A. Soames brings up a pretty interesting objection to propositions:
1. According to the Frege-Russell view, propositions are the meanings we assign to sentences, formulas and the like, when we interpret them.
2. So it makes no sense to say that propositions have meanings or get interpreted by us. (from 1)
Soames concludes from this misunderstanding that:
3. The Frege-Russell view has a confused discussion of "the unity of the proposition" which makes it impossible to ask the question "What makes propositions representational, and hence capable of being used to interpret sentences and provide their meanings?" because this question violated a fundamental feature of what they took propositions to be.
And this has the result that:
4. If by 'proposition' we mean what Frege and Russell meant, then there are no propositions. (from 3)
But given that there are propositions, the Frege-Russell view must be wrong.
B. Soames offers an alternative way of thinking of propositions as the meanings of sentences, bearers of truth value and objects of attitude:
5. Propositions are structured entities, the constituents of which are objects and properties.
6. To say that certain constituents make up a complex is to say that, in it, the constituents stand in certain relations to one another.
7. So a proposition (the complex) is, in effect, the standing of objects and properties (the constituents) in those relations. (from 5 - 6)
For our discussion here, Soames says that we need no further discussion of details here. What these relations are, of course, will depend on the specific abstract structures we take propositions to be.
C. Soames gives an example:
8. A is different than B.
(8) expresses a proposition which is a complex in which a, b and the difference relation stand in a certain relation R.
Given Soames' view, we can see that a's and b's standing in R to difference represents a as being different from b because of the interpretation we place on R, and thereby on the structure as a whole.
This means that our use of R is such that for a and b to stand in R to difference is for us to take the proposition as representing a as different from b.
We can think of propositions as functioning as something like maps:
Imagine a map with two dots. One is labeled "Winnipeg" and one is labeled "Calgary". The "Calgary" dot is to the left of the "Winnnipeg" dot. This represents Calgary as being to the west of Winnipeg, and Winnipeg as being to the east of Calgary. The dots are 13.28 centimeters apart. This represents that Winnipeg and Calgary are 1328 kilometers apart.
How does the map represent? It represents Calgary as being 1328 kilometers to the west of Winnipeg, in part, because of the interpretation we give to the relation being 13.28 centimeters and to the left of on the map.
A proposition, like a map, is something we interpret. We interpret the propositional relation R, in interpreting the complex in which a and b stand in R to difference.
D. The major conclusion I draw from Soames is this insight:
So while Russell's multiple-relation theory of judgement takes the role of agents to be crucial in unifying the constituents of judgements, we now have reason to take agents to be crucial in endowing propositions with the representational properties that allow them to serve as objects of judgement, and other attitudes.
I am reminded of a (surprise!) Sellarsean idea here: for representations we need representers, representings and represent-eds. Or, to say consistent with Soames, mapers, mapings and map-eds. That there might ever be mapings, and thereby map-eds, without mapers strikes me as preposterous.
I see the issue of models and commentaries useful here as well. Consider:
This model, say, could represent anything. It seems that it certainly needs someone to interpret it for it to mean anything. I do not understand how this map could map anything without a mapper!
But what commentary should be provided? Perhaps it means that if you want to go to Winnipeg, you should go north-by-north east. To go to Brandon north-by-north west. Maybe. Perhaps it means that you are currently in between Winnipeg and Brandon and there are roads going in those directions. Maybe. Perhaps it means that Winnipeg is awesome and Brandon is sucky. Maybe.
I suppose that there are natural readings and unnatural ones, in the sense that some possibilities seem more intuitively plausible than others. I doubt (9) means that Hitler was German and that sandwiches involve bread. But I suppose, if we thought we should interpret it that way, it may well do so.
Wittgenstein complained of Moore and Russell that "they only ever look at the logical form of words, and never the uses of those forms." It seems like an interesting point to note. How could we merely study the logical form of (9) and understanding anything at all about it? It seems that we must take into account how (9) is being used.
I presume we do not need explicit rules of interpretation or commentaries, but that we only need to know how to read sentences or maps in order to know how to interpret them pretty well. We just need, as it were, some simple map-reading skills to be mappers. Then we can read into maps what they are about. It seems that if I show you a map of Winnipeg or tell you the proposition that Frege is bearded, you look past the map itself or the proposition itself, and instead you attention is drawn toward what is represented, i.e. Winnipeg and Frege.
So I think we answer the question: "What makes propositions representational, and hence capable of being used to interpret sentences and provide their meanings?" by noting the need of representers, mappers and interpreters for there to be representations, maps, and interpretations and represent-eds, map-eds, and interpret-eds.