At least as far back as the ancient Greeks, poets and philosophers have struggled to define the nature of beauty. More recently—that is, for the past 150 years—psychologists have joined the effort to discover why we find certain sounds and images aesthetically appealing.
Answers remain elusive, and a new analysis in the journal Current Biology helps explain why. It finds some preferences—including our inclination to favor curves over angles—appear to be universal.
However, New York University psychologists Aenne Brielmann and Denis Pelli report that individual differences "outweigh general tendencies in most aesthetic judgments. Even for faces, which are popularly supposed to be consistently judged, individual taste accounts for about half the variance in attractiveness ratings."
To a large extent, beauty really does seem to be in the eye—and brain—of the beholder.
Brielmann and Pelli offer a mini-primer on the field of "empirical aesthetics," and the many attempts to create a universal theory of what constitutes beauty. Few have survived close scrutiny.
"Perhaps the most broadly established aesthetic preference is the one of curvature over angularity," they write. "People like the appearance of otherwise equivalent shapes and objects more if those contours are round rather than sharp and angular, and this is the case in various cultures around the globe."
Another widely noted commonality is the preference for symmetry over asymmetry, which has been shown "in abstract shapes, faces, and patterns," they add. Evolutionary biology may explain at least why we prefer symmetrical faces; the researchers note they "may indicate health, and thus higher mate quality for producing children."
But like so many other qualities the researchers examined, symmetry is beautiful—except when it isn't. "The asymmetric beauty mark that is a trademark of the much-adored face of Marilyn Monroe is a blatant exception to the general rule that symmetry enhances beauty," Brielmann notes.
Along those lines, it's worth remembering that the term "baroque" originally meant "irregular pearl." It's the irregular melodies and disjunctive harmonies of Bach and Handel that make their work unique—and beautiful.
Returning to the visual realm, "An average preference for colors of blue-green cold hue, relatively high saturation, and lightness is quite reliably found in Western adult observers," the researchers report. "This preference is, however, culture-, gender-, and age-dependent."
Similarly, follow-up studies have "repeatedly failed to replicate" 19th-century studies reporting the inherent appeal of the "Golden Ratio" so frequently found in classical art.
How long it takes us to recognize beauty is also unclear. The researchers note that increasing the amount of time we're exposed to an image from 50 to 500 milliseconds increases aesthetic appeal, which suggests we register beauty in the blink of an eye. But they acknowledge the "many accounts of rare experiences of great beauty that arise only after many minutes of exposure."
According to Brielmann and Pelli, we do know one thing in this realm for certain: "There is an especially tight, linear relation between beauty and pleasure responses." This, they write, suggests beauty "is a pleasure that is special in exceeding all pleasures."
Perhaps it's time to re-examine that Grecian urn and revise Keats' conclusion. Beauty is pleasure, pleasure beauty. And that's the truth.