PERCEPTION- Locke's primary and secondary quality distinction Flashcards
What was Locke’s definition of Idea
“Whatsoever the mind perceives in itself, or is the immediate object of perception, thought or understanding, that I call idea”
What was Locke’s definition of Qualities
” the power to produce any idea in our mind I call a quality of the subject wherein that power is”
What are primary qualities
he argues that what he calls idea or sense data of certain properties of objects resemble their real properties
What is an example of primary qualities
when I look at a tree my sense data of its size, shape, position and motion correspond accurately with its true size, shape, position and motion
What is an example of secondary qualities
What my sense data isnt accurate with its true properties such as its colour, taste and sound
What does Locke call secondary qualities
The ‘powers’ to produce an idea or sensation within us
What are these powers a consequence of
The movements etc of the ‘insensible parts’ of objects that are not of their microstructures( the primary qualities) which we cannot directly observe
What are the primary qualities in relation to the object
‘Utterly inseparable’- however the object is altered (eg if a grain of wheat is divided) it will still retain some shape, size, position etc even if we cannot see it
Primary qualities are essential to the material object and are retained by the objects whether we r not anyone perceives them
What type of argument is Lockes for primary qualities
An a priori argument based on what we conceive
How can Lockes a priori argument be summarised
P1) if you continually divide an object the parts must retain the primary qualities even when they are too small to be perceived
C) therefore primary qualities must exist mind independently
Summarise Lockes argument about secondary qualities
P1) when we pound an almond we merely change the shape of its parts
P2) but the colour and taste of the almond also change
C) so the change in colour and taste is caused by the change in the shape of the almond parts
What is the Criticism of Lockes PQ/SQ
Locke shows that the qualities can change, but if change is a quality of secondary it would mean that Lockes logic would say that the shape and size of the pieces of the almond are mind dependent.
If we accept that the secondary qualities depend on the texture of the almond this doesn’t show that they are purely mind-dependent.
More rational to conclude that a certain taste, smell and colour are objective properties of an almond
What is the summary of Lockes statement that qualities depend on our sense organs
P1) certain qualities disappear if we block our sense organs
C) so these qualities depend on our sense organs and do not exist in perceived reality
Critical of the sense organ argument
Can’t distinguish between PQ/SQ
When You close your eyes both disappear while you can still handle objects to feel their shapes if we let go of them then those sense experiences cease
PQ have the same qualities as SQ in this regard
Outline the perceptual variation argument
P1) the same water can produce the idea or sense data of cold to one hand and warmth to the other
P2) something can’t be warm and cold at once
C1) therefore the cold or warmth cannot belong to the material object (the water)
C2) so cold and warmth are purely sensations produced in the perceiver
