Between 1926 and 1928, the philosopher Ludwig Wittgenstein designed a house for his sister in Vienna (the Kundmanngasse). This book aims to clarify the relation between that house and Wittgenstein's early philosophy. The starting point of its main argument is a remark from Diktat für Schlick (c. 1932-33) in which Wittgenstein proposes an analogy between ornaments and nonsensical sentences. The attempt to extract from it an account of the relation between the Kundmanngasse and the Tractatus Logico-Philosophicus (1921) leads to the writings of Adolf Loos (whose...