Epistemology

Rationalism and empiricism: Key terms

Today’s lesson

You will learn the meaning of various key terms related to rationalism and empiricism

Key things today

Some important key terms: A priori / a posteriori

Analytic / synthetic

Necessary / contingent

Rationalism / Empiricism

Philosophers debate whether our knowledge ultimately comes from reason or experience.

Consider the following statements. Are they based on reason or experience? How would we find out whether or not they are true?

1)Fred is tall2)2 + 2 = 43)A bachelor is an unmarried man4)If Fred is taller than Sam and James is taller

than Fred then James is taller than Sam.5)More people live in London than Nottingham.6)Human beings cannot fly without machines.

Reason and Experience

Booklets, p.39

Empiricism and Rationalism Empiricism

An empiricist believes that knowledge comes from our sensory experience of this physical world

E.g. I know the fire is hot because when I put my hand into the fire it burns

Rationalism A rationalist believes that knowledge

comes from the correct use of reason. Our senses can deceive us but if we

come to a rational conclusion it will not let us down

Philosophical views

Hume argued that all ideas come from sense impressions

Locke argued that experience was the source of all knowledge and at birth the mind was a tabula rasa

Plato argued that all knowledge about the world is a priori and innate

Descartes argued that the foundation of knowledge is the knowledge of one’s own mind: ‘I think therefore I am’

Leibniz argued that innate ideas are recovered through experience

Task - 20 minutes

Fill in the grid, making sure you come up with

strengths and weaknesses

Booklets, p.40-41

A priori or a posteriori?

75+4 = 79 Fred is 75 years old My Dad’s new car is red All bachelors are unmarried men If Fred is taller than Anne then Anne

is shorter than Fred Water boils at 100 degrees Celsius

Concepts and knowledge

In this unit, we will discuss whether all concepts and knowledge come from experience.

But what is a concept and how is it different from knowledge?

There is no philosophically neutral way of defining ‘concept’ because different philosophers use the term differently.

However, it isn’t just an alternative word for ‘idea’ or ‘theory.’

Ideas are things in the mind, but concepts are things we all share.

Booklets, p.39

Concepts and knowledge

Concepts are components of understanding. To have a concept of X (e.g. a house, an elephant, snow, etc) is to be able to recognise X-things as such and to be able to distinguish them from other things.

So if you can recognise a house when you see one, realise it is for living in and distinguish it from a flat or a hotel, then you can be said to have a concept of house.

Things are said to fall under concepts. The dwelling in which I live falls under the concept of house. Concepts can be of concrete things (mental and physical items) or abstract things (the number three).

Booklets, p.39

Discussion

So how do you think concepts are different from knowledge?

Video

Is reason the source of knowledge? Make notes on the following:▪ Descartes

▪ Leibniz

▪ Plato

▪ Geometry

▪ The continuing debate over whether the mind alone can generate knowledge