In an essay on "Literature and Happiness" D. J. Moores defends works of literature which are basically happy in nature and their arguments seem relevant to assessments of popular romance fiction, with its guarantee of happy endings and preference for uplifting emotions:
Jonathan Haidt, an influential social psychologist, has demonstrated the complexity of elevation, [...] an emotion that Haidt “discovered” after reading Thomas Jefferson’s account of being uplifted by particular narratives in which a character behaves in admirably moral ways, cannot be dismissed as so much apolitical fluff that distracts us from real sociopolitical evils. It is equally complex, if not more so, as are the Aristotelian fear and pity that culminate in the tragic response. To my knowledge, no compelling arguments exist that prove negative emotions are any more complex than positive ones. The converse, in fact, may be true: recent research indicates that negative emotions might be neurologically and psychologically simpler, as they are implicated in instinctual survival mechanisms by prompting immediate action—fear makes us run, disgust makes us spit, anger makes us fight, etc.—whereas positive emotions exert beneficial downstream effects that prove too complicated to measure in the moments when they occur. Barbara Fredrickson, a pioneering research psychologist at University of North Carolina at Chapel Hill, has discovered that positive emotions are not epiphenomena or mere effects of some other cause but causal agents that serve a valuable purpose by undoing the effects of negative emotions: relieving stress; improving health; strengthening the immune system; providing a sense of meaning and purpose; and broadening and building psychological resources for the future.
According to Haidt, the emotion of elevation is characterized by all of Fredrickson’s downstream effects, and it also prompts us to behave in more altruistic ways, reorienting us away from self-focused concerns to altruistic ones, opening those who experience it to a whole family of other-directed emotions, such as gratitude, love, and empathy. At the least, then, inspiring narratives relying upon elevation for their aesthetic effects rival, in affective complexity, the fear, pity, and catharsis implied in the Aristotelian understanding of the tragic response. (263-64, emphasis added)
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Moores, D. J., "Literature and Happiness." Philosophy and Literature 42.1 (2018): 260-77.