The field of political economy assumed its initial shape over the course of the eighteenth century in Britain, especially in the work of Adam Smith, and had become a powerful influence on a wide range of writers even before the revisions and reconceptions of the field by William Godwin, Thomas Robert Malthus, David Ricardo and Thomas De Quincey. Concepts basic to the developing discipline, such as the labour theory of value, the necessity of letting markets grow and change organically, and the importance of population size as an indicator of a nation’s well-being, were widely accepted at the close of the century, even by those who later turned into the ‘Lake Poets’. In 1800, for example, Coleridge defended Adam Smith’s opinion that grain markets will eventually ‘find their own level’ (like rivers) and so should not be artificially manipulated (like pumps). As this example indicates, eighteenth-century British political economy, which was a product of the Scottish Enlightenment, and nascent Romanticism emphasized the natural processes that bring humans and their environments into reciprocal relations. Both thought the life of the nation was constituted by the accumulated daily experiences and choices of common people, rather than the decisions of the powerful; both looked beyond the rational faculties (favoured by French philosophes) to emotions and sensations for the deepest springs of human motivation; and both tended to rely on free individuals and their instincts, rather than changes imposed by the state, to bring about social progress.