I Don’t Know if It’s Art, But I Know What I LikeWhat is art? For Italian artist Salvatore Garau, it’s… nothing. The 67-year-old sculptor recently sold his “immaterial” sculpture, “I Am,” for $18,300, Newsweek reported in June. The buyer got a certificate of ownership. Garau says his work is a “vacuum.”

“The vacuum is nothing more than a space full of energy, and even if we empty it and there is nothing left, according to the Heisenberg uncertainty principle, that ‘nothing’ has a weight,” Garau explained. The artist demands that the work be displayed in a private home free of any obstruction, in a 5-by-5-foot area, but he has no requirements for lighting or climate control.