This text is an essay on the relationship between ways of thinking, the rich seams of contemporary thought and the forms of the house, of planning and living in it. The descriptive method is based on seven guided visits to a group of real or imaginary houses that make up a sufficiently extended panorama for understanding what the 20th century has bequeathed to us in the way of a heritage. In order to choose the houses to visit it was necessary to narrow things down, simplify them, by highlighting a series of archetypes defined by their most pronounced features. The reader, then, won't find any of the masterworks built by modern architects -neither the Villa Savoye, nor Fallingwater, nor the Villa Tugendhat-but mostly imaginary houses, houses constructed by manipulating different references. In short, this book invites the reader on a fantasy tour, one whose aim is not just to celebrate the diversity of the 20th-century house but also to stimulate the pleasure of thinking, planning and living intensely, to promote the appearance of a house that does not yet exist.