Call me a coward, but I tend to think that love is one of those experiences that are so intimately bound up with the essence of being human that they can only be lived, and any attempt to "explain" or "define" them is doomed to failure. The nature of the soul, the notion of beauty, and the experience of death fall into the same category.
I am thus tempted to fall back upon my old standby in situations of this sort: "What we cannot speak about we must pass over in silence." Ludwig Wittgenstein, Proposition 7, Tractatus Logico-Philosophicus (translated by David Pears and Brian McGuinness) (1921). Of course, Wittgenstein is only repeating what Taoist and Buddhist philosophers stated centuries ago. And what they say is true, you know. (Contrary to what purveyors of Science would have you believe, all of this explaining we moderns engage in gets us nowhere.)
Claughton Pellew-Harvey, "View from the Studio" (1930)
Still, I believe that the subject of love can be approached aslant, which is where poetry comes in. Hence, for example, I recently came across the following poems by Robert Herrick.
Love, What It Is
Love is a circle that doth restless move
In the same sweet eternity of love.
Robert Herrick, Poem 29, Hesperides (1648).
Herrick's most recent editors suggest that the source of the poem is a traditional proverb. Tom Cain and Ruth Connolly (editors), The Complete Poetry of Robert Herrick, Volume II (Oxford University Press 2013), page 519. They also cite two lines from a masque by Ben Jonson titled "Love's Welcome at Bolsover" as a possible source: "Love is a circle, both the first and last/Of all our actions." Ibid. Finally, they reference a passage from Robert Burton's Anatomy of Melancholy: "[Love is] circulus a bono in bonum, a round circle still from good to good; for love is the beginner and end of all our actions." Ibid.
I next encountered this, in which "from good to good" (coincidentally or not) makes an appearance:
Love is a Circle, and an Endless Sphere;
From good to good, revolving here, and there.
Robert Herrick, Poem 839, Hesperides.
This helps to illuminate "Love, What It Is." To some extent. Both poems sound lovely, and feel as though they have the ring of truth. After encountering them, I came across a third poem by Herrick which brings things together.
How Love came in, I do not know,
Whether by th'eye, or ear, or no:
Or whether with the soul it came
(At first) infused with the same:
Whether in part 'tis here or there,
Or, like the soul, whole every where:
This troubles me: but I as well
As any other, this can tell;
That when from hence she does depart,
The out-let then is from the heart.
Robert Herrick, Poem 73, Hesperides.
"This troubles me" is marvelous. And this is wonderful: "Or whether with the soul it came/(At first) infused with the same." As is this: "like the soul, whole every where." In this context, love as a circle, love as "an Endless Sphere," and love as a "sweet eternity" make perfect sense. The final two lines are lovely, and bring us back to earth.
W. G. Poole, "Plant Against a Winter Landscape" (1938)
However, I do not wish to be reductive. (And I do not think that Herrick is being reductive. He simply provides us with beautiful possibilities.) Defining love destroys it. As I say, it is best approached tangentially, at an oblique angle.
Love Without Hope
Love without hope, as when the young bird-catcher
Swept off his tall hat to the Squire's own daughter,
So let the imprisoned larks escape and fly
Singing about her head, as she rode by.
Robert Graves, Poems (1927).
Few poems capture love's heart-pang and its internal airiness (that catch of the breath) as well as this.
Duncan Grant, "Girl at the Piano" (1940)
"Absence makes the heart grow fonder." Yes and no, experience teaches us. But I do think that the feeling of an absence -- of a lack -- is another way of approaching love aslant. Absence brings home what fullness is. Or something like that.
Only the moon
high in the sky
as an empty reminder --
but if, looking at it, we just remember,
our two hearts may meet.
Saigyo (translated by Burton Watson), in Burton Watson, Saigyo: Poems of a Mountain Home (Columbia University Press 1991). The poem is an untitled waka (five lines, with a syllable count in Japanese of 5-7-5-7-7). It is prefaced by this note: "When I was in retirement in a distant place, I sent this to someone in the capital around the time when there was a moon." Ibid, page 123.
The Land with Wind in the Leaves
Distance cannot remove me from that place.
I stand half a world away and here it is:
A green sway and roar -- blue, vast, open
And refusing always to let me depart.
Yorkshire 1987 -- Tokyo 1992
sip (Tokyo/Seattle 1992).
Richard Eurich (1903-1992), "The Window"