AS WE RODE a crowded midnight ferry across the Bosphorus strait, forty-eight hours into our frenetic marathon of biennial viewing, one of my most patient and scholarly colleagues cried out in exasperation, “Is there anyone who can tell me what ‘Saltwater: A Theory of Thought Forms’ means?!” This koan, equal parts Toni Morrison and MIT Press, is the title of the Fourteenth Istanbul Biennial, presented by the Istanbul Foundation for Culture and Arts and curated by Carolyn Christov-Bakargiev.

Part of the answer is a simple matter of historical definition. “Thought-forms” is a concept associated with