Issues with Berkeley’s idealism

• Another objection is that Berkeley's argument, if valid, would show that I could not make sense of the idea of anything existing outside of my mind
• If Berkeley's argument is valid, it would lead directly to solipsism
• Berkeley's appeal to God as the eternal perceiver would be undermined and so his whole system defeated
• Without being able to compare our ideas with reality we have no way of establishing any such resemblance
• Defenders of indirect realism might appeal to the arguments for the existence of an external world that we have already examined, such as that it is the best explanation of our experience
• If we accept that a material world is the cause of our ideas, then it seems plausible to suppose that there will be a systematic correlation between reality and our perception of it
• Common sense says that imagined things depend on the mind, but real things are importantly different
• The difference is usually understood as being to do with their mind-independent existence
• Berkeley's response is that we can distinguish objects of the imagination because firstly they are subject to the will: I am in control of conjuring them into existence
• When I imagine a tree it is far less vivid and clear than when I actually perceive one
• For realists, this distinction is relatively straightforward: illusions occur when our mind-dependent sense data mislead us about mind-independent reality, and hallucinations occur when there is nothing in reality corresponding with the sense data
• If there is no mind-independent reality, then illusions and hallucinations would appear to be no different from veridical perceptions
• Berkeley's response is to argue that, when subject to an illusion, I am not mistaken about the actual sense data or ideas
• The reason we regard them as illusory is because they incline us to make false inferences about what we may perceive next
• If I judge on the basis of seeing an oar appear half bent in water that it will also feel bent to the touch, then I will be making an error
• If I try to grab a dagger which I see before me but catch only thin air, then I have been fooled by a hallucination
• The error in both cases lies in the inference made about further sense data because I judged I would have certain tactile sensations which were not forthcoming
• Berkeley's reasoning seems to imply that he would find himself in and out of existence every time he closes his eyes
• Berkeley's theory doesn't claim that things can only exist in my mind, but that they exist in the mind of God
• Berkeley argues that God is the permanent mind that is perceiving
• Berkeley can make sense of the idea of God, but not of any other mind, so we are plunged back into solipsism
• Berkeley's response is to admit that I cannot have an idea of God, as God's mind is not the sort of thing which has sensible qualities and so is not something I can frame in my mind
• Berkeley claims I am aware that there is a self which possesses my ideas, and this self is something unextended and indivisible
• Berkeley thinks he has satisfactorily proved that God can exist as what sustains the universe in existence
• Berkeley thinks I can extend this notion of myself by enlarging my own powers and subtracting my imperfections to produce a notion of the mind of God
• Berkeley believes he has demonstrated that the philosophical idea of matter is incoherent
• Berkeley agrees with Locke and Russell that the regularity and predictability of our sense data, the fact that they are not subject to my will and that the different senses cohere with each other, all show that the source of them is external to me
• Berkeley's conclusion is that the source of sense data must be a mind, and a very powerful mind
• Berkeley doesn't consider himself to have brought in God to save his theory, but rather his arguments have inexorably led to the existence of God as the only possible explanation of our experience
• The objection can be made that Berkeley's appeal to God is not a better explanation of our experience than matter
• Matter may be defended as the better explanation because it gives a better account of illusions and hallucinations and of the underlying processes which bring about our sense experiences
• Berkeley claims that what we perceive is in the mind of God
• It follows that the idea of pain is in the mind of God; in other words God suffers pain
• But if God suffers pain, then he is imperfect
• God is defined as a perfect being
• Therefore Berkeley's views lead to a contradiction
• Berkeley's response is that while God knows what it is for us to suffer pain, he doesn't suffer it himself
• God doesn't have a body and so God does not suffer from pain or other sensations against his will
• Because he is a pure spirit and actively determines his ideas he cannot be said to passively suffer from pain or any other sensation
• However, there remains a problem that if God has sensations, then he must change, and if he changes then he cannot be perfect and immutable