Strong vs. Weak Terminology (1)
The relative notion of “stronger” vs. “weaker” formulas is formally defined in terms of logical implication:
P1 is said to be stronger than P2, and P2 weaker than P1, iff P1 implies P2 (P2 is true everywhere that P1 is true) and they are not equal (P2 is also true for at least one system ‘state’* where P1 is false).
Therefore , we can legitimately speak of True as the U, and False as the U, of all possible assertions, or predicates, about object values.
* ‘State’ means the values of all relevant data items and objects.