ABSTRACT
The phrase 'fundamental legal conceptions' is particularly associated with Wesley Newcomb Hohfeld's famous analysis of legal rights. One way of representing the fundamental nature of Hohfeld's conceptions that has proved popular over the years is to utilise the device of a square of opposition. More recently, Daniel O'Reilly has adopted the device of a square of opposition as a way of representing the fundamental character of Hohfeld's conceptions. This chapter provides grounds for recognising a deontic operator, a subordinate position and a dominant position as fundamental legal conceptions. The conventional understanding is that the square of opposition is derived from Aristotle's analysis of how different propositions regarding the application of a predicate to a subject may stand in relation to each other. O'Reilly's use of the square of opposition replaces the predicate with a deontic operator, or more precisely four deontic operators: prescribing, prohibiting, permitting, permitting not.
