It's a common view in contemporary philosophy of language that the act of assertion has some special link with truth. A common view is that this is through some norm of assertion which is violated if assertion is detached from truth. There are different such norms proposed -- perhaps the norm is that we should only assert what is true, or that we should only assert what we reasonably believe to be true, or that we should only assert what we know to be true. It's also fairly commonly the case that people want to take 'truth' here as a specific kind of thing. For instance, is the following true?
Sherlock Holmes lives on Baker Street.The usual assumption in these kinds of discussion is that it is really not. But we assert things with fictional presuppositions all the time, and we don't normally have any problem with this. As I've noted before, I seriously doubt that any of the proposed norms can account for all the things we really need assertion to do. But even if that were not so, it seems to me to be quite obvious that any account of the truth of an assertion can treat 'truth' as univocal in all cases. There is a perfectly straightforward sense in which it is true that Sherlock Holmes lives on Baker Street, and no reason to hold that this is merely metaphorical or that it is a shorthand for a more elaborate and indirect kind of truth. If I ask where Sherlock Holmes lives, there are many situations in which it would be flat-out wrong to deny that he lives on Baker Street. It is true that Sherlock Holmes lives on Baker Street; it is true that Kryptonians like Superman are psychokinetics; it is true that Mr. Darcy proposes to Elizabeth; it is true that Eustace became a dragon. And there is no problem with saying so, because while different cases of 'true' are related to each other, there is no reason whatsoever to think that they are all the same, or that true in a story is somehow not really true at all. To be sure, there are many cases in which true in a story would not be the right kind of 'true' for whatever we are doing; but as anybody knows from those tiresome hyperliteralists who cannot enjoy a story for its own sake, assuming that 'true' in a nonfictional sense (for instance, true insofar as our best scientific theories suggest) is always necessarily relevant is also an intellectual defect. Nor does this cause any problems for logical reasoning at all, as long as you aren't unreasonably shifting the sense of 'true' in the middle of your argument.
One of the recurring problems of much philosophy of language is the attempt to overload linguistic acts with special significance in order to get some solution to some problem or other. We see this in some of the elaborate epicycle-ridden systems people develop with respect to the paradox of fiction, merely in order to deny that we can have emotional attachments to fictional characters, on the ground that they do not exist. But whether a fictional character exists doesn't change anything about the telling of a story itself; if you tell the same story in a situation in which people think the character exists, in a situation in which people think the character doesn't exist, and in a third situation in which people are unsure whether the character exists or not, nothing would have to change in how the storytelling itself works on us. If there were a major difference, we would have reason to say that we are never emotionally responding to the storytelling itself. There is no difference between describing a fictional character and describing a real person; the bare act of description is not so loaded with metaphysics that it can distinguish the two, and if there is a difference in our emotional responses to the two cases, it would have to depend on things that are not particularly relevant to our responses to description, whether what is described exists or not. And likewise it's an error to think that assertion as such has much to do with a specific metaphysics of truth; we may respond to it differently depending on some metaphysical view, but nothing about assertion itself is affected by any of these things. Why would it be?
When we look at the full panoply of assertions we make -- and, indeed, reasonably make -- there seems very little reason to think that assertion, simply considered as such, always has to be concerned with truth; and even when it is concerned with truth, there seems very little reason to think that it will always be concerned with truth in exactly the same way. It's often noted that we criticize false assertions as improper; but we don't actually seem to criticize false assertions as being in any way defective as assertions -- we criticize them for being morally or practically inappropriate in a context. Truth, and whatever kind of truth is relevant in a given case, is important for assertion for moral and practical reasons that have to do with the aims of reason. But this is an indirect importance; if assertion is detached from truth, or from a specific kind of truth, it still works perfectly well as an assertion.
If this is the case, as I think it is, then a common philosophical assumption -- that you can learn something about truth by investigating assertion itself -- is not true. You might learn something by investigating particular kinds of assertions in particular kinds of cases, but for that to be done you would already need to know enough about truth to select out the kinds of assertions and kinds of contexts to study. From assertion itself you will learn nothing much about truth, just as you will learn nothing much about real existence or fictional existence from description, and nothing much about real relations among events from narration, despite the fact that we can and do use all of these acts to talk about all of these things.
Various Links of Interest
* Vaneesa Cook, Why divine immanence mattered for the Civil Rights struggle
* Jessica Murdoch, On the Relationship Between Sanctity and Knowledge: Holiness as an Epistemological Criterion in St. Thomas
* Kris McDaniel, A Philosophical Model of the Distinction between Appearances and Things in Themselves (PDF link a bit more than halfway down the page under "History of Philosophy")
* Working Off Yesterday's Technology at "DarwinCatholic"
* And MrsD recently took up the challenge of writing a story that has all the standard tropes of a Hallmark Christmas movie while giving them an occasionally different twist: Christmas in Luxembourg, Ohio.
* Scott Alexander has a nice review of Kuhn's The Structure Of Scientific Revolutions, one that (thankfully) avoids the usual mistakes people make about Kuhn. There's more that might be said on a few issues, of course. For instance, there is, in principle, no difficulty with finding the paradigms for a science, since strictly speaking you just look in the textbooks: the paradigms are the examples that keep being used to teach the theory. But it was recognized very soon after the book was written that Kuhn sometimes uses 'paradigm' in this sense, sometimes for a family of such examples, sometimes for central features of such examples, sometimes for concepts used in them, sometimes for methods exemplified by them, sometimes metonymically for the theory or for the general view in which the paradigm is seen as plausible, etc. And as David Chapman notes in the comments, the historical location of the work, published in 1962, is quite important for understanding it; logical positivism, once so impressive-seeming, was in its late stages of collapse, but its influence was still everywhere (particularly in the obsessive interest in theory and the tendency to treat physics as the paradigmatic science). While people had taken a history-of-science approach to discussing science before, Kuhn's discussion came at a time during which a lot of people were particularly willing to listen to alternatives to abstract discussions of different formal and semi-formal systems for modeling the process of theory disconfirmation and falsification. It gave them a reason to consider both actual history and messy proposals that could not be captured in a logical system. That Kuhn is often vague and ambiguous at important points arguably was part of what made the work a success -- different people could take him in different ways; that's pretty much what happened, of course, sometimes to Kuhn's exasperation.
I think you can argue that Structure is in some ways to twentieth-century philosophy of science what Richard Whately's Logic was to the field of logic in the nineteenth century. Whately did come up with some interesting things on his own, but his real importance was that he gave a large number of people a new and interesting starting point, and those people did yet more new things with it, to the considerable benefit of the field. So also with Kuhn: his primary importance lies in having shaken things up at the right time.
C. S. Lewis, The Chronicles of Narnia
Augustine, Against the Academicians and The Teacher
Catarina Dutilh Novaes, Formalizing Medieval Logical Theories