Prescription, Description, Ideology

While the scope of a Prescription may be no more than particular, that of a Description, i. e. of an objective proposition, is universal.  Thus, the casting of a Prescription as a Description can exemplify what Marx calls 'Ideology', in which special interests are codified and entrenched as 'truths'.  For example, in Capitalism, the prescription "One should always act in one's self-interest exclusively" is converted to the Psychological description "One inherently always acts in one's self-interest exclusively", thereby validating the good fortune of those who benefit from the system, and, thus, reinforcing their power in it.  So, detecting that distinction is significant to his potentially revolutionary exposure of Capitalist Ideology.