"The word realism has one meaning in logic, where its opposite is nominalism, and another in metaphysics, where its opposite is idealism."-- C.S. Lewis, AN EXPERIMENT IN CRITICISM, "On Realisms."
I speculate that Jung simply mentions this interesting formula because his concern in PSYCHOLOGICAL TYPES is with finding a "middle ground" between the extremes of what he terms "nominalism" and "realism," which he uses as exemplars of his concepts of the "extravert" and the "introvert" respectively.-- AFFECTIVE EFFECTS.
Though I was satisfied with the answer I gave Charles Reece regarding his overly limited definition of the term "realism," Lewis' quote is the sort of thing I would have liked to have pulled out as a quick rebuttal. On the whole when I've used the term "realism" in terms like "thematic realism," or the related term "verisimilitude," my usage generally relates more to what Lewis calls "metaphysics" rather than to the realm of propositional logic to which Lewis refers, and to which Reece may have been referring.
In PSYCHOLOGICAL TYPES Jung also uses "realism" in both senses, though in the above quote his "realism" belongs to the domain of logic, and is meant to signify the domain of the introvert, for whom:
"the idea of the ego is the continuous and dominant note of consciousness, and its antithesis for him is relatedness or proneness to affect." (p. 90)
The extravert, in contrast, lines up with the logical schema of nominalism:
"For the extravert, on the contrary, the accent lies more on the continuity of his relation to the object and less on the idea of the ego."
A page later Jung formulates this difference in "accent" into a figurative religious attitude:
"[The introvert's] god, his highest value, is the abstraction and conservation of the ego. For the extravert, on the contrary, the god is the experience of the object, complete immersion in reality..."
Jung's well-known distinction between his formulation of the "introvert/extrovert" dynamic interests me in that it also applies well to the structure of literary "focal presences," even though Jung's only application of the theory to literature in this book is to cross-compare the psychological outlooks of famous authors like Goethe and Schiller. I suggest that the distinction between a psyche being "ego-oriented" or "affect-oriented" also applies to narratives.
In FOCAL GROUPINGS: RESOURCE, I said:
For [Dwight V] Swain, the "focal character" is the character through which the reader perceives these reactions, and initially Swain seems to be talking about the commonplace notion of what is called variously the "protagonist," the "main character," or the "viewpoint character." However, Swain soon departs from this identification:
"Does this mean that the term 'focal character' is a synonym for 'hero?' Not unless Sammy Glick is a hero in Budd Schulberg's WHAT MAKES SAMMY RUN. Or Macbeth. Or Dracula. Or Elmer Gantry." Swain then adds that though readers are accustomed to focusing upon heroes who have "positive" aspects, "a focal character may prove the opposite, yet still intrigue us even as we loathe him."
Since my idea of narratological analysis rests heavily on the notion of the analyst being able to determine the nature of any narrative's *centricity"-- which on occasion becomes relatively complicated-- Jung's distinction may prove useful.
This 2009 essay contains one of my earliest's formulations of the "combative" and "subcombative" modes of conflict, but these modes do not in any way correlate with the prospective "ego/affect" formula. I revisit Rider Haggard's two classics, KING SOLOMON'S MINES and SHE because they contain many nearly identical plot-elements-- European explorers finding a lost land and dealing with the hostile rulers thereof-- and were written within roughly a year of one another. Even the viewpoint characters of the two novels, Allan Quatermain and L. Horace Holly, have similar physical descriptions and misanthropic outlooks.
Of the two terms I've extrapolated from Jung, KSM would be "ego-oriented." Though the novel goes into great detail describing the isolated country of Kikuanaland-- a land so remote that the black Africans can be tricked into thinking the white explorers to be star-gods-- the narrative focus is not upon the Kikuanas, or even on the return of the exiled king Ignosi, who successfully regains his throne. The emphasis is always upon Quatermain's fortunes and activities, with a lesser emphasis upon the other explorers.
In contrast, SHE is an "affect-oriented" novel. Although the reader may well worry about the fate of narrator L. Horace Holly, the imaginative center of the novel is the titular SHE. (I should mention that a work's title should be any kind of indicator of centricity, especially given the counter-example of KING SOLOMON'S MINES.) Once Haggard has sketched the backstory of Holly and his relationship to his surrogate son Leo Vincey, they develop no further, and once they reach the lost city of Kor, they become no more than satellites to the complicated mystery of She-Who-Must-Be-Obeyed. I should note that in KSM Haggard tosses off the idea that the villainess Gagool may be a deathless immortal as well, or that she may just be a descendant of a heritage passed down through generations, like Lee Falk's Phantom. But Gagool is meant to be a flat character, less explored than Kikuanaland or King Ignosi. In SHE the character of Ayesha is the "affect," the "reality," about which all of the main characters orbit.
Of course it should be taken for granted that despite Jung's privileged use of the term "reality," he is manifestly not claiming that the "extravert" orientation is more "realistic" than that of the "introvert." He's merely showing two forms of validation, without claiming the superiority of one to the other, which once again demonstrates his pluralistic philosophical nature.