Propositional Variable Set

References

(Goldrei, 2005) ⇒ Derek Goldrei. (2005). “Propositional and Predicate Calculus: A Model of Argument." Springer.
- QUOTE: With considerations like these in mind, we shall define our formal statements as follows. First we shall specify the formal language, that is, the symbols from which strings can be formed. We shall always allow brackets - these will be needed to avoid ambiguity. We shall specify a set [math]\displaystyle{ P }[/math] of basic statements, called propositional variables. From these we can build more complex statements by joining statements together using brackets and symbols in a set [math]\displaystyle{ S }[/math] of connectives, which are going to represents ways of connecting statements to each other, like V for 'or' and other symbols mentioned earlier. ...
- QUOTE: Convention for variables: We shall normally use individual lower case letters like p, q, r, s, ... and subscripted letters like p₀,p₁,p₂,...p_n,... for our propositional variables. Distinct letters or subscripts give us distinct symbols. When we don't specific the set [math]\displaystyle{ P }[/math] of propositional variables in a precise way, we shall use p,q,r and so on to represent different members of the set.