Aggression and prosocial behaviour appear to be subject to very similar conditions, and processes. These two are discussed and compared along with correlations investigated by temperament theorists. The relevance of the Sherif (1953) experiment is examined, and used to illustrate how those with prosocial qualities and personalities can act in an aggressive manner at the same time, thereby bringing the idea of a continuum into doubt. The issues raised in the Sherif experiment are then re-applied to global instances of prosocial and aggressive behaviour.Prosocial behaviour is described by Eisenberg (1988) as 'voluntary behaviour intended to benefit another regardless of motive', while aggression is viewed as 'behaviour intended to harm others'. Indeed the definitions would suggest that the two be opposed yet related. Yet the infinite array of situations in which people behave in these two particular ways and the differing extents to which they do so have made it difficult to discern the exact nature and, in fact, the very existence of, the link between them. Both require a degree of social perception and serve an extremely important purpose in the process of natural selection. The norm of reciprocity can cause us to behave in both negative and positive ways towards our neighbours. Entirely altruistic behaviour is rare and egoistic motivations often underlie actions which cause the betterment of others lives. Just as a chimpanzee will groom another's body with the expectation of receiving the same service in return, so do we help others in the hope of being rewarded in some fashion, be it recognition, the avoidance of guilt or the long term well being of the group to which the helper belongs. Even, with the prospective advantages associated with prosocial behaviour, we are reluctant to act if the costs to ourselves are too great. The criteria for aggressive acts tend to mirror those of prosocial behaviour. Violent situations...
