Aggression: intentional behaviour aimed at causing either physical or psychological pain. Whether or not the harmful action succeeds in its goal, it is still aggression. Ex: if someone throws a beer bottle at your head, whether or not the bottle misses or hits the person, it is still seen as aggression. Hostile aggression: the act of aggression stemming from feelings of anger and aimed at inflicting pain or injury. Instrumental aggression: aggression as a means to some goal other than causing pain. For example, in a football game, a player will do whatever to thwart his opponent and tackle the ball carrier; it is unintentionally inflicting pain, but doing so for the game. However, if he becomes angry with his opponents and intentionally hurts another player, it is hostile aggression. Sigmund freud theorized that human beings are born with an instinct toward life, which he called (cid:498)eros(cid:499), and a death instinct (cid:498)thanatos(cid:499), which leads to aggressive actions.