Can't a case be made that ultimately all ideologies are psychological? They all are based on beliefs: in the case of fascism, a belief in the inherent superiority of people who are members of some group; in the case of Liberalism, universal equality and Rights; while Marx was a radical equalitarian (not really a materialist) who did not accept the existence of Rights. The only validation required for any belief is a person's acceptance of it: to accept it is to assert its validity. (That is what separates beliefs--which are assertions of knowledge of a kind--from knowledge pertaining to material existence.) What determines whether a person will accept/reject one belief or another?