John Locke was a 17th century British philosopher who wanted individuals to use reason to seek truth rather than relying on authorities' pronouncements as to what truth is. He sought to understand the limits of human comprehension with regards to God and the self and believed that innate understanding did not exist, with the mind instead existing as a "tabula rasa" or clean slate at birth.
The Tabula Rasa
In his master work, "Essay Concerning Human Understanding," Locke refutes ideas proposed by Réné Descartes that human beings know certain concepts innately. Locke believed the human mind was what he called a "tabula rasa," which is Latin for "clean sheet of paper." He believed infants know nothing when they are born, and that all the ideas humans develop come from experience.
Sensation and Reflection
Locke believed there were two types of experience: external and internal. He called external experience "sensation," referring to human beings' interaction with objects in the real world, including the color, motion and number of such objects. He referred to internal experience as "reflection," referring to acts of the mind such as knowing, believing, remembering and doubting.
Simplicity and Complexity
Locke proposed that all sensation and reflection fell into the categories of being either simple of complex. A simple idea is one which centers on one element such as, say, whiteness. A complex idea is one which combines several simple elements, as an apple contains the simple concepts of whiteness, redness and roundness.