Debate Discussion: "The content of belief is propositional". I may be way out of my depth here, but these are my initial thoughts. I suppose part of this depends on how you define "content", depending on the definition of a technical term, which by virtue of being technical , are subject to fitting a certain framework of understanding. Thus "content" can be defined as being in the head, in our statements, or in the world. Let's bracket the definition of "content", and see what makes most sense.
I don't see why content need be attached to anything external to the creature using the term, so talking about content in the world can be ruled out, we give/provide content, not the world. Of course, what's in the world helps guide what we say about it, but it's not essential to the meaning or significance of the term. It's of course not even necessary for there to be a world out there to even talk about content. We could be brain in vats. Of course, this is extremely unlikely, but raising the scenario serves as an illustration of not needing content to be "out there".
Now, do we want to say that content is found in the statements we say out loud, when put in a propositional manner? Suppose I see a dog running towards me, having escaped its owner's leash. I'd say "This dog is racing towards me", thus the content of the statement can be said to be given in the proposition. But is it necessarily so? Must content be said out loud, or even said to oneself in a propositional manner? It's very doubtful.
In fact, if we look at the world at attempt to do some very basic phenomenology we see that experience vastly outstrips my way of talking about it. So in the case of the dog, there is also the background of the owner being careless, of grass looking beautiful in the sunlight, I can also point to my physiology and notice my adrenaline pumping. The dog probably interrupted me from my train of thought, and so forth. Of course this exercise can go on forever, as I try to verbalize my experiences. But it's clear that the whole complexity of the situation cannot be grasped by a simple proposition. There's also more to say about the nature of thought and language, which are extremely complex, but this can be put aside. The content found in my expression is but a small portion of the total content I experience. Henceforth, content is not necessarily propositional in nature.
What's left then? Well, we can attempt to encapsulate the term content in such a manner that most of these considerations do not apply to the term, but this does not mean that the things mentioned aren't real phenomena that shape the content I experience. What must be true of content? Absent anything else, content is internal to the user, and seems to be an operation of the mind/brain that seeks to concretize the totality of my experience in a way that is communicable through words. But there are many other way to express content too: gestures, moods, paintings etc.
So no, content is not necessarily propositional, though it can be defined in such a manner, if one chooses to do so, but I don't see what's gained by doing this.