ABSTRACT
Ideas are central to understanding how physical geographers have observed and analysed the physical world. Ideas are not static, they change over time as well as from place to place. Ideas influence what we believe and how we understand reality. Ideas change internally, through the practice of a discipline, as well as externally through the social contexts within which physical geographers work. Differing ideologies, different philosophical approaches can influence the questions asked as well as the answers sought. Exploring this complex tangle of influences has often involved detailing the history of a subject. By following the ‘great men’ (and it usually was men in nineteenth-century academia) and their works, the key concepts from different periods can be traced and some sort of model of change developed. Often as important is the use of such a history to justify the current set of concepts within a subject.
