1. He argued that the objects of sensation, our sense-data, must depend on us in the sense that if we
stopped hearing or tasting or seeing or perceiving, then the sense-data could not continue to exist.
2. Since sense-data existed in the mind, then all things that could be known existed in a mind.
3. Reality was a product of some mind, and any "thing" not in some other mind does not exist.
"Ideas?"
1. Berkeley called the pieces of sense-data, or things that could
be immediately known, "ideas."
2. Memories and things imagined could also be immediately
known by virtue of the way the mind works and were also
called ideas.
Nothing could possibly exist or be known except these
"ideas."
Examples?
A tree
1. Something like a tree exists, according to Berkeley,
because someone perceives it.
2. What is real about a tree exists in its perception
an idea from which the famous philosophic idiom: esse is
percipi derives; the tree's being is in its being perceived.
esse is percipi
“TO BE IS TO BE PERCEIVED”
According to this argument, all of the qualities attributed to
objects are sense qualities.
But what if no human perceives the tree?
1. Berkeley admitted belief in an external world independent of
humans.
2.a His philosophy held that the world and everything in it was an
idea in the mind of God.
2.b What we call a real thing is the continuing "physical" object or
permanent idea in God's mind.
3. Our minds participate in God's perceptions, and thus
different people's differing perceptions of the same object are
variable but similar because each is of a piece with the same
thing.