Final answer:
John Locke theorized that the mind starts as a blank slate, or 'tabula rasa', and knowledge is acquired exclusively through experience. Humans are born with no pre-existing knowledge, and sensory experiences combined with reflection are the foundations for all learning.
Step-by-step explanation:
According to John Locke, our mind begins as a "blank slate" and all knowledge comes from "experience". Locke's philosophy, known as empiricism, posits that at birth, humans possess no innate knowledge, concepts, or morals. Instead, our minds are tabula rasa, empty and ready to be filled with knowledge through sensory experiences and reflection. This stands in stark contrast to the idea of innate ideas presented by rationalists, such as Plato, who believed that knowledge is a matter of recollecting what the soul already knows from the realm of forms.
In his 1690 work, 'An Essay Concerning Human Understanding', Locke explains that humans learn only from experience, and this experience comes through sensation and reflection, leading to simple and then complex ideas. He effectively argued against the pre-existing notion of pre-installed knowledge, revolutionizing the understanding of how knowledge is acquired and organized in the mind.