Unit 1 - Perception Flashcards
What is direct realism?
Direct realism is the concept that we directly perceive physical objects and their properties because they exist independently of our minds. All the properties of the physical objects are in the object
State 3 features of direct realism
- physical objects exist independently of our minds
- properties of physical objects are in the object
- what we immediately perceive is what is reality
What is the structure for this question?
Outline and explain the argument for perceptual variation
- perceptual variation is one of the arguments that challenge direct realism
- explain direct realism
- how does perceptual variation challenge direct realism
- explain perceptual variation with and example
- therefore direct realism is false
- what part of direct realism does perceptual variation challenge
Explain the argument from perceptual variation (premises and conclusion)
- There are variations in our perceptions
- Our perception varies without corresponding changes in the physical object
- Therefore the properties the object has and the ones we perceive are not identical
- What we directly perceive is not the same as what exists independent of our minds
- Therefore, direct realism is false
What does the perceptual variation argument say we perceive instead of physical objects?
Sense data
What is sense data? 5 points
- They are what we immediately perceive, as we see/hear/experience is now - we perceive indirectly through sense data
- They are the content of our sensation
- They are private, personal and different for everyone
- They are mind dependent because everyone’s minds are different
- So there may be no way to tell how things exist in reality
How do direct realists respond to the perceptual variation/illusion argument? (Premises and conclusion)
- Perceptions only vary because people are not perceiving the object under normal conditions (ex, light)
- Physical objects have “relational properties” inside of them which are mind independent
- “Relational properties” are the ability to “appear” as if having a different property in relation to the perceiver
- “Relational properties” are mind independent because the variations are due to the physical object, not us.
- Therefore sense data doesn’t exist
What is an illusion?
An illusion is when what we perceive is not what is real, it is deceiving
Name the 4 arguments that challenge direct realism
- perceptual variation
- illusion
- hallucination
- time lag/light
Explain the argument from illusion (premises and conclusion)
- We know there are illusions in perception
- We perceive illusions without corresponding changes in the physical object
- Therefore the properties the objects appear to have are not the same as the ones we perceive
- What we immediately perceive is not identical to what exists independently of our minds
- Therefore we do not perceive physical objects directly
- Therefore, direct realism is false
Give an example for the illusion argument
- According to direct realists, if I perceive a stick in water and it appears crooked, then it really is crooked
- However, we know that the stick remains straight even when it is in the water
- Therefore the properties the stick has and the ones we perceive are not the same
- Therefore direct realism is false
How do direct realists respond to the argument from illusion?
(Same as perceptual variation)
Physical objects have relational properties that allow them to appear to have different properties
In the crooked stuck example, what relational property do direct realists claim the stick has?
The relational property of “looking crooked in water,” so we are directly perceiving a crooked looking stick
Who criticises direct realism with the perceptual variation argument?
Russell
In the perceptual variation argument, how do we know that our perceptions vary? Give an example
Because we have different eyes/minds etc
Ex. A shiny brown table with light reflecting off of it could seem white to someone and brown to someone else
