The two categories of »fiction« and »non-fiction« are most often conceived of – and treated as – disjointed and separate, not only in common sense but also in literary studies. This does not adequately reflect, however, the developmental trajectory of the non-fiction genre over the course of the twentieth century. After all, the popularization of expert knowledge has increasingly been effected with the help of narrative strategies which raise one crucial question: Just how much fiction can the factual nature – the dependence on facts – of non-fiction tolerate? However, as the more precise definition of the pertinent term, »fiction«, indicates, a distinction must be made between »fictionality«, on the one hand, and »fictivity«, on the other. »Fictionality«, that is to say, refers to narrative strategies analogous to those of fiction , but which relate to historical facts. »Fictivity«, by contrast, refers to the representation of fictitious content . More precisely, then, the question is this: Just what degree of fictivity can the factuality of non-fiction writing tolerate? Since this question cannot be answered constructively from a quantitative but only from a qualitative point of view, we are faced with the ultimately crucial question: Just what kind of fictivity can the factuality of non-fiction tolerate? In trying to answer that question, it seems advisable to start from the structure of deductive-nomological explanation, in which a given phenomenon – the explanandum – is explained by deducing its description from regularities plus the antecedent conditions contained in them (the explanans ). In the case of historical explanation, in particular, historical facts most often form the explanandum, while the antecedent conditions of the potentially explanatory regularity (i. e., of the explanans) are not historically documented. Even more specifically, the genre of biography presents a paradigmatic case of such historical explanations falling within the purview of literary studies as well. Not uncommonly, attempts to arrive at a coherent, psychologically convincing biographical portrayal are met with the problem that historically documented life events can be explained – as to their genesis or »coming about« – only by reference to ultimately fictitious – or, to take up the distinction introduced above, to ultimately fictive – assumptions regarding antecedent conditions. Literary biography may, therefore, be said to realize the desired combination of fictivity and factuality in the best possible way: namely, as fictivity in the service of factuality. To find a paradigmatic example of such a combination, one need look no further than the biography of the German chemist Clara Immerwahr, wife of the professor of chemistry, Dr. Fritz Haber, who during the First World War was in charge of German efforts to develop and deploy chemical combat agents such as poison gases. Clara Immerwahr demonstrably saw her husband’s work as a perversion of science but was completely isolated and powerless in her protest against it. Her suicide after the German gas attacks at Ypres in April and May 1915 may therefore be understood as a final and ultimate protest (attempt). There is no clear evidence for this, however, since Immerwahr’s farewell letters no longer exist. Accordingly, the path leading towards her decision to end her life has to be reconstructed using fictive assumptions (about decisive life events). This implies the following, central hypothesis: »Once a person breaks away from a religiously motivated rejection of suicide as an inadmissible interference in God’s plan, that person will, in a situation of hopeless, existential, despair, commit suicide.« In the example of a literary biography presented here, Immerwahr’s reaction to the papal encyclical of 1910 is posited as a fictive antecedent condition, for which no historical record exists. In particular, this involves the question whether Immerwahr was prompted by that experience to establish, in her own mind, the precedence of a scientific-humanistic ethos over any kind of religious ideology. That she did come to rank a scientist’s morality of a shared humanity more highly than religious dogma – particularly where self-determination over one’s own life (and the end of one’s own life) was concerned –, is, however, a highly probable developmental condition of her life story, considering its actual culmination in a highly demonstrative suicide. On the basis of this exemplary piece of biographical writing, the connection of fictivity and factuality may be considered in terms of its fundamental structures, and may be revealed as really a case of fictivity in the service of factuality. In fact, we are looking at an explanation of the »how it was possible that« type, in which the explanandum is a confirmed (historical) fact, while the antecedent condition of the explanatory regularity can only be postulated as a psychologically plausible, hermeneutically intelligible life event. It is this combination of factual effects (hence explained) and fictive conditions (thus explaining), or, otherwise put, of historical factuality and (psychologically) probable fictivity, which is meant to be captured by the term »real fiction«. Biography as a genre is particularly suitable for the elaboration of this concept of »real fiction«, because it has been seen as »fundamentally caught between facts and fiction« – between factuality and fictivity – for quite some time now. To justify the introduction of a new genre, however, the level of detail chosen must be such that it, on the one hand, allows us to apprehend the differences, in terms of literary theory, between this new model and other, established models of factuality, while at the same time giving a nuanced, structured account – one that meets the requirements of the philosophy of science– of how precisely fictivity might be said to be »in the service of factuality«. With regard to genre concepts already established in literary theory, one will have to consider the historical novel and the writing of the New Objectivity movement as well as documentary literature. In the case of the historical novel, writers’ »fictivity leeway« is much greater, since there is no requirement for a strict coherence with concrete factual explananda. As an antithesis to this, consider the writing of the New Objectivists, which is characterised by a predominance of factuality which is accompanied by a wholesale – if overgeneralised – rejection of aesthetic concerns and the demand for an unreserved critique of society and ideology. This same anti-ideological impulse also characterises documentary literature, in which the preferred narrative strategies are even fewer (being restricted to the modes of reportage, montage, etc.). The genre of »real fiction«, by contrast, is much more open and flexible, both in terms of (theoretical) content and narrative strategies. In return, however, it places significantly higher demands on the structural relation between fiction and factuality, insofar as an explanation of relevant historical facts has to be given. Thus, the concept of »real fiction« is characterised by a combination of openness (regarding its possible topics and content) with a formally concise explanatory structure. This is how »real fiction« particularizes the fictive in the service of the factual. In the end, »real fiction« can be explicated as a form of narrative explanation in the sense proposed by Danto. It is concerned with the historical explanation of developments – and in the case of biography, more specifically, with the explanatory reconstruction of a life story in ontogenetic terms. Thus, the reconstruction of fictive life events in the form of a narrative does indeed provide a causal explanation, but it does so employing narrative strategies. This permits an epistemological differentiation between »real fiction« and both explanatory narration and thought experiments, at the same time effecting a marked pragmatization (through recourse to the criterion of relevance) and a heightened flexibility of narrative strategies available. If one conceives of the combination of fictivity and narration as the source of literariness, we are ultimately confronted with a synthesis of (literary) art and science, of scientificity and literariness. Being, in the memorable phrase of Wilhelm Dilthey, a wissenschaftliches Kunstwerk (i. e., a »scientific« or »scholarly work of art«), »real fiction« is both: literature striving for the highest standards of scholarship – and scholarship given a literary form.