Professor Senses has devoted her career to studying the differences between people in their perception of color. A tone-deaf person would probably not be able to tell two musical notes apart unless they were very different. Hubel and Wiesel discovered cells in the cat's visual cortex that respond only to very specific stimulus characteristics. As a person walks away from you along the street, the image he casts on your retina gets smaller, yet you see him as staying the same size. Arthur has a brain tumor that is interfering with his ability to process auditory stimuli.
Psychology is empirical.
Psychology evolves in a sociohistorical context. Behavior is determined by multiple causes. Our experience of the world is highly subjective. Jerome got out of bed and began doing calisthenics during REM sleep, probably because he was dreaming about boot camp. Research shows that we are virtually paralyzed in REM sleep.