Modern art is discussed, admired, renowned, and sometimes reviled for many different reasons, but there’s one defining quality that usually stands out as a point of fascination or contention: It doesn’t look like anything “real.”

Constantin Brancusi And it’s true—a lot of modern art from the 20th century doesn’t bear a wholly physical resemblance to its subjects. But according to sculptor, the concept of “being real” is about a lot more than looking like nature. This idea was central to his work and is what made him so controversial in his time, and so pivotal to the evolution of sculpture.

Brancusi was born in 1876 in rural Romania. His father was a peasant, and Brancusi grew up distinctly outside of the traditional Western European narrative in which many of his peers were entrenched. Throughout his entire life, he embraced an outsider’s position—from the sandals he wore to the way he styled his hair and the folk music he listened to. Similarly, his artwork didn’t follow the style of his Western predecessors. It broke with the academic tradition, and helped shape the principles of radically reductive and non-representational modernism that are both celebrated and scorned today.