Locke opens the chapter by confirming the thesis of the previous book: innate knowledge is nonexistent. He then proposes that the mind is a blank sheet of paper. Experience is the key to filling this sheet of paper with thoughts. Sensation presses ideas upon the mind. The mind then undergoes a second process of reflection upon the ideas, which translates to “perception, thinking, doubting, believing, reasoning, knowing, willing, and all the different actings of our own minds” (96). Locke argues that all knowledge comes through one or both processes: sensation and reflection. Attention is the key to moving from one process to the other. A person may see a clock every day, for example, and understand it as an object and symbol. Only by applying attention, however, does the person understand how to tell time.

Many believe that the mind, or the soul, is continually intaking information and reflecting, but Locke suggests that thinking happens only when someone is awake and applying attention. Knowledge requires intentional thinking, because it intrinsically connects with consciousness, which is “the perception of what passes in a human’s own mind” (105). Only awareness can bring greater understanding.