George Berkeley - Philosophy Knowledge and Perception
George Berkeley (1685-1753)
An Anglo-Irish philosopher (pictured right) famous for emphasizing the importance of
The city of Berkeley, California, was named after him.
His most famous book is...
A Treatise Concerning the Principles of Human Knowledge (1710)
What did he say about knowledge and perception?
1. Knowledge is experience
Like the English philosopher, John
Locke (pictured right), Berkeley believed that the main source of knowledge is
So they are both called empiricists.
2. “Immaterialist idealism”
This is what he called his belief that the world is made up of only one substance -
mind or thought .
This leads to the vital importance of perception (see point 3).
3. “To be is to be perceived” (esse est
percipi in Latin)
Because the world totally consists of mind or thought, what we experience is
Berkeley called such perceptions “ideas” , although he used the
term “spirit”, to describe spiritual
matters that are discovered through reflection and obedience to God.
This spirit can lead to
- passive inaction (when spiritual things are perceived), or
- positive results from willing things to happen (see point 4).
4. The importance of the will
Things are caused by willing them to happen through “volition” (or acts of
So success is dependent on self-discipline and determination to
turn your thoughts into positive action.
5. God is great
Berkeley was a devout Christian and believed that all our perceptions and experiences come from
Key quote on influencing people
To be is to be perceived