Some novelists take as part of their task the description and evocation of certain social realities. James Baldwin captured one slice of African-American life in the 1950s and 60s. Tim O'Brien captured aspects of infantry life in Vietnam in The Things They Carried. And Tolstoy caught much about social attitudes and relations in elite Russia at a certain time and place. We could interpret these sorts of novels "realistically" and ask a range of questions about them: how accurate are they? Do they leave out important aspects of the picture? And what was the epistemic location of the author, such that he/she could claim to observe and portray accurately?
If we take this function of literature seriously, then it is natural to ask how this creative act relates to various areas of the social sciences. Does the knowledge offered by Baldwin complement the work of sociologists and historians of race in America? And, for that matter, can the realistically-minded novelist find valuable synergy in the research of historians and sociologists?
These questions are taken especially seriously by critics who are developing the framework of "critical realism", including especially Satya Mohanty. Particularly valuable is Identity Politics Reconsidered (Future of Minority Studies), edited by Linda Alcoff, Satya Mohanty and Michael Hames-Garcia. The topic is a core concern for the Future of Minority Studies project (link).
So, what about it? Can a work of fiction have realistic, referential content? Is a novel sometimes an empirical statement? Can a fictional character truthfully represent aspect of what it is like to be black in America, South Asian in Manchester, or gay in a suburban Illinois high school? For that matter, can a novel be faulted for "getting it wrong" -- for example, for representing an American Muslim as being completely oblivious to issues of racism? Or is "right" and "wrong" out of place when it comes to evaluating the relationship between a novel and the world?
Here is one possible answer: fiction is always fiction, and normally does not have empirical validity. If we want to make empirical statements about social relations, class attitudes, or typical social values of specific groups, we need to do so based on valid methods of social research: surveys, focus groups, interviews, and observations of behavior. And we need to analyze the data we collect according to valid methods of aggregation and inference. That is what is required in order to arrive at knowledge about the social world.
Another very different response goes along these lines. Novelists are sometimes skilled social observers, and some of these are also skilled "painters" or evokers of what they have seen. A great novelist can pull together his/her many insights and observations into a powerful description of a fictional world or experience that captures an important sociological truth about the society depicted. So these novelists do in fact gain knowledge of social life through observation, and they represent that knowledge through the fiction they produce. Both parts of this epistemic process are subject to criticism; but both are valid knowledge practices.
According to the second view, readers have the possibility of gaining real knowledge about the social world through the novel. Seen in this way, a novelist is somewhat akin to an ethnographer, trying to make sense of a complex system of behaviors and meanings and expressing his/her findings in a way that is truthful to the social reality observed.
It seems that one would have to be a pretty narrow-minded epistemologist to hold that there is only one kind of knowledge, and that literature necessarily falls outside its bounds. This might have been credible when the program of logical empiricism still seemed possible -- that there are observations that can be unambiguously arrived at, and that theories are evaluated through a specific logic of confirmation marshaling a domain of observations in support of hypothetical statements. But this epistemology doesn't work well even in the sciences. And within the framework of an anti-foundationalist epistemology, it seems reasonable enough to believe that literature has the potential of revealing important aspects of the social world.
This brings us back to the question of linkage between literature and the social sciences. If we think that Platoon or The Things They Carried express some important truth about the nature of the experience of that war for American soldiers, this suggests the possibility of framing other sorts of social-science investigations to probe the extent and variation of these characteristics on the ground. In other words, there is a simple kind of synergy that can exist between novelists, sociologists, and historians, when it comes to framing interpretations and explanations of a complex social reality, and designing further empirical studies to evaluate and qualify these findings.