An extended essay argues that social forces, not mere changes of size or material, determine architectural form, contrasting architecture with dress to highlight their different origins and variety. It urges historians to register both deep and ephemeral movements, uses tide-and-wind metaphors to explain limits to prophecy, criticizes fashionable predictions such as those about skyscrapers, and recommends projecting existing social trends into architectural equivalents as the safest method for anticipating future developments.