Finally, Wirth cautions the reader by pointing out that the direction of the ongoing changes in urbanism will for good or ill transform not only the city but the world. Therefore, the concept of urbanism needs to be taken seriously. Only by means of some such theory will the sociologist escape the futile practice of voicing in the name of urban sociology a variety of often unsupportable judgments concerning such problems as poverty, housing, city-planning, sanitation and violence.