Ecology is often said to be a domain of study where technocrats take care of carbon dioxide emissions, turn ever-growing piles of garbage into sources of renewable energy, and devise means of reducing the growing acidification of the oceans. New technologies are awaited to remedy all ills independently of how humans choose to domesticate the earth. Others, such as Félix Guattari, the philosopher and psychiatrist of the generation of 1968, contend that we first have to change our ways of thinking and, in an engaging formulation of his own signature, of being in the singular or in a group in order to address problems of nature. I will take another retrospective (and, hopefully, prospective) look at Guattari’s revolutionary essay, The Three Ecologies (2000; Les Trois Écologies, 1989) by bringing attention to singular and group subjects and, given the theme of this volume, to architecture both in a concrete and metaphorical sense.