3.3 John Locke and the Blank Slate

John Locke (1632–1704) was an English philosopher who played a major role in shaping modern Philosophy. He is considered one of the key figures in empiricismThe idea that knowledge comes from experience., the theory that knowledge comes from experience. Locke’s groundbreaking ideas challenged older theories about knowledge, including those of Descartes.

The Tabula Rasa

As an empiricist, Locke rejected the idea made popular by rationalists that humans are born with innate knowledge or ideas. Instead, Locke argued that when we are born, our minds are like a tabula rasaA blank slate.: a blank slate with nothing written on it, and that all of our knowledge comes from experience. In other words, the mind starts completely empty and gains knowledge as it interacts with the world. 

Locke believed that knowledge is built step by step through experiences and reasoning. 

1. Sensations: These are the first inputs to the blank slate. For example, seeing the color blue or hearing a musical note. This is the raw information that we receive from our senses, such as sight and sound. Sensory experiences provide raw data from the external world.
2. Reflections: These are the second inputs to the blank slate. Once we have a sensory experience, our mind processes them. Reflection involves thinking about these sensations, comparing them, and making judgments. In that way, our mind processes, analyses, and organises the sensory information that it receives.

Sensations give us the content, and reflections give us the understanding. Together, the two processes shape how we build complex ideas such as justice.

Through reflection, we realise that some qualities (primary) are objective, while others (secondary) are subjective. For instance, by comparing experiences, we understand that shape and size exist regardless of perception, but color and taste change depending on the observer.