In his Tajfel Memorial lecture Gustav Jahoda (1986) proposes that experimental findings infrequently reflect natural laws of human action, but are reflections of cultural conventions. In developing his arguments he finds it useful to criticize a number of my earlier ideas (Gergen, 1982). The present paper demonstrates that this critique is not only misguided, but that if the implications of my earlier work had been properly elaborated neither the argument for cultural convention nor general laws could be adequately sustained. Because of the non-objective character of behavioural interpretation, neither of these positions can be empirically warranted. Their justification is more properly considered in ethical, or ideological terms.