S: (n) instinct, inherent aptitude (inborn pattern of behavior often responsive to specific stimuli) "the spawning instinct in salmon"; "altruistic instincts in social animals"
S: (n) id ((psychoanalysis) primitive instincts and energies underlying all psychic activity)
S: (n) mind, head, brain, psyche, nous (that which is responsible for one's thoughts, feelings, and conscious brain functions; the seat of the faculty of reason) "his mind wandered"; "I couldn't get his words out of my head"
S: (n) noddle (an informal British expression for head or mind) "use your noddle"
S: (n) tabula rasa (a young mind not yet affected by experience (according to John Locke))