36: On the Local Proposition
On the Local Proposition so that a proposition like 'A creature is created when God creates' means this: 'If God creates, a creature is created'.
Hence, the proposition 'Socrates exists while he exists' or 'Socrates is moving while he is running' is not necessary, but can be false. Nevertheless, some take such temporal propositions as conditional propositions—and those conditional propositions are true.
Similarly, for a temporal proposition to be impossible it is not required that some part be impossible. Rather, it is sufficient that the parts be incompossible. Thus, this is impossible: 'God creates while he does not create'. For the parts are incompossible. However, if the temporal proposition in question signifies that the propositions are true for different times, then in order for it to be impossible it is sufficient that the parts be interchangeable—so that one cannot be true without the other being true, and vice versa.
From what has been said it is clear what is required in order for a temporal proposition to be possible or contingent. It is also clear from what has been said that there is a valid consequence from a temporal proposition to one of its parts—but not conversely. Similarly, a conjunctive proposition follows from a temporal proposition—but not conversely. For this does not follow:
'Adam existed and Noah existed; therefore Adam existed when Noah existed'. Nor does this follow: 'Jacob existed and Esau existed; therefore Jacob existed when Esau existed'.
36: On the Local Proposition A hypothetical proposition can be called a local proposition when it is composed of two or more categoricals joined by an adverb of place or some equivalent—as in 'An accident is where its subject is' and 'Christ suffered where he preached'.
For the truth of such a hypothetical proposition it is required