Some more thoughts on beauty:

One component of beauty is complexity—a feeling that there is more to something than you can fully understand or grasp. It is what makes us feel like this beautiful thing we’re encountering is something we could possibly return to or explore/ponder/consider further, even if we know we probably won't—and we do return far less than we ever intend to. Sometimes, I’ve found, when I do return to something, it is much less rewarding than I thought it would be. Its freshness is gone, or it ends up being less interesting, or less impactful. But the initial perception of deeper substance, whether real or imagined, seems to be at least a frequent component of the beauty experience.

Though seemingly paradoxical, simplicity (at least the beautiful variety) relies quite heavily on complexity—it is only when complexity can be distiled or organized that simplicity becomes beautiful rather than flat or boring. To put it another way, simplicity is beautiful when it has complex, wonderous, and/or multi-faceted implications or associations. Complex associations do not have to be inherent to the thing/idea/etc.—they can come through contrast or juxtaposition. Juxtaposition is still an association. And since most people's very lives are rather complex, something simple can, by contrast to life in general, appear very beautiful.

On the other hannd, if something appears (or sounds, or feels) too complex, it becomes intimidating, and is therefore rejected or passed-over. Beauty requires a fairly substantial amount of initial understanding. And, of course, the “point of entry” for all of these elements will vary widely from person to person. There’s no magic complexity level that will appeal to all.