The Influence Of John Locke On Perception

Philosophers have long reflected on our ideas of perception and reality. Common sense beliefs about perception include that we directly perceive objects and that we perceive objects as they truly are. John Locke, an English philosopher of the 17th century, challenged both of these beliefs. In this paper, I will explain Locke’s reasoning against these beliefs by illustrating his arguments for the primary quality/secondary quality distinction, as well as the difference between primary and secondary qualities and between the quality and the idea of the quality. I will also raise an objection for one of these arguments, as presented in lecture.

First, it is important to distinguish between the quality and the idea of the quality. Locke defines a quality to mean an attribute of an object, while the idea of a quality refers to our mental representation of this attribute. Thus, we only directly perceive our ideas of qualities rather than the qualities themselves and only indirectly perceive the actual qualities through our ideas (page 17). Locke goes as far as to differentiate between types of qualities with what he calls primary qualities and secondary qualities. A primary quality refers to

It is possible to come up with instances in which it appears that changes in the perceiver or the environment can change our ideas of primary qualities. In lecture, for example, the case of a paddle submerged in water was raised. When the paddle is submerged in water, the water may cause it to look bent, resulting in a change in the perception of the primary qualities of both shape and size. This would seem to prove the argument wrong as it demonstrates that the environment and the perceiver can undergo changes that alter the ideas of the primary