Charles Jencks was a pioneer of postmodern architecture—or “bastard classicism,” as his American detractors put it. In 1979 the American-born polymath and his wife, the garden designer and historian Maggie Keswick Jencks, purchased a large townhouse in London’s Holland Park and extensively redesigned it over the next five years. At once a family home and a “built manifesto,” The Cosmic House nods to Ancient Egyptian, Baroque, and Hindu architecture, modern science and urban planning, the Zodiac, western philosophy, and much else besides. Jencks integrated his eclectic references into a rich (and kitsch) symbolic scheme that sought to reconcile micro- and macrocosms: domestic pleasures and cosmic immensities; private gags and philosophical traditions. A cantilevered spiral staircase at the center of the building, for example, doubles as a model of the solar year with fifty-two steps for each week; at its base is Eduardo Paolozzi’s circular mosaic Black Hole (1982). Leading off from this mosaic is the basement gallery, home to an elegant exhibition by New Delhi-based Raqs Media Collective. (Jencks was co-designing the gallery with his daughter Lily until his death in 2019; the museum opened to the public two years later.) Founded in 1992 by Jeebesh Bagchi, Monica Narula, and …