Man Ray and Francis Picabia first met in 1915, through Marcel Duchamp. Yet while both were giants of the Parisian avant-garde, their acquaintance was never more than casual. This intimate exhibition of nine paintings imagines a dialogue between the two “Dada brethren,” as Timothy Baum, who wrote the show’s catalogue essay, calls them. The paintings, which have not been on view for decades, demonstrate the men’s defiance of convention, and their development through different phases of modernism. —E.C.