Accordingly, a proposition is the sense of a context-free declarative sentence. A context-free sentence is one from which all indexical elements have been extruded, including verb tenses. Propositions so construed are a species of abstract object. This will elicit howls of outrage from some, but it is a view that is quite defensible.I.e. proposition in the sense the medievals used it is “context-free declarative sentence”. A proposition in the modern sense is the sense (or ‘meaning’) of a context-free declarative sentence. (The medievals sometimes distinguished between a spoken proposition, i.e. context-free declarative sentence, and a ‘mental proposition’, i.e. the sense of a context-free declarative sentence.
Bill continues with a version of the ‘lazy argument’ for not doing anything, as follows.
1. Either I will be killed tomorrow or I will not.
2. If I will be killed, I will be killed no matter what precautions I take.
3. If I will not be killed, then I will be killed no matter what precautions I neglect.
4. It is pointless to take precautions.
This is a breathtakingly rotten argument. Is it true that I will be killed in France tomorrow, I will be killed even if I take the precaution of not going to France? Surely not. It cannot be true that I will have been killed in France, even though I have not gone to France. The argument is only effective if we believe in truthmakers. For if the proposition ‘I will be killed in France tomorrow’ is true now, then Truthmakerists say it has a truthmaker now, i.e. some state of affairs that ‘makes it’ true. But if the truthmaker exists now, and given that we cannot change the immediate present or the past, we cannot change the truthmaker’s existence. So we cannot change the future, for the truthmaker that exists now makes the future true.
The early Duns Scotus has a nice argument against this which I discussed in a post in 2009. Scotus writes
It must be understood that a proposition about the future can be understood to signify something in the future in two ways. So that the proposition about the future signifies it to be true now that something in the future will have to be true [verum esse habebit] (for example, that ‘you will be white at a’ signifies it now to be in reality so that at time a you will be white). Or it can be understood that it signifies now that you will be white then: not that it signifies that it is now such that then you are going to be white, but that it signifies now that then you will be white. For to signify it to be [the case] now that you will be white at a, signifies more than to signify that you will be white at a.*I take it that “signify it to be [the case] now that you will be white at a” means signifying that a truthmaker exists now for ‘will be white at a’.
*From a translation I made in 2009, which may be different from the corresponding translation (of Aristotle’s Perihermenias) that is now going through the usual process at CUA publications.