it is the cognitive use of language that is of concern in so far as the issues of knowledge or truth.

For a look into What is knowledge?

READ: Dallas Roark How Do We Know?   What do we know  

VIEW: Jan Willem Lindemans  Epistemology or the theory of knowledge 

On Knowledge:




Proceed to the next section .

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