Core Resources 4 – Representative Realism Key terms

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Core Resources 4 – Representative Realism
Key terms: Representative realism, sense-data
When we make arguments in favour of what we will call representative realism, we
are also making arguments against direct realism. Representative realism is also
known as indirect realism. When we make arguments in favour of representative
or indirect realism we are showing why direct realism cannot be true.
Representative realism is the theory that we don’t experience physical objects
directly but that we experience them through a ‘representation’ known as sensedata. They agree that we perceive a world of physical objects external to our
minds but they say that we do this indirectly. What we perceive are sense-data.
The three important arguments for representative realism are (these are also
arguments against direct realism):
1) Colours looking different in different circumstances
2) Illusions such as when the stick looks bent under water
3) Hallucinations – if I hallucinate I am seeing an elephant and there is no
elephant, what am I perceiving?
4) Science – science describes the world as a collection of particles and forces
moving in space that are in some cases different from what we perceive.
What is it therefore that we perceive?
For representative realists we directly perceive sense-data. What are sense-data?
1) Sense-data are part of the mind and they do not exist physically.
2) Sense-data are private because they are a part of your consciousness.
Physical objects are public. Many people can see the same table but only
one person can have sense-data of that table.
3) Sense-data are exactly as they appear to be. Physical objects can appear to
be different from how they are but sense-data are appearances.
There is one more important argument for sense-data and that comes from
hallucination. It seems like when we perceive things differently from how they
are – such as an illusion – what we perceive are sense data. But the
representative realist argues that actually there is no difference between
when we when we see an illusion or hallucination and ‘normal’ perception. If
someone doesn’t know that sticks look bent in water, when he perceives the
stick he would think it was bent. When one is hallucinating, you don’t know you
are hallucinating. You can’t tell, just by how something seems, whether you are
perceiving an illusion, perceiving the world as it really is, or hallucinating. So, if
you can’t tell the difference between the ‘mistaken’ cases or illusion and
hallucination and the cases in which we perceive the world as it is, we should
say we perceive sense-data in every case. We can’t tell the difference between
the sense-data of an illusion/hallucination and sense-data as we perceive the
world ‘accurately’. Therefore we don’t just perceive sense-data in these cases of
hallucination and illusion; we always perceive sense-data. In accurate or
veridical perception, we perceive the world in virtue of perceiving sense data.
Now we are going to move onto some criticisms of representative realism, but
before we do, make sure that everyone in your group fully understands and
would be able to explain what a representative realists beliefs are and their
reasons for them.
You might want to ‘adjust’ or change this picture to illustrate what they believe.
Objection to representative realism: How could we know the relation
between sense-data and physical objects?
If we don’t directly perceive physical objects and we only perceive sense-data,
how can we think about a world ‘beyond’ sense-data? If all that we perceive is
sense-data, how can we know about anything beyond that? What grounds do
we have for arguing that a ‘real-world’ of physical objects exists at all?
We could argue that we know what the world is like and that it exists because
sense-data resemble the world in primary qualities but not in secondary
qualities.
Berkeley argued against primary and secondary qualities resembling each
other by saying that in order to say that two things resemble each other you
must be able to compare them. But you can never compare sense-data to the
world of physical objects since you only ever perceive sense data immediately.
We can’t argue that real physical objects have size and shape unless we are
sure our sense data resemble them; but we don’t know whether our sense-data
resemble them unless we can say that they have size and shape.
To get around this, representative realists argued that sense-data are caused by
physical objects. But Hume argued that we cannot know just from our sensedata what causes them. Perceptual experience gives us sense-data but in order
to say that this is caused by physical objects, we must first know that physical
objects exists. If we only experience sense-data, we cannot know that physical
objects exist. Physical objects are therefore, according to Hume, a theory to
explain our sense-data.
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