direct and indirect realism

• What is Direct Realism

  The immediate objects of perception are mind-independent objects and their properties.

   we directly perceive these objects with no intermediary 

  and they retain their properties when not observed.

  they occupy space and are composed of matter, have properties' like size colour etc.
• advantages of Direct realism

  its the common sense theory of perception- we should lead with common sense unless it leads to inconsistency-Russell

  avoids scepticism- doesn't arise as we have direct contact with the world

  explains why we mostly agree on the the way the world is 
• Argument from illusion

  p1- when subject to an illusion, an object appears to have a particular quality

  p2-  the perceiver is directly aware of this apparent property (e.g bent straw)

  p3- in reality the object does not have this property

  C1- So what the perceiver is directly aware of and what is real are distinct.

  C2- So direct realism is false-we don't see physical objects directly
• Response to argument from illusion

  they deny p2

  they say that you are directly aware of the straw appearing a certain way- a looks property

  sense datum and actual object are not distinct
• Argument from hallucination

  p1- hallucinations occur when a person perceives something which does not exist outside the mind

  C1- what they perceive exists only in their minds

  p2- hallucinations can be subjectively indistinguishable from veridical perceptions

  p3- common kind claim: if hallucinations and v.p are indistinguishable then in both cases we must be aware of the same thing (sense data)

  C2- So what we are aware in v.p must also be in the mind.

  C3- hence we perceive the world indirectly through sense data and direct realism is false
• Response to argument from hallucination 

  reject common kind claim- just because two experiences are indistinguishable does not mean they are the same

  hallucination and v.p are different (disjunctivism) real and forged Picasso painting may seem indistinguishable 

  * a indirect realist would then respond by saying that perceptual experiences are result of casual chain (photons eyes brain etc.) if we can stimulate the brain using a different casual chain (matrix, hallucination) and get same response then it is the same experience (sense data)
• Argument from perceptual variation 

  P1- the apparent properties of objects can vary (i.e table look like diamond)

  P2- but the real properties stay the same

  P3- direct realism claims that objects have the properties that they appear to have

  C1- direct realism must be false
• response to argument from perceptual v.

  relational properties- 

  these are properties that an object has due to its relation with the observer

  table looks diamond but is still same table perceived directly

  *Indirect realist response so many ways to perceive objects that there is an infinite number of looks properties 

  how do we know an actual property is? problem as how are we then supposed to have direct contact with reality as it is
• Time-lag argument

  P1-since light takes time to travel what we are seeing may no longer exist 

  P2-so what we are seeing and what is are different

  C- what we see are appearances, not actual objects, direct realism is false as it says we have direct contact with reality as it is 
• Response to Time-lag argument 

  perception gives us direct knowledge of the world as it was rather then as it is

  in most cases time lag is small/insignificant
• Indirect realism 


  is the view that the immediate objects of perception are sense data (representations) and that the physical world of mind independent objects are indirectly perceived through these representations
• what is sense data

  the content of perceptual experience, it exists only in the mind, only exist when being experienced and are exactly as they seem/appear. 

  caused and represent real mind-independent objects- the objects stay the same even if sense data changes
•  primary and secondary qualities

  object possesses independent of us- our ideas of p.q resemble the q of the object

  for example: motion, solidity, texture

  secondary- are the powers in objects to produce properties in us (our minds) caused by interaction with the object- our ideas of s.q don't resemble the powers that cause them

  for example: sound, taste, colour
• AFP&SQ: P.Q are measurable

  (not argument from Locke)

  primary qualities are mathematically measurable (speed, size)

  there are no ways of measuring taste or smell

  objection: cant measure with senses, with proper equipment can measure sound and colour etc. so argument falls apart
• AFP&SQ: P.Q are essential to objects existence

  Locke thinks pq are essential to the object and cannot be lost. 

  he gives the example of a grain of wheat still has size number solidity etc.- no matter how many times you divide it.

  objection: 1- both P&S qualities can change when

  object is altered but neither go from existence- wheat will have colour still

  2- goes against original defin. of sq as powers 

  in the object so wouldn't be lost- seeing the wheat under microscope would still be colour etc. 
• AFP&SQ: P.Q are accessible to more than one sense

  rectangular table- looks rectangular and feels rectangular, touch and shape

  see something moving and feel it hit you

  red for example is only red to one sense

  heat one sense

  objection: dependent on the senses we have as humans, if we didn't have sight then touch would then be classified as s.q, if we could sense colour with our hands then colour would  be P.q
• Issues with indirect realism: scepticism about external world

  indirect realism says we are directly aware of sense data and must infer the existence of objects beyond the mind

  we have no access to the real world

  a veil has been lowered over us we cant see past it

  so the sceptical question of if we can know anything about the real world. or if it is really there
• Response to issue with IR: Scepticism about external world Locke

  involuntary nature of our experiences

  Locke points out we arent in control of our sense data. Because perception is not subject to our will it doesn't come from us 

  therefore the source of sensation must be external
• Response to issue with IR: Scepticism about external world Lock and Cockburn

  The coherence of various kinds of experiences

  • Lockethat our senses can cohere, we can see fire and feel the heat. 

  Cockburn- we learn to associate the way objects feel to the touch and appear to the eye through long association 

  So the senses independently offer support for each others testimonies - suggesting that there is one external cause of both set of perceptions
• Criticism of coherence of various kinds of experiences

  that they are not deductively valid arguments

  it is possible for coherence of senses in dreams 

  However Locke is aware of this and think that these arguments show that the inference of the real world is reasonable. this is as far as we can go/know given our limitations as creatures
• The Molyneux question- argument against coherence of senses IR

  the question of if a blind person who feels objects would be able to recognise these objects If they were to gain sight.

  Molyneux says no

  Berkley thinks there is no resemblance between senses

  However CT Cockburn agrees but thinks that coherence can be learnt and that it is a good argument for external world
• Response to issue with IR: Scepticism about external world Russell best hypothesis-simplest

  Best hypothesis theory

  he accepts there is no deductive proof of the nature of external world

  but that scepticism can be resisted 

  Its the best hypothesis that as it gives us a reason why our perceptions are systematic (cat example) and coherent. rather than incoherent in dreams. 

  ^ he is appealing to a kind of Occams razor, that the best explanation is the simplest one which explains available data.
• response to issue with IR: Scepticism about external world Russell best hypothesis-agreement with others

  Best Hypothesis theory

  people usually agree with us about what the world looks like 

  the best explanation for this is that we are all seeing the same world.

  Issue: Fallacy-Begs the Q. 

  its assumes the truth of what it is trying to prove if we don't know EW exists we cant assume other people exist to prove EW exists- circular reasoning

  Russel himself then rejects this argument 
• Response to issue with IR: Scepticism about external world Russell best hypothesis-regularities

  Best hypothesis theory

  EW is the best way to explain the types of sense data we experience

  Apple left in draw, open it week later rotten

  simplest way to explain this is that there is a real apple causing the sense data

  cat moving rooms etc.

  Criticism: Berkley says the simpler explanation is that apple exists in the mind of powerful spirit/God

  simpler as it only requires one thing ontologically: mind whereas IR needs to ontological categories: mind and matter
• Issues with IR: Berkley we cant know the nature of mind-independent objects

  P1- My idea of a tree has sensible qualities(i.e. green, tree shaped)

  p2- but these sensible qualities rely on the mind

  p3- to say my idea of the tree resembles the real tree is like saying something visible can resemble something invisible

  p4- our ideas are also fleeting and changing whereas Material objects are constant and permanent

  C1- anything outside the mind  cant have these qualities (sensible)

  C2- it follows that my ideas cannot then resemble a supposed material object 
• Responses to Berkley's argument we cant know the nature of mind independent objects/ veil of perception

  argument from survivalif our perceptions of the world around us had not been some what accurate we would have died out. 

  for example being able to pick the right berries from poisonous berries 

  • appeal to testimony of othersif everyone sees something roughly similar to how i do then it must be evidence that it is close to reality