Aggressive behaviors and attitudes are investigated first of all from the viewpoint of psychology, sociology, and philosophy. These three disciplines could provide a coherent groundwork for the science on aggression in sport. The science on aggression in sport would be a discipline united by a bond between related issues and a unity of subject, and not by one uniform method. There are two different viewpoints concerning aggression in sport: the cognitive and the ideological. The cognitive viewpoint approaches sports phenomena objectively in order to describe, explain, and compare them—that is, to present the real situation. The ideological viewpoint approaches the subject in an ideological way; that is, it strives for to presenting sport in the most favorable light, while attempting to hide its vices. This viewpoint makes it nearly impossible to diagnose the existing state of affairs, Attitudes towards aggression in sport, while taking into account other criteria, may be divided into the cognitive and the commonsense interpretations. Proponents of the commonsense viewpoint suggest that aggression is a solely negative entity and that it takes place only in the form of emotionally driven aggression meant to do harm. The cognitive interpretation suggests that there exist two forms of aggression in athletic rivalry: emotional aggression aimed at doing harm to an opponent and necessary aggression resulting from the regulations of a given sport. Aggression in sport—considered from the viewpoint of regulations of particular sports—may be either necessary (that is, instrumental) or non-instrumental (that is, potential in the sense that it enables expression of emotions which are not provided for by regulations). Aggressive behavior is necessary when called for by the regulations of a given sport, specifically, among others, combat sports such as boxing, judo, or wrestling. Competitors who avoid fighting and who do not manifest aggressive behaviors in such a field are induced to manifest them and—if this does not bring results—may be punished by referees and, as a last resort, sent off.