In 1913 Marcel Duchamp topped a kitchen stool with a bicycle wheel, “fork down” through a hole he had drilled in the seat, and parked this wheel-on-a-stool in his Paris studio. “I didn’t have any special reason to do it,” he later recalled. Instead it served as a “distraction” for the artist. Watching the wheel spin “was like having a fireplace in the studio, the movement of the wheel reminded me of the movement of the flames.”

Two years later, during the summer of 1915, Duchamp boarded a ship for New York. He situated himself on the Upper West Side and, later that winter, wrote a fateful letter to his sister Suzanne. Dated January 15, 1916, it explained, in affectionate but purposeful tones, that the Bicycle Wheel and another work, Bottle Rack, dated 1914, were “readymades.” He provided little explanation—“you know enough English to understand the meaning of ‘ready-made’ that I give these objects”—but we can glean the barest outlines of how these works were made: first, selection of a mass-produced object (although “selection” and, relatedly, “taste,” were thorny concepts for Duchamp); then an exchange of money and goods (the word “bought” is used twice); and finally a signature, inscription, and declaration of the work as art. But specifics aside, what is essential is that the idea postdated the work. This letter is the first record we have in which Duchamp conceptualized the Readymade.

Once this concept circulated beyond the intimate audience of his sister and into the broader world, it proved nothing less than revolutionary for the course of modern art. By proposing that ideas, not technical bravura or aesthetic pleasure, could be an artwork’s raison d’etre, the Readymade upended foundational assumptions of Western art, laying down questions that continue today: What do we understand art to be, and how elastic are these parameters? What is the artist’s role if historically prized qualities such as skill and the singularity of the maker’s hand are moot? Duchamp inspired new pathways of thinking and making, and expanded the limits of imagination, taste, and systems for determining artistic value. Over the course of the 20th century, the freedom inherent in Duchamp’s idea of the Readymade opened up new worlds of art—Pop, Minimalism, Conceptualism—and his expansive influence is embedded, like DNA, in the work of artists from Robert Rauschenberg to Andy Warhol to Jeff Koons.

Today we celebrate the centennial of Duchamp’s letter of January 15, 1916. For this occasion we’ve installed several Readymades in the Museum’s fifth-floor galleries, including Bicycle Wheel. (Although the 1913 original was discarded, it was refabricated in 1951 and entered MoMA’s collection in 1967.) You can also see the full checklist of works online. As part of the celebration, at 5:00 p.m. today Ann Temkin, MoMA’s Marie-Josée and Henry Kravis Chief Curator of Painting and Sculpture, will make remarks from the galleries, and we’re streaming the event on Periscope. Follow MoMA on Twitter @museummodernart to get the link to the broadcast.

Duchamp’s letter:

15th January approximately. My dear Suzanne, A huge thank you for having taken care of everything for me. But why didn’t you take my studio and go and live there? I’ve only just thought of it. Though I think, perhaps, it wouldn’t do for you. In any case, the lease is up 15th July and if you were to renew it, make sure you ask the landlord to let it 3 months at a time, the usual way. He’s bound to agree. Perhaps Father wouldn’t mind getting a term’s rent back if there’s a possibility you’ll be leaving La Condamine by 15th April. But I don’t know anything about your plans and I’m only making a suggestion. Now, if you have been up to my place, you will have seen, in the studio, a bicycle wheel and a bottle rack. I bought this as a ready-made sculpture. And I have a plan concerning this so-called bottle rack. Listen to this: here, in N.Y., I have bought various objects in the same taste and I treat them as “readymades.” You know enough English to understand the meaning of “ready-made” that I give these objects. I sign them and I think of an inscription for them in English. I’ll give you a few examples. I have, for example, a large snow shovel on which I have inscribed at the bottom: In advance of the broken arm, French translation: En avance du bras casé. Don’t tear your hair out trying to understand this in the Romantic or Impressionistic or Cubist sense—it has nothing to do with all that. Another “readymade” is called: Emergency in favor of twice, possible French translation: Danger \ Crise \ en faveur de 2 fois. This long preamble just to say: take the bottle rack for yourself. I’m making it a “Readymade,” remotely. You are to inscribe it at the bottom and on the inside of the bottom circle, in small letters painted with a brush in oil, silver white color, with an inscription which I will give you herewith, and then sign it, in the same handwriting as follows: [after] Marcel Duchamp.

[Francis M. Naumann and Hector Obalk, eds.; Jill Taylor, trans. Affectionately | Marcel: The Selected Correspondence of Marcel Duchamp. Ghent, Belgium: Ludion Press, 2000, 43–44.]