Idealism

Idealism

The view that the immediate objects of perception are mind-dependent ideas, and that mind-independent physical objects do not exist.

Esse est percipi

To be is to be perceived

Berkeley’s challenge to the primary/secondary quality distinction

Berkeley argues that primary qualities (shape, size, motion) vary with perspective and conditions, so they are just as mind-dependent as secondary qualities.

The Master Argument

When you try to imagine an unperceived object, you are perceiving it in your mind, so it is impossible to conceive of an object existing unperceived.

Illusion and hallucination under idealism

If all objects are mind-dependent ideas, then illusions and hallucinations are not fundamentally different from ordinary perception.

Berkeley’s response to illusion and hallucination

Ideas caused by God are involuntary, coherent, and follow natural laws, while ideas from imagination or dreams are voluntary and less consistent.

Solipsism problem for idealism

If objects only exist when perceived, it may seem that only one’s own mind exists, making the existence of other minds uncertain.

Berkeley’s response to solipsism

Objects continue to exist because they are always perceived by God, an infinite and ever-perceiving mind.

Problem of God’s perception

If sensory ideas involve sensations like colour or pain, and God cannot experience sensations, it is unclear how sensory ideas can exist in God’s mind.

Berkeley’s response about God

God understands ideas intellectually rather than experiencing them phenomenally and causes our sensory ideas according to the laws of nature.