AQA Philosophy - Unit 1 - Epistemology - Part III

What are Problems of Perception

- Can have misperceptions or illusions, i.e. seeing something
in a way other than it really is.
- Can have hallucination, i.e. seeing something that is not
present at all.
- Cannot distinguish between veridical and non-veridical
instances of perception.
-

What are the three main theories of perception

1) Direct realism - 'Common sense' Theory (Thomas Reid)
2) Indirect realism - 'Representative Realism (John Locke)
3) Idealism - (Bishop Berkeley)

What is Direct Realism?

- The theory that the immediate objects of perception are
mind-INdependent objects (exist in an external world)
including all of their properties. The world is exactly as it
appears.
- Ergo, there is no distinct between primary and secondary
qualities.

What is Indirect Realism?

The immediate objects of perception are mind-dependent
objects that are caused by and represent the mind-
independent world.
- There IS a distinction between primary and secondary qualities.
- Sense-data represent the objects in the world around us.
- Nev

What is the problem with Ockham's Razor

- It would mean a primary school explanation of a certain subject is better than an A-Level standard explanation of the same subject because it is simpler.

What is Idealism?

An anti-realist theory which maintains that all our
experiences are of mental representations.
1) The external world exists. (Can't be disproved)
2) The external world is entirely mind-dependent.
3) Berkeley is not a sceptic.
4) There are only minds and i

What are the TWO forms of Direct Realism?

1) Naive direct realism = Maintains that objects retain all
their properties when unperceived.
2) Scientific (common) direct realism = Maintains that
objects just retain their primary qualities (not secondary).
when unperceived.

Why does Direct Realism make sense?

1) It is in accordance to common-sense. OBJECTION - A
philosophical position should not be determined by this.
2) The world is causally responsible for our perceptual
experiences.
3) The independence as material objects explains their
continued unperceive

What are the CHALLENGES to Direct Realism?

1) The ACTUAL GAP between the perceiver and the world;
how does one know the object they are looking at bares any
resemblance to what they perceive.
--> Leads to the TIME-LAG Argument:
A) There is a time lag between one's perception of an object
and the o

What are the CHALLENGES to Direct Realism
(CONTINUED)

- There seems to be a difference between the immediate
(direct) objects of perception, sense-datum, and the mediate
(indirect) object of perception, the stars themselves.
C) THEREFORE, Direct realism is FALSE.
2) Direct Realism cannot account for differen

REPLIES to the Challenges to Direct Realism?

1) The time-lag argument is based on a misunderstanding -
'immediate' is meant in the sense that nothing comes in
between the object and the perceiver, not in terms of time.
E.g. with the illusion of a duck and rabbit, it may take time
to find the image o

What is the Argument from Illusion
(against Direct Realism/ for Indirect Realism)?

1) We perceive something having some property F.
2) When we perceive something having some property F, then there is something that has this property. (assumes external world)
3) In an illusion, the physical object does not have the property F.
4) Therefo

What is the argument of hallucination
(against BOTH direct and indirect realism)

1) In a hallucination, we perceive something having some
property F.
2) When we perceive something having some property F, then there is something that has this property.
3) We don't perceive a physical object AT ALL (unlike in illusions).
4) Therefore, w

Outline and illustrate Russell's Table
& his Argument from Perceptual Variation
(against Direct Realism).`

1) There are variations in perception.
2) Our perception varies without corresponding changes in the physical object we perceive. (E.g. the desk remains rectangular, even if the way it looks to the perceiver changes from looking at it from different angle

Objections to Russell.
(Defence for Direct Realism)

1) The claim that "there is no good reason to say that one of the colours we experience the table as having is more REAL than the other" is FALSE; the colour attributed to that table is visible under normal conditions, and this ENCOMPASSES all the shades

What is the Disjunctive theory of Perception?
(Defence for Direct Realism)

- The direct realist can reply to the argument from illusion by claiming 'what is seen is how some physical object looks'. This does not work for the argument from hallucination as NO PHYSICAL OBJECT IS SEEN AT ALL.
- The DTP state that 'if something look

What is the Disjunctive theory of Perception?
(Defence for Direct Realism) (CONTINUED)

- Hallucination and veridical perception are two different mental states.
- The fact that hallucinations are subjectively indistinguishable from veridical perception tells us nothing significant about what perception is.
- Hallucination is only perceived.

Why is Indirect Realism a better theory than Direct Realism?

- Doesn't fail to explain why we have misperceptions and illusions. Realism is preserved by introducing sense-data.
- Whether one experiences a hallucination of an object, or actually sees the real object, the sense-datum is the same.

Why believe in sense data?

1) The primary-secondary quality distinction. (Objects don't 'really' have tastes).
2) Perceptual relativity. (Perceptual variation from different perspectives).
3) They explain misperception. (Stick is not really bent but the stick-sense-datum is.)
4) Th

How does Indirect Realism deal with the
'fallibility of one's knowledge of the external world'.

Our perceptual experiences are a reliable guide to how things are in the world, but things can go wrong in terms of causal links between the world and me, e.g. drugs disrupt normal perception, causing hallucinations.
- The explanation of our knowledge of

What are the TWO forms of Indirect Realism?

Naive form = Maintains that the inner object of awareness has the properties of all the kinds that the physical object also possesses.
Scientific form = (Common view used by Locke) Maintains that the (indirect) object out in the world only has primary qua

What are Primary and Secondary Qualities?

Primary Quality = A property which is completely inseparable from the object and is mind-independent.
Secondary Quality = A properties an object has by virtue of being perceived by an observer. Requires that the person possesses a particular sense. They d

What is the importance of the distinction between
Primary and Secondary Qualities?

1) The perceiver makes the vital contribution to the way in which it is experienced, e.g. the redness of a flower.
2) The dependence of secondary properties on that nature of the observer is further supported by the way in which sensible properties (colou

How does Locke show the Qualities?

1) Division of a grain still leaves smaller parts with extension. = Primary Qualities.
2) Pain and heat of a fire = Secondary Qualities.
- By altering an object you can change its secondary qualities but not its primary qualities.
OBJECTION - Berkeley - O

What is Russell's argument for Indirect realism
and the existence of the External World?

- Believes we do not know physical objects exist, just sense-data. Therefore, can't know the existence of other beings.
1) Either physical objects exist and cause my sense-data or physical objects do not exist nor cause my sense-data.
2) I can't prove eit

What is Locke's argument - on the lack of choice over our
experiences and the coherence of various senses?

1) I know from experience that I can change how a piece of paper looks by writing on it.
2) I can PLAN what to write, and I know it advance what the paper will look like.
3) But I cannot bring about the sense-data of seeing the paper with words on it just

Objections to Locke's argument.

1) Locke hasn't shown that physical objects exist - despite saying there must be an external cause of his sense data.
2) Doesn't add anything new to Russell's argument, just makes it stronger.

What is Berkeley's Idealism

1. When a physical object is perceived, nothing is perceived in addition to its primary and secondary qualities.
2. But as both primary and secondary qualities are mind-dependent, nothing is left to perceive to exist independently of the mind.
3. We can't

What does Idealism claim about physical objects?

Physical objects are bundles of ideas that we have come to associate each with each other because they 'are observed to accompany each other'.
(Objecting to Indirect Realism - Locke) -> Primary qualities don't resemble objects any more than secondary qual

THREE Good reasons for Idealism

- Although Idealism is counter intuitive:
1) LINKING PROBLEM - Unlike realism, Idealism solves the problem of scepticism, because there is no need to 'link' the ideas we perceive to something else (physical objects). [In experiencing ideas = experiencing

Berkeley's attack on Locke's resemblance.

- Locke argues that the squareness of a physical object RESEMBLES what we see.
- Berkeley argues that nothing resembles an idea, except ANOTHER idea. So it is meaningless to say that the shape of the table 'resembles' the shape we see. Between knowing the

What does Idealism/Berkeley say on the existence of mind?

AGAINST:
- Just as we can't form an idea of physical objects, we can't form an idea of the mind - as neither can be experienced by the mind directly. Ideas experienced can't resemble minds - since ideas are passive and minds are active.
FOR:
- Minds EXIST

Problem with Idealism regarding the
continuing existence of substance.

- While realism says that substance exist independent of perception, idealism doesn't.

How does Berkeley solve the problem of
the 'In-existence of unperceived objects'?

- A limerick was used to illustrate that a tree continues to be in the Quad because it is always observed by an omniscient God.

Why Idealism over the other theories?

1) Berkeley defends common sense and argues Locke's Indirect realism is incoherent.
2) It is the ideas (sense-data) of which the content we directly experience and are aware of.
3) There is a gap between the observer and the object of experience in the re

Criticism of Idealism

1) BERKELY's ERROR - Cannot conceive of non-perceived tree.
2) SIMPLICITY - Permanent external objects is simpler than to suppose that new perceived objects pop into existence whilst perceiving.
3) VEIL OF PERCEPTION - Where are sense perceptions, where d

What does Berkeley argue about the "Gap"?

1)It is only if physical objects are conceived as collections of ideas which hang together in experience that we have any empirical evidence for their evidence.
2) BOTH secondary and primary qualities mind-dependent, as it's impossible to conceive of prim

What is mentioned in Berkeley's
Principles of Human Knowledge?

We are COMPELLED to believe that:
a) We directly perceive ideas, and the content of our experience is ground in our perception of qualities.
b) There is something distinct from what is perceived - the mind.
c) One's ideas cannot exist except in the mind.

What is mentioned in Berkeley's
Principles of Human Knowledge? (CONTINUED)

For idealism:
g) For objects which are not perceived nor exist in the mind, they MUST have NO EXISTENCE at all, or must be in the mind of God.
Master Argument: THEREFORE, conceiving something means that it's existence is necessarily MIND-DEPENDENT.
Realit

What are the CHALLENGES to Idealism?

1) It's obviously false that there is no matter and just ideas.
REPLY - there is nothing in experience that can show Idealism to be false.
2) It is not necessary that it must be 'God' that is keeping things in existence when we are not looking at them.
3)

Berkeley on Secondary Qualities

1) A cloud from a distance looks pink, but up close, it loses its colour (or appears grey).
2) A solid physical object, viewed through a microscope, appears to have different colours than those it has when viewed normally.
3) Different animals perceive th

Berkeley's attack on the primary/secondary
quality distinction

1) What looks small to me may look huge to a small animal.
2) What looks small from a distance looks large when viewed close up.
3) What looks smooth to the naked eye appears craggy and uneven under a microscope.
4) If you look at a circle straight on, it

Berkeley's attack on the primary/secondary
quality distinction (CONTINUED)

6) In the case of colour, when an object appears to have many colours, depending on how it is perceived, we can't say that it has one real colour which is independent of how we perceive it.
7) Therefore, (1)-(5) show that we can't say that an object has o

What are the problems arising from the
view that mind-dependent objects?

LOCKE ON RESEMBLANCE:
- He adds that our perceptual experiences of primary qualities RESEMBLE the actual primary qualities of the object.
- Our secondary qualities of the object have NO RESEMBLANCE to th object at all.
PROBLEM - How can variable perceptio

How can sense-data indicate the RELATIONS
between objects? (Defence for Indirect realism)

When looking around a penny, all sense-data represent the penny because they are SYSTEMATICALLY related to it.
Therefore, we can explain how these sense-data represent physical objects in term of this complex causation.

What does Russell argue about
'Physical space compared to our experience of spatial things'

The relative positions of physical objects in real space correspond to the relative positions of sense data in a apparent space, e.g. it takes longer to work to a physical house that is perceived to be further away, than one that appears to be nearer.
- S

Problems arising from the view that mind-dependent
objects are caused by mind-INdependent object
(favour IDEALISM)

- Russell's argument required that our mind causally effected by physical objects.
PROBLEM - Of Mind-Body Problem

Berkeley's Idealism

Berkeley argues that what is perceived by the senses are qualities and nothing more:
1) Through vision, we perceive colours, shapes, size, etc.; through hearing, sounds; through smell, odours - and so on. Each sense perceives particular types of qualities

First of Berkeley's FOUR Arguments

Hylas has not been persuaded that primary qualities are just as mind-dependent as secondary qualities. So Philonous tries another approach:
1) A physical object will need to be of some size or other.
2) What distinguishes one size from another size is som

Objections to Berkeley's First Argument

1) This argument is unclear and unpersuasive and rejected by Locke.
2) Despite not being able to conceive of something as merely having size or shape, we can have a coherent conception of something as having only size, shape and solidity - all primary qua

Berkeley's Second argument

Hylas argues that we need the idea of 'a material substratum' - the stuff or substance that possesses primary and secondary qualities and holds them together to make one thing, one physical object.
- This 'material substratum' can exist unperceived.
- Be

Objections to Berkeley's Second Argument

1) Locke saw the point, and accepted that the idea of substance was the idea of something unknown
2) A realist view of physical objects involves a mystery. Worse, Berkeley argues, it is quite literally inconceivable - we can say nothing about how it exist

Berkeley' Third Argument

Berkeley argues that neither our senses nor reason supports such a claim:
A) As argued previously, all we perceive are primary and secondary qualities, not mind-independent physical objects.
B) Therefore, our experience cannot verify the hypothesis that t

What is Berkeley's Master Argument?

1) Thoughts cannot exist outside the mind - thoughts are psychological events or states.
2) Therefore, my thinking of a tree is not mind-independent. It is impossible (inconceivable) that there is a thought of a tree when no one is thinking of a tree.
3)

Berkeley's Idealism - Further

1) As (the ideas that comprise) physical objects are mind-dependent, there are three possible causes of my perceptions: ideas, my mind, and another mind.
2) Ideas themselves don't cause anything.
3) If physical objects depended on my mind, then I would be

Objections to Berkeley

1) Hylas says 'to be perceived is one thing and to exist is another'. If things cannot exist when we are not perceiving them, then when they are not being perceived, they cease to exist! This is very counter-intuitive.
2) Idealism does not give an adequat

Objections to Berkeley (CONTINUED)

4) Idealism leads to solipsism. Solipsism is the view that only oneself, one's mind, exists. There are no mind-
independent physical objects and there are no other minds either. We can object that Berkeley's four arguments against mind-independent objects

1) Hylas says 'to be perceived is one thing and to exist is another'. If things cannot exist when we are not perceiving them, then when they are not being perceived, they cease to exist! This is very counter-intuitive.

REPLY - when we are not perceiving them, physical objects still exist in the mind of God. [The inaccuracy is the suggestion that God observes the tree. Berkeley says that the tree (which is a bundle of ideas) is comprehended by and exists in the mind of G

[REPLY - ILLUSIONS]
2) Idealism does not give an adequate account of illusions and hallucinations. Since we perceive ideas, there must be an idea that corresponds to the illusion. But we don't want to say that the physical object is as it looks in the ill

REPLY - ILLUSIONS:
- We aren't misperceiving - what we perceive in the case of the half-submerged oar is crooked.
- [However, this is misleading if we infer that the oar would feel crooked if we touched it or would look crooked when pulled out of the wate

[REPLY - HALLUCINATIONS]
2) Idealism does not give an adequate account of illusions and hallucinations. Since we perceive ideas, there must be an idea that corresponds to the illusion. But we don't want to say that the physical object is as it looks in th

REPLY - HALLUCINATIONS:
- Berkeley provides two other criteria that mark off hallucinations from perception.
- First, they are 'dim, irregular, and confused'. Second, even if they were as 'vivid and clear' as perceptions, they are not coherently connected

3) Idealism cannot secure objective space and time. For there to be objective space and time, there need to be mind-independent physical objects. But according to Berkeley, physical objects are ideas --> there is no gap between appearance and reality -->

REPLY - We see the same tree in the sense of 'exactly resembling'. The tree you see is qualitatively identical to the tree I see. But this reply runs counter to common sense. Surely you and I can look at one and the same tree. Realism, of course, says we

4) Idealism leads to solipsism. Solipsism is the view that only oneself, one's mind, exists. There are no mind-
independent physical objects and there are no other minds either. We can object that Berkeley's four arguments against mind-independent objects

REPLY (not actually made) - Berkeley makes a number of remarks we can draw upon. He accepts that 'strictly speaking', I have no idea of a mind. But because I am a mind - a 'thinking substance' - I know I exist.

5) Whether God can used to play the role he does: The exact relationship between ideas in the mind of God and what we perceive is puzzling. Berkeley has said that physical objects exist in the mind of God, but:
A) What I perceive is in my mind, not God's

REPLY:
- Berkeley makes the following points in response:
1) What I perceive is a copy of the idea in God's mind.
2) The ideas of physical objects exist in God's mind not as perceptions, but as part of God's understanding.
3) So while God doesn't feel pai

Why should sense-data be rejected
(against Indirect Realism/favouring Direct Realism)?

1) The object/appearance argument is mistaken. (if X looks to have property P, then it is a mistake to think there is something else that is P)
2) There is no indication of where sense-data are - they're not in the external world.
3) If one can only perce

Replies to the challenges to Sense-data

1) It's part of common-sense realism to allow for variance in the way things looks, in different concepts.
2) There is a difference between the experiences of a person having veridical perception VS non-veridical perception of the same object. - Yet, we h

Replies to the challenges to Sense-data
(CONTINUED)

4) Perceptual states are caused by objects in the world and this causal relation is unpacked by mechanisms, i.e. the briain.
- SO, if there is a causal connection between our internal brain states and the world, then misperception and non-veridical percep