Sophie Rhyder’s sculpture “Rising,” in Salisbury, England. (Matt Cardy/Getty Images)
Eve Fairbanks, a writer who lives in Johannesburg, is at work on a book about South Africa.

When I was 12, I read a poem by Robert Frost called “To Earthward.” “When I was young … The petal of the rose it was that stung,” he wrote. “Now no joy but lacks salt, that is not dashed with pain and weariness and fault.” Reading it felt like peeping through a keyhole into the dimmer, holier room that would be adult life, a room whose wood was distressed, whose shadows were deep and whose silvers were tarnished, yet glowed; a magical place where salt became sweetness and pain could turn, through alchemy, into love.

Coming into my 20s, I came across it again. Instead of mysterious, it seemed to me bright and beautiful, so sweet I could almost taste it: Its description of youthful happiness, “the swirl and ache from sprays of honeysuckle,” was perfect to that time. And then, 10 years later, again. The poem’s cadences seemed jerkier than I’d remembered them, grittier, defiant.

This is art: a supposedly dead thing, letters on a page or pigment on a canvas, that, miraculously, seems to change its shape as we do. A painting of Johannesburg, South Africa, that looked dusky when we are sad brightens when we are happy. Its aggressive lines turn spiky, peppy. What book of social science, what piece by Malcolm Gladwell, adopts a different meaning when we read it at different times in our lives? The poetry critic Cleanth Brooks once wrote that a poem has an effect that is “massive,” contrary to its limited lines. It carries a shifting world of meaning that responds, like a friend, to the particular queries its human readers make of it.

When I hear a policymaker wants to cut the arts from primary education, I think of this friend-like quality. Books and pictures and pieces of music are the best friends some children have. Art isn’t a teacher but a conversationalist, and thus — in drawing us out and seeking to know us — teaches us more than many textbooks and teachers can.