Assuming that in order to best achieve their goal, individuals adapt their behaviour to the game situation, this paper examines the appropriateness of the Berge behaviour rule and equilibrium as a complement to Nash. We define a Berge equilibrium and explain what it means to play in this fashion. We analyse the rationale of individuals playing in a situational manner, and establish an operational approach that describes the circumstances under which the same individual might play in one fashion versus another.
