How did Berkeley’s ideas challenge Locke’s distinction between primary and secondary qualities? What did Berkeley mean by the phrase “perception is the only reality”?
According to Locke, the mind has primary and secondary qualities. The primary quality exists in the object that is not debatable. The shape of the building, this quality will be perceived similar by everyone but the color of the building will be dependent on one’s perception. It can change from one mind to another. For example, the tickle of a feather this perception will depend how the mind perceives it. It is not dependent on the object, which is the feather.
For example, he took three glasses, each containing cold, lukewarm and hot water. When the subject immersed its fingers in the cold water and then in the lukewarm water it perceived the lukewarm water to be hot.
However, when the subject immersed its fingers in the hot glass, and then into the lukewarm water it felt cold. These different responses are reported because of difference in perception. The secondary quality depends on our perception and not on the object.
Berkeley and Locke had agreed that knowledge was superficial but disagreed on primary quality. According to him everything has a secondary quality. Everything was dependent, on the perception of the object. He said that the only reality is perception, which one is sure about.
The material substance is one, about which no one can be sure of. He did not deny the fact that in the physical world, real objects existed. He viewed that everything that we see like color is something, which is derived from our own experience that is why perception will be different between different minds.