Torsten Hägerstrand (October 11, 1916, in Moheda – May 3, 2004, in Lund) was a Swedish geographer. He is known for his work on migration, cultural diffusion and time geography.
A native and resident of Sweden, Hägerstrand was a professor (later professor emeritus) of geography at Lund University, where he received his doctorate in 1953. His doctoral research was on cultural diffusion. His research has helped to make Sweden, and particularly Lund, a major center of innovative work in cultural geography. He also influenced the practice of spatial planning in Sweden through his students.
Early life
Hägerstrand's father was a teacher at a remote elementary school and the family lived at the school. Hägerstrand recalled that his early education was based on the pedagogical ideas of Swiss educator Johann Pestalozzi. Several of Hägerstrand's students speculated that his holistic and visionary thinking was rooted in his early education: He was taught local geography, history and folklore at home in the Pestalozzi tradition which was being introduced at that time. Cartography, geology, botany and agronomy were all interrelated parts of a more holistic understanding of processes within a spatial area. To start with, children learned about their immediate environment (e.g., the school room and the farm), then about the village, and gradually the whole district. As a pupil of Hägerstrand, it is easy for me to recognize parts of this tradition which later became what we today would refer to as an 'integrative perspective'.
Academic career
Hägerstrand entered Lund University in 1937. His 1953 doctoral thesis Innovation Diffusion as a Spatial Process gained fame for its innovative use of Monte Carlo simulation of demographic development. It showed how dynamic, incremental simulation of spatial processes could be used at the spatial scale of the individual as well as large spatial aggregates. Forty years later, geographer Andrew Cliff remarked on the foresight of Hägerstrand's methodology: "Bearing in mind that much of the research upon which the book is based dates from a time when computers were almost nonexistent, let alone used by geographers, it is remarkable that the simulation methodology which is so critically dependent upon computing power should have been contemplated."
Hägerstrand's research was aided by developments at Lund University, notably the establishment of the Siffermaskinen i Lund (SMIL), one of Sweden's first computers. Hägerstrand noted that the Swedish computer scientist Carl-Erik Fröberg, who had been Hägerstrand's "school-mate since secondary school", had introduced him to the Monte Carlo method that would define his doctoral thesis, following a trip by Fröberg and other young Swedish scientists to the United States, a trip that was financed by the Swedish government's project to build its own computer.
In 1969, he presented a paper titled "What about People in Regional Science?" to the European Congress of the Regional Science Association in Copenhagen, Denmark. This paper, published in 1970, developed two concepts: The need to study the individual in order to understand social and group practices. Modern cultural geographers commonly now study everyday practices on an individualistic basis, in order to understand larger scale patterns. The study of just groups creates a homogenization of reality and hides the truth. A link between space and time that had previously been poorly developed. Historically, social scientists had treated time as a relevant but external factor to spatial features. Hägerstrand's early work on innovation diffusion (studying the geographical spread of new technologies) made him realise that the two, though separate, were not independent of each other; they have what French theorist Henri Lefebvre would call a dialectical relationship.
Legacy
Hägerstrand's initial work was primarily quantitative, which is important as the discipline of geography was, when he published his first paper in 1942, a highly descriptive subject. In the 1950s he was a pioneer of geocoding statistical primary data. He developed models and statistical techniques, such as the time–space cube and time–space prism, which later became important in the development of geographic information systems that process and visualize movement data. His work informed the likes of Allan Pred and Nigel Thrift, who helped take it to the English speaking world.