Indirect Realism Flashcards
Who are the main proponents of indirect realism?
Russell and Locke
Define sense data.
The information given off by objects in the real external world which can be interpreted by our senses to create a representation of that world.
Summarise indirect realism.
A three part theory which states that we have a mediated perception of reality in which we can interpret sense data but never reach the reality of an object which remains behind a veil of perception.
Define primary qualities.
Properties that are innate to an object and define its nature. They are mind independent, objective, unchanging and often mathematically calculable. Primary qualities include shape, size, volume, mass, density and motion.
Define secondary qualities.
Subjective properties such as colour, smell, taste, sound, and temperature. They are interpretations of an object’s primary qualities that only exist within the mind (eg. colour is just an interpretation of light’s interaction with differently shaped molecules). A secondary quality is simply an object’s ability to invoke a sensation in a perceiver.
How does Berkeley attack the idea of primary and secondary qualities.
He raises examples of the subjectivity of primary qualities:
-Size is relative to the size of the perceiver
-Distance affects size
-Texture appears different when an object is magnified-smooth surfaces can appear craggy under a microscope
-Shape is affected by angle and perspective
-Motion is relative to the speed of our ability to observe it
He concludes that primary qualities are like secondary qualities- they are mind dependent.
What are the two skeptical issues with indirect realism.
If we cannot get beyond the veil of perception to the reality of our perceptions, this opens all our perceptions up to skepticism.
a) We can say nothing at all about the nature of the external world
b) We cannot even assert the existence of the external world as we have no evidence that it exists at all
Explain Russell’s first attempt to rebuff skepticism.
Russell attempts to use the consistency of our perceptions with others to validate our perceptions, but realizes that as we can only learn of other people’s perceptions via sense data, this is begging the question.
Give Russell’s best hypothesis argument in premises.
1) Either sense data is caused by a real external world, or it isn’t
2) I cannot prove either claim to be true
3) Therefore I must treat both as hypotheses
4) The idea that sense data is caused by the real external world is the better hypotheses
5) Therefore sense data is caused by the real external world
Explain Russell’s argument from coherence of perception through time.
Russell argues that the mind independence of the external world can be demonstrated by the fact that objects continue to age when they are unperceived. If you leave an apple out on the table and come back to it a week later, it will have rotted. This suggests it has continued to exist unperceived.
Describe Locke’s argument for a mind independent reality.
Locke refutes skepticism on 2 grounds:
a) We have no choice over our perceptions. In other mind dependent experiences we can control the direction our perception takes. The fact that this is not the case suggests that these perceptions are driven by an external force.
b) Corroboration between our senses. When we have a visual perception of a shape, our tactile perception of that shape supports that and so on.
Explain Locke’s pen and paper analogy.
Locke uses the example of writing on a piece of paper to rebuff skepticism. When we chose to write something down, we can picture the words as they will appear on the page, but we do not perceive this change until we pick up a pen and write. Our intentions match the writing we see on the page. If we ask someone to read what we have written, our visual interpretation of our writing will match our auditory one.
