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Naïve/ Common Sense/ Direct Realism
What is it?
- There is an external world/ objects in the world cause our sense perceptions
- we learn of the world through our sense
- Things are as they appear
- Instinctual belief of most people
Criticisms
- Illusion – constantly encounter ‘every day’ illusions, if world is at it seems then these illusions must be true since are indistinguishable from other sense perceptions. E.g. stick in the water or phantom limb
- Perception – the world is often not perceived as imagine to be. For example, that tree is smaller in the distance and the table has patches of light and dark red due to the light. How do we know what to trust?
- Hallucination – if world is as it appears what do we make of hallucinations/dreams? Are the pink elephants of a drunken person’s visions actually real? Inclined to say no – suggests other factors.
- Circularity – claiming that we know how the world actually is through the senses requires that we know how the world actually is.
- Different perceptions – other creatures – or even people – cannot all be perceiving the same world
Strengths and Counters
- Strawson counter on illusion/ sense data – variation in the way perception = part of naïve realism because ‘what we think depends on context’. Might say ‘it looks like x’ but say ‘I see x’ on closer inspection. If sense-data theory true, should always say ‘It looks like x’ as can never be sure actually is it.
- McSomething counter on hallucination – might not see any hallucinogenic difference subjectively, but very much difference from external (objective/our) perspective. Therefore, hallucinations are distinguishable from perceptions.
- ME on instinct – this is our instinctual belief. This implies it is reliable, simple and PRACTICAL so why reject it when it works?
- When we have illusions cannot be perceiving directly
- Must perceive something else - a mental object.
- Not possible to tell the difference between illusions and reality
- follows that on all occasions we are not directly perceiving physical objects. Rather we are perceiving mental objects (often known as sense-data)
Representative Realism
What is it?
- There is an external world/ objects in the world cause our sense perceptions
- We learn of the world through our sense perceptions constructed from sense data (which the objects cause).
- These sense perceptions are mediated in some way.
- Often coupled with ‘primary’ - e.g. size - and ‘secondary’ - e.g. taste - qualities to counter variability of qualities.
Criticisms/ Weaknessses
- Real world – like direct realism, assumes the world exists
- Veil of Perception – we are each behind a ‘veil’ – we receive sense data but can never know what is beyond it. Does the world really exist?
- Uknowableness – the theory makes the real world unknowable – can only ever know about how the world appears to us.
- Berkley on inseparability – sensation/ sense data distinction may be intellectually possible but not practically. For example, surely shape is just the boundary of colour?
- Causality/ representation – how can we be sure of this? In order to know that A cause/ represents B we must be able to experience both independently
Strengths and Counters
- Account for illusions – if the world is only a representation then it is understandable that we should sometimes interpret this wrong
- Supported by modern science – many modern scientific theories seem to agree with this – i.e. those about light.
- Against veil of perception (Descartes style?)
- Have no control over our sense perceptions
- Without sense organs, do not perceive
- Senses agree with each other
- Russel against veil/ idealism – to suggest the world exists is the simpler/ instinctual reaction (although nothing logically forces us to hold one view or the other)
- Me – see direct realism above
Idealism
What is it?
- There is no external world
- All that exists is minds and their ideas
- To be is to be perceived (see phenomenalism)
- All properties of object are sense perception dependent (as all sense data = secondary and therefore dependent on object).
- An object is the sum of its properties
- Therefore, all objects are sense dependent
- Objects are a stable (coherent/ orderly) collection of perceptions which are created when we perceive them
- Anti-realist
Criticisms/ Weaknesses
- Berkley’s error – cannot conceive of non-conceived tree ≠ cannot conceive of tree existing without conception
- Simplicity/ instinct –external object is simpler than to suppose that a new perception (object) pops into existence when perceiving.
- Veil of perception – just pushes back further. What are the sense perceptions? Where do they come from? Why are they coherent?
- Scepticism – forces solipsism on us. Have no reason to suppose anything exists except our mind
- Hallucinations – what is to suppose that these are not ‘real’?
Strengths/ Counters
- Avoids ‘veil of perception’ – argues that veil makes concept of matter meaningless and therefore disregards it
- Gives an account of what the world is
Phenomenalism/ Sense Data Theory (linguistic)
(An Idealism/ Realism middle ground…)
What is it?=
- World exists (but not in realist sense)
- Learn of world through senses (in a Foundationalist way?):
- objects = families of ACTUAL/ POSSIBLE sense exp./data
- Physical existence: “permanent possibility of sensation” (see idealism!)
- sense experience reducible to indubitable sense data (added later – deals with problem of unperceived perceptions)
- object claim make implicit prediction of possible sense experience + therefore open to empirical error!
- (Must be verified before can make certain claim – object does/doesn’t exist only after we fulfil conditions of perception. Some take further i.e. always possibility of error due to infinite range of possible sense data)
Criticisms
- Sense data reductions – can object statements be reduced to sense data?
- Object – sense data would have to be (for some) an infinitely long list – surely impossibility?
- Space – requires we state where sense data would occur. BUT, space refers only to physical/spatial juxtaposition.
- I – surely we are objects? How do we reduce ourselves?
- Sense data certainty/ purity – ‘I see red’ ≠ naming that sensation, but describing. We relate it to all the red OBJECTS we have seen. (use language of involves physical; beyond momentary sense datum).
- Counter intuitive – Russel/ Occoms razor/ instinct type arguments.
- Perceptual Ambiguity – may be multiple (or uncertain) hypotheses for the same sense data. How do we determine/ define correctly in phen. terms? E.g. white paper may appear red under red light and red paper may appear red under white light. How do we express this as sense data?
- Possible Sense data etc. – what is this? Some kind of non-material object? How can there be an unperceived perception?
- Scepticism – seems to force scepticism; seems to suggest always possible new sense data refutes logical inference
- Originating – where do the sense data come from? Surely coherence/ order etc. suggests a physical cause? Can we accept that they ‘just are’ in the same way we would a physical world?
Strengths
- Accounts for illusions etc. (implicit prediction)
- Accounts for object existence when not being perceived (take that idealism!)
- Logical (kind of) and Foundationalist
Scepticism – illusion, dreaming, deception
- Illusion – our senses sometimes perceive us, so how do we know that they won’t always do so? Black tower example (Descartes)
- Dreaming – have had dreams before that were indistinguishable with reality; how do we know we are not doing so now?
- Deception – it is possible that we are being deceived in our perceptions. How do we know that we are not being? E.g. could be just a brain in a vat/ could be an evil demon which is constantly tricking us. How do we know this is not occurring?
Comparison
| Magical Comparison…
|
| -
| N. Realism
| R. Realism
| Idealism
| Phenomenalism
|
| World?
| Is as appears
| Represented to us
| None - only minds/ ideas
| Is actual/ possible sense perceptions
|
| Origin of Perceptions
| Objects
| Objects (through sense data)
| Minds (often)
| Erm…they just are?
|
| Major Objections
| Illusion
| Veil of Perception + nature of representation
| Simplicity/ Hallucinations
| (see above row), simplicity, forces scepticism
|
| Major Strength
| Not really… instinctive?
| Simple + accounts for perceptions
| Nothing logically constrains to believe in external world
| Accounts for many factors of perception
|
| Complicatedness
| ------ Increasing ----->
|
| Closeness to instincts
| <----- Increasing ------
|
Glossary
- Direct Realism – the belief that we receive our perceptions about the world in a direct and unmediated fashion – the world is as it appears.
- Representative Realism – the belief that our perceptions are mediated by our sense data such that our perceptions are just a representation of the physical world.
- Idealism – the belief that all the really exists is minds and their ideas such that there is no external world – just sense perceptions in the mind of the perceiver.
- Phenomenalism – the belief that objects consist of actual/possible sense perceptions. Often coupled with idea that sense perceptions are reducible to sense data.
- Sense-data – the raw sensations (often contended that we receive them from objects) which are interpreted to form sense perceptions.
- Illusion – a sceptical argument maintaining that everything could be an illusion.
- Dreaming - a sceptical argument maintaining that we could always be dreaming.
- Deception - a sceptical argument maintaining that we could be being deceived.
Also See
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