“So few grains of happiness measured against all the dark and still the scales balance,” Jane Hirshfield wrote in her stunning poem “The Weighing.” In how we chip from the monolithic weight of the world those osmian grains of happiness lies the promise of an answer to the abiding question: How, in this blink of existence bookended by nothingness, do we attain completeness of being?

That is what Anne Gilchrist (February 25, 1828–November 29, 1885) — a woman Walt Whitman cherished as “a sort of human miracle,” whose “vision went on and on” and who “belonged to the times yet to come” — returns to again and again, each time quarrying new strata of insight, in the forgotten treasure The Letters of Anne Gilchrist and Walt Whitman (free ebook | public library). Radiating from the pages of her beautiful and heartbreaking love letters to Whitman is an uncommonly original and penetrating mind in dialogue perhaps even more richly with itself than with its half-attentive correspondent. (Whitman responded to a fraction of the letters; he could not, for the obvious reason, meet her romantic ardor — but he relished and responded to her exceptional mind.)

By the time Gilchrist encountered Whitman’s soul-salving poetry, which she helped popularize in England with her coruscating review, she had been widowed for more than a decade, raising her four children as a single mother and making a living by her pen in an era when very few women were published authors — notably, her biography of William Blake, on which she had collaborated with her husband until his death, then finished by herself to establish the forgotten Blake, who had died an obscure outsider artist almost entirely unknown as a poet, as a creative icon for generations.

On the second day of summer in 1869, in consonance with her contemporary and compatriot Elizabeth Barrett Browning’s insistence on happiness as a moral obligation, Gilchrist writes in a letter to William Michael Rossetti — Christina Rossetti’s brother and Whitman’s British publisher, who had boldly brought Leaves of Grass to England when it was scorned in America and who would eventually introduce Gilchrist and Whitman:

I used to think it was great to disregard happiness, to press on to a high goal, careless, disdainful of it. But now I see that there is nothing so great as to be capable of happiness; to pluck it out of “each moment and whatever happens”; to find that one can ride as gay and buoyant on the angry, menacing, tumultuous waves of life as on those that glide and glitter under a clear sky; that it is not defeat and wretchedness which come out of the storm of adversity, but strength and calmness.

Our greatest obstacle to happiness, Gilchrist intimates, are our illusions of finitude and fragmentation — a failure of imagination that becomes a self-imposed prison of smallness, from which we are liberated only when we learn to see the interconnected wholeness of the universe:

One of the hardest things to make a child understand is, that down underneath your feet, if you go far enough, you come to blue sky and stars again; that there really is no “down” for the world, but only in every direction an “up.” And that this is an all-embracing truth, including within its scope every created thing, and, with deepest significance, every part, faculty, attribute, healthful impulse, mind, and body of a man (each and all facing towards and related to the Infinite on every side), is what we grown children find it hardest to realize, too.

Fifteen years before William James devised his revolutionary theory of how our bodies affect our feelings and more than a century before our modern science shed light on how the mind and the body converge in the healing of trauma, Gilchrist makes a beautifully articulated, elegantly reasoned case for nondualistic wellbeing:

I feel deeply persuaded that a perfectly fearless, candid, ennobling treatment of the life of the body (so inextricably intertwined with, so potent in its influence on the life of the soul) will prove of inestimable value to all earnest and aspiring natures, impatient of the folly of the long-prevalent belief that it is because of the greatness of the spirit that it has learned to despise the body, and to ignore its influences; knowing well that it is, on the contrary, just because the spirit is not great enough, not healthy and vigorous enough, to transfuse itself into the life of the body, elevating that and making it holy by its own triumphant intensity; knowing, too, how the body avenges this by dragging the soul down to the level assigned itself. Whereas the spirit must lovingly embrace the body, as the roots of a tree embrace the ground, drawing thence rich nourishment, warmth, impulse. Or, rather, the body is itself the root of the soul — that whereby it grows and feeds. The great tide of healthful life that carries all before it must surge through the whole man, not beat to and fro in one corner of his brain.

Like Whitman, who both reverenced science and probed its limitations, Gilchrist bolstered her erudition and her philosophical ideas with an intense interest in astronomy, chemistry, and biology, keeping up with the latest discoveries of the time. Drawing on her respect for science, and echoing computing pioneer Alan Turing’s brokenhearted belief that “the body provides something for the spirit to look after and use,” she adds:

Science knows that matter is not, as we fancied, certain stolid atoms which the forces of nature vibrate through and push and pull about; but that the forces and the atoms are one mysterious, imperishable identity, neither conceivable without the other. She knows, as well as the poet, that destructibility is not one of nature’s words; that it is only the relationship of things — tangibility, visibility — that are transitory. She knows that body and soul are one, and proclaims it undauntedly, regardless, and rightly regardless, of inferences.

Complement with Gilchrist’s contemporary Mary Shelley on nature and the meaning of happiness and Whitman himself on what makes life worth living, then leap across epochs of scientific understanding to Harvard’s groundbreaking 75-year study of human happiness.