This collection of interdisciplinary essays is the first to investigate how images in the history of the natural and physical sciences have been used to shape the history of economic thought. The contributors, historians of science and economics alike, document the extent to which scholars have drawn on physical and natural science to ground economic ideas and evaluate the role and importance of metaphors in the structure and content of economic thought. These range from Aristotle's discussion of the division of labour, to Marshall's evocation of population biology, to Hayek's dependence upon evolutionary concepts, and more recently to neoclassical economists' invocation of chaos theory. Resort to such images, contributors find, was more than mere rhetorical flourish. Rather, appeals to natural and physical metaphors serve to constitute the very subject matter of the discipline and what might be accepted as the 'economic'.