The world we live in is often taken to be the direct cause of all of our sense experience and this common sense approach is rarely given a second thought. However, upon reflection the experiential process of acquiring and interpreting sense data is complex and still under discussion. John Locke proposed the idea that our minds are born in a state of Tabula Rasa and therefore all knowledge must be gained through experience. Although Locke proposed that are minds are blank at birth he did not succumb to the Naive realist theory that our minds experience the world directly. For Locke, our experiences are more convoluted and involve different qualities to explain the relationship between our minds and the external reality. Inspired by the scientific theories of Robert Boyle, Locke follows from the Corpuscular theory by trying to express external reality in terms of particles, the smallest components of matter. The primary qualities according to Locke are made up of five properties: shape, extension, solidity, motion, number. Secondary properties are dependent on primary qualities and act as a “power” in creating the sense experiences of colour, smell, sound, texture and taste in the mind, thus bridging the gap between mind and body thereby satisfying Locke’s dualistic views. However, the distinction Locke makes comes under attack from many angles. Berkley argues that the distinction is impossible to comprehend and we should therefore refrain from attempting to look behind the view of perception and accept that we can’t refer to things beyond the mental. If Berkley’s rebuttal has understood Locke’s proposal correctly and tenability is dependent on comprehension, the distinction Locke makes between primary and secondary qualities must be deemed untenable.
In order to establish whether the distinction Locke makes is tenable it is important to assess why he proposes the experiential theory.