Historians of modern design and sociology have shown little interest in the leaders of the ever resourceful and influential British Positivist Society. One of the aims of this essay is to show that the Positivist polymath Frederic Harrison (1831–1923) cultivated ideas and practices that are compatible with modernists’ aspirations to improve the lives of the masses. It is accordingly shown that Harrison was an ardent supporter of working-class causes and that on this basis he developed sociological survey methods and produced (...) social programmes to initiate the comprehensive reorganisation of cities. Harrison intended to realise a modern utopia called the “Occidental Republic”, created by Auguste Comte, the Positivist Philosopher who – during the 1830 and 1840s – introduced both sociology and the Religion of Humanity. While many studies pore over the Positivists’ “church” rituals, this essay is the first to argue that the Religion of Humanity and sociology were of equal consequence – and that together they formed the basis of their controversial spatial theory and practice, which was considered the means to realise Comte’s utopia. This vision, it is argued, is central to appreciating how Positivism percolated into the “modern movements” of architecture and planning. (shrink)