Welcome to the class blog for Philosophy 3650/7160: Contemporary Metaphysics I: The Metaphysics of Propositions. This blog is for course updates and discussion.
This seminar will focus on the metaphysics of so-called abstract objects, propositions in particular. Propositions are supposed to be shareable objects of attitudes that are truth-apt, or capable of being true or false.
By 'attitudes' we mean propositional attitudes: belief, knowledge, desire, etc. As a rough guide, attitudes that involve 'that'-clauses indicate attitudes toward propositions. So for instance, if I believe that the children are the future, then if there is a thing that I believe, that thing is a proposition.
By 'shareable' we mean that more than one person can have an attitude toward that proposition. Your believing something is not something someone else can do; your experiencing something is private. But the proposition that the children are the future is not private; both of us can believe it.
To be truth-apt is to be the sort of thing that can be true or false. Chairs are not truth-apt; sentences and propositions are. It is generally held that propositions are the primary bearers of truth or falsity; a sentence that is true or false is so because the proposition it semantically encodes is true or false.
Why think there are or are not propositions? Here's what McGrath calls "the Metaphysics 101 Argument":
1. With respect to any belief, there is what is believed and the believing of it, and these are distinct.
2. What is believed is something that may be rejected, denied, disbelieved, etc. by multiple subjects, and is something that may be true or false.
3. There are beliefs.
4. So, there are propositions (i.e, sharable objects of the attitudes and bearers of truth-values).
Is the Metaphysics 101 argument any good?
What reasons are there to believe there are no propositions? For that, see Dorr's article to the right along with the rest of McGrath's article.
Are there other compelling reasons to think there are abstract objects? For that, see Swoyer's article, "Abstract Objects", that Dorr is responding to.
But first, we should think more about just what propositions are supposed to be so we can carefully distinguish them from their neighbors and keep our quarry in clear sight. For that, see Cartwright's magnificent article, "Propositions".