ABSTRACT
When citizens, collectively or individually, as official agents or as private actors, make decisions having widespread public consequences, people hope that these decisions will be based on serious deliberation rather than upon thoughtless impulse, compulsive need, or careless guess. Yet however deliberative he seeks to be, it is very likely that he will encounter in that environment many problematic situations which demand decision but in which information about key factors is unavailable or rests upon reasoned belief and conjecture rather than upon established knowledge. An ideology is not itself a set of moral commitments or political ideals which are employed to judge events good or bad in the light of their consequences, although one's values do influence his selection of problems and they are psychologically linked to his ideological beliefs. Ideologies are essential to responsible decision-making in conditions of limited empirical control.
