Object Lessons is a series of short, beautifully designed books about the hidden lives of ordinary things.Air conditioning aspires to be unnoticed. Yet, by manipulating the air around us, it quietly conditions the baseline conditions of our physical, mental, and emotional experience. From offices and libraries to contemporary art museums and shopping malls, climate control systems shore up the fantasy of a comfortable, self-contained body that does not have to reckon with temperature. At the same time that air conditioning makes temperature a non-issue in (some) people’s daily lives, thermoception—or the sensory perception of temperature—is being carefully studied and exploited as a tool of marketing, social control, and labor management. Yet air conditioning isn’t for everybody: its reliance on carbon fuels divides the world into habitable, climate-controlled bubbles and increasingly uninhabitable environments where AC is unavailable. Hsuan Hsu''s Air Conditioning explores questions about culture, ethics, ecology, and social justice raised by the history and uneven distribution of climate controlling technologies.Object Lessons is published in partnership with an essay series in The Atlantic.