" The immediate causes of feelings include (a) the background flow of life processes in our organisms, which are experienced as spontaneous or homeostatic feelings; (b) the emotive responses triggered by processing myriad sensory stimuli such as tastes, smells, tactile, auditory, and visual stimuli, the experience of which is one of the sources of qualia; and (c) the emotive responses resulting from engaging drives (such as hunger or thirst) or motivations (such as lust and play) or emotions, in the more conventional sense of the term, which are action programs activated by confrontation with numerous and sometimes complex situations; examples of emotions include joy, sadness, fear, anger, envy, jealousy, contempt, compassion, and admiration. "

― António R. Damásio , The Strange Order of Things: Life, Feeling, and the Making of Cultures