Perception Flashcards
Direct Realism
The immediate objects of perception are mind-independent objects and their properties.
We perceive them directly.
Direct Realism Counters
Argument from illusion.
Argument from perceptual variation (Russel).
Argument from hallucination.
Time lag argument.
Indirect Realism
The immediate objects of perception are mind-dependent objects that are caused by and represent mind-independent objects. We indirectly perceive physical objects, via sense-data.
Indirect Realism Counters
Leads to scepticism about the existence of the external world (veil of perception).
If all we experience is sense-data, how do we know physical objects exist at all?
Indirect Realism Responses
External world is best hypothesis (Russel).
Coherence of senses and involuntary nature of our experience (Locke).
Distinction between primary and secondary qualities (Russel).
Idealism
The immediate objects of perception are mind-dependent ideas. Claims that all that exists are minds and ideas, rejects the idea of a mind-independent world (realism). Unless an object is being perceived by a mind, it doesn’t exist.
Idealism Counters
Leads to solipsism.
No adequate account of illusions or hallucinations.
Problems with role of God.
Hallucinations Response
Hallucinations are a completely different type of mental state to perception. Cannot generalise from hallucinations.
Time-lag Response
Only showing that when we think about how we perceive objects we should conclude that we are seeing the past.
Primary Qualities
Extension, shape, motion
Secondary Qualities
Colours, sounds, tastes
Perceptual Variation
Different people perceive the same object differently. What each person sees is how the object appears to them, a mind-dependent appearance. The perception changes the objects itself does not. Therefore, physical objects are not perceived directly.
Indirect Realism and Primary, Secondary Qualities.
In indirect realism, Locke argues that sense-data only resembles the world in respect of primary qualities. Indirect realists can argue that the world only has primary qualities ‘in itself’, but we perceive it as having secondary ones. What we perceive is different to how the real world actually is.
Berkeley’s Master Argument
Claims we cannot conceive of anything existing independent of our minds. Whenever we try to think of an unperceived and mind-independent object we are perceiving it and so it is not mind-independent. So as soon as we think of it, it becomes mind-dependent, so the idea of mind-independent objects is inconceivable.
Idealism’s attack on Locke’s primary/secondary qualities.
Berkeley agrees with Locke on secondary qualities being mind-dependent.
Berkeley goes further and argues that primary qualities are also mind-dependent. He presents various examples where primary qualities differ depending on the perceiver. Smooth surface may look jagged under microscope.
Shows that primary qualities are just as mind-dependent as secondary qualities are, everything we perceive is either a primary or secondary quality, so everything is mind-dependent and realism is false.
Master Argument Counter
Berkeley conflates the idea of an object with the object itself. Of course it is impossible to think of something that mind-independent, because the thought itself is mind-dependent. Just because we can’t think of something that mind-independent, it doesn’t follow that a mind-independent object is itself impossible.
Idealism’s attack on the veil of perception
The veil of perception disappears when we realise the physical world is actually just refers to a bundle of ideas. Ideas are reality, so it doesn’t make sense for there to be a veil of perception between these ideas and reality.
Idealism - God as cause of perceptions
I cannot on control my perceptions.
Ideas cannot cause anything.
Given the complex manner of my perceptions, the cause must be another mind - God.
Berkeley says “to be is to be perceived” but this means that objects don’t exist when we are not perceiving them. But this doesn’t seem to be true (rotting apple example). Berkeley’s response is that all ‘objects’ exist constantly in the mind of God.
Idealism Counters
Problem with the role of God.
Solipsism.
Illusions.
Hallucinations.
Idealism’s response to problem with role of God
We perceive copies of ideas that exist in God’s understanding. Although God does not perceive perceive sensations such as pain, he understands what is it is for us to undergo these sensations. Our changing perceptions are what God actively wills us the perceive.
Idealism’s response to Solipsism
Does provide argument for one other mind (God.
Mill does argue that we can infer the existence of minds by analogy to our own experience.
Idealism’s response to Illusion
In some sense, pencil really is crooked. The mind-independent object doesn’t exist, just the idea.
Although sometime such perceptions are misleading as it would be a mistake to assume the pencil would also feel crooked.
Idealism’s response to hallucinations
Products of imagination, even though there are some cases where imagination is involuntary (dreams). We are cause of our perception in hallcinations and dreams.
We cantell them apart, hallucinations are “dim, irregular and confused” whereas ordinary perceptions are “more vivid and clear”.
