In one of our recent psy-phi dialogues, my friend Adrian Lory mentioned a book by Japanese-American psychologist Shige Oishi entitled Life in Three Dimensions. In addition to the dimensions of happiness and of meaning, Oishi adduces a third dimension of life experience: psychological richness. It's perhaps no coincidence that someone from Japan had this insight, because if you ask me richness is something like the psychological counterpart of umami in cooking: the savory taste produced by the proteins essential to life.
Naturally, there are countless ways to slice up human experience, but I'm rather attracted to the notion that psychological richness is like our taste for savory flavors. Following this analogy, we could see happiness or pleasure as similar to our taste for sweetness (indeed, the ancient Greek word for pleasure is derived from one of their words for sweetness). I'm not sure what the analogies are for the other three basic tastes - salty, sour, and bitter - but I'll leave that as an exercise for the reader, while noting that somewhere in his voluminous writings Nietzsche says you can't experience the greatest joy without also opening yourself up to the greatest sorrow.
Coming back to Shige Oishi, I'll observe that he provides some actionable advice about how to make your life more psychologically rich: for instance, to be more playful and spontaneous. I've been experimenting along those lines in my own life, with some measure of success. For instance, about a month ago I had to drive from Rockland, Maine to Boston and instead of driving straight through I visited the Portland Museum of Art, walked along the ocean from Pine Point in Scarborough to Old Orchard Beach, and then explored Newburyport, Massachusetts for a while. That made for a much more rich, interesting day. I think I'll continue to salt such spontaneity into my days going forward.
(Cross-posted at Beautiful Wisdom.)