It seems odd, wrong even, that “patience” and “passion” — the twin roots of love — should share a root in pāti, Latin for “to suffer.” But anyone who has lived, who has loved unskillfully or loved the unskilled, knows that the experience can be our sharpest instrument of suffering. We say we “fall” in love precisely because we know we can get bruised, know that the trap door it opens beneath our feet hurls us into depths we are entirely unprepared to fathom.

The interesting question, the transformative question, is what happens after the fall.

“It is a subject in which neither intuition nor the behaviour of others will help the philosopher to the truth,” Robert Louis Stevenson (November 13, 1850–December 3, 1894) writes in his long, passionate, searching essay on falling in love. “There is probably nothing rightly thought or rightly written on this matter of love that is not a piece of the person’s experience.” He is writing out of his own experience: Twenty-seven and struggling to make a name for himself as a writer, he had fallen painfully in love with the radical Fanny Obsourne — ten years his senior, still married to the philandering husband she left, attending art school in Paris with her daughter. They would eventually marry and magnify each other’s lives beyond all imagination. (“Without Fanny’s influence,” Camille Peri writes in her excellent biography of the two, “Louis might now be a forgotten man of letters instead of one of the greatest voices in Scottish literature.”)

Love, Stevenson argues, is the only experience that truly astonishes us, jolt us awake from the slumber of preconception and expectation. And when it does, “it is not without something of the nature of dismay” that we look upon our new position — discomposed, disoriented, out of control. He writes:

Falling in love is the one illogical adventure, the one thing of which we are tempted to think as supernatural, in our trite and reasonable world.

That feeling, Stevenson reflects, infuses one’s sense of being with “a very supreme sense of pleasure in all parts of life — in lying down to sleep, in waking, in motion, in breathing, in continuing to be.” And yet at the center of something so concrete, so palpable, is a mystery:

It is a subject in which neither intuition nor the behaviour of others will help the philosopher to the truth. There is probably nothing rightly thought or rightly written on this matter of love that is not a piece of the person’s experience. The effect is out of all proportion with the cause. Two persons, neither of them, it may be, very amiable or very beautiful, meet, speak a little, and look a little into each other’s eyes. That has been done a dozen or so of times in the experience of either with no great result. But on this occasion all is different. They fall at once into that state in which another person becomes to us the very gist and centrepoint of God’s creation, and demolishes our laborious theories with a smile; in which our ideas are so bound up with the one master-thought that even the trivial cares of our own person become so many acts of devotion, and the love of life itself is translated into a wish to remain in the same world with so precious and desirable a fellow-creature.

What makes love astonishing is precisely the way it blindsides us, the way it cannot be willed or achieved or won on merit. He writes:

There are many matters in which you may waylay Destiny, and bid him stand and deliver. Hard work, high thinking, adventurous excitement, and a great deal more that forms a part of this or the other person’s spiritual bill of fare, are within the reach of almost any one who can dare a little and be patient. But it is by no means in the way of every one to fall in love… Many lovable people miss each other in the world, or meet under some unfavourable star. There is the nice and critical moment of declaration to be got over. From timidity or lack of opportunity a good half of possible love cases never get so far, and at least another quarter do there cease and determine.

And yet love is not a matter of persuasion. In a sense, the declaration of it becomes superfluous when the fact of it is self-evident and mutual. It is, Stevenson observes, something we must simply show up for, with passion and patience entwined. He outlines the discovery, the deepening, the development of love past “the simple accident of falling in love”:

Love should run out to meet love with open arms. Indeed, the ideal story is that of two people who go into love step for step, with a fluttered consciousness, like a pair of children venturing together into a dark room. From the first moment when they see each other, with a pang of curiosity, through stage after stage of growing pleasure and embarrassment, they can read the expression of their own trouble in each other’s eyes. There is here no declaration properly so called; the feeling is so plainly shared.

To remain in love, Stevenson argues in another essay, two people “must bring kindness and goodwill” to life beyond the fall. He considers the single most important element of lasting love, which is also the greatest kindness we can give each other and the most durable gesture of goodwill:

Veracity to sentiment, truth in a relation, truth to your own heart and your friends, never to feign or falsify emotion — that is the truth which makes love possible… With our chosen friends… and still more between lovers (for mutual understanding is love’s essence)… we must strive and do battle for the truth.

A century later, Adrienne Rich would sharpen this sentiment in her timeless definition of love as “a process, delicate, violent, often terrifying to both persons involved, a process of refining the truths they can tell each other.”

Couple with Stevenson on what makes life worth living, then revisit Roxane Gay on loving vs. being in love, Kahlil Gibran on how to weather the uncertainties of love, and Hannah Arendt on how to live with its central fear of loss.