Physical stimulation of the sensory organs does not produce...

Physical stimulation of the sensory organs does not produce ideas unless the mind is attentive. [Essay II ix 1-4] Here Locke tilts to a significant feature of our sensory experience. Although we are almost constantly bombarded by physical stimuli-any one of which will, in the ordinary course of things, produce in our minds a particular sensory idea-we never perceive all of them and sometimes exercise deliberate control over which ones we do perceive.

Attention, choice, and judgment can all influence the operation of the officially passive faculty of perception. [Essay II ix 7-8] Another of our cognitive capacities is the ability to retain ideas in the mind over time, either in continuous contemplation or in recollection of ideas after a period of inattention. Although he naturally relied upon the spatial metaphor of memory as a "Store-house" or "Repository" of ideas,…