Martin W. Lewis is a Senior Lecturer in International History in the Department of History at Stanford University. He is the co-author of The Myth of Continents: A Critique of Metageography (University of California Press, 1997) and the former associate editor of Geographical Review. In December 2009 he started, a blog which offers "brief, map-illustrated analyses of current events, both major and minor, from all reaches of the world."

You describe yourself as a "historical geographer." What does a historical geographer do, exactly? Could you give a thumbnail sketch of the development of historical geography as a research field? And how has new technology such as GPS and Google Earth changed your field?

By the standard definition, historical geography seeks to uncover the spatial patterns of earlier societies and to analyze the evolution of landscapes. The classic work in areal reconstruction is H.C. Darby’s six-volume Domesday Geography of England, which gives a snapshot of the English countryside in 1086 CE, based on the famous survey completed twenty years after the Norman conquest.

I was trained in the Berkeley school of historical geography founded by Carl Sauer, who emphasized the environmental consequences of the subsistence activities of rural peoples. But I now view the field much more broadly, regarding all works of historical inquiry that use maps to advance arguments as instances of historical geography. In this sense, more historical geography is currently being conducted in history departments than in geography departments. That said, the small number of geographers who conduct historical research produce some high quality work (see especially the Journal of Historical Geography).

Most historical geographers use basic documentary methods, focused on the close reading of primary sources. A few also employ scientific techniques, charting ecological change, for example, through tree-ring data or sediment cores. Another method is repeat photography; comparing archival and current photos can reveal all kinds of landscape transformations. Historical geographers use more maps than other historians, and they are generally keen to personally explore the places that they write about.

My own historical-geographical research has relied on a variety of methods. My current work entails examining old maps and geography texts to see how cartographers and other scholars divided the world in past times. My earlier work on environmental change in Northern Luzon in the Philippines was more multi-disciplinary. To determine the environmental baseline conditions of the late 1800s and early 1900s, I turned to papers of nineteenth century German ethnographers and Spanish officials, governmental reports of the American colonial administration, and unpublished diaries and photographs of early twentieth century American scholars, teachers, and administrators. To examine the transition from subsistence cultivation to intensive market gardening in the mid-twentieth century, I relied most extensively on living memory; I traveled widely to search out and interview elders, and then used standard techniques of oral history to assess the reliability of their accounts. Newspaper accounts and agricultural and forestry reports also proved useful.

The main technological innovation in geography over the past few decades has been GIS, or Geographical Information Systems, which weds mapping to digital databases to allow the ready construction of complex map overlays. A number of historical geographers and geographically inclined historians have made excellent use of GIS; see any of the works of Anne Kelly Knowles, especially Past Time, Past Place: GIS for History. I would also recommend the work of my colleagues in the Stanford Spatial History Project.

From The Boston Globe's The Big Picture, a photo essay of the miners rescued in Chile.

From Harper's, Gary Grenberg on the war on unhappiness: Goodbye Freud, hello positive thinking. Harvard's Shawn Achor on how to be happier. The Spoils of Happiness: Whatever happiness may be, it's not a state of mind. A review of What Is This Thing Called Happiness? by Fred Feldman. More Money, Less Mirth: Economist Carol Graham tries to fathom the sometimes paradoxical relationship between prosperity and happiness. Here are 5 things you think will make you happy (but won't). A history of happiness: We've forgotten much of what older traditions knew about happiness. Medical journalist Ian Smith uses past experience to inform his book Happy: Simple Steps to Get the Most Out of Life.

An interview with Steven Rattner, author of Overhaul: An Insider's Account of the Obama Administration's Emergency Rescue of the Auto Industry (and part 2 — and a response by Jonathan Bernstein). And here's Rattner on TARP, an unloved bail-out that saved America.

Andreas Follesdal (Oslo): Religious Liberty Versus Gender Equality: In Memory of Susan Moller Okin. Denise Walsh (Virginia): Culture Versus Women’s Rights Conflicts and Multicultural Policies. Charles Taylor on solidarity in a pluralist age. On multiculturalism, the cardinal rule is that all immigrants to Canada love their adoptive country but cling to the habits of home, but some immigrants chose Canada to get the hell away from their homescape and after arrival never gave the old country a second thought. How multiculturalism fails immigrants: Grouping people according to their "historical" cultural identity is both divisive and dangerous — migration is about change, not ossification. Slavoj Zizek on how liberal multiculturalism masks an old barbarism with a human face: Across Europe, the politics of the far right is infecting all with the need for a "reasonable" anti-immigration policy. From Alternative Right, Fjordman on Thilo Sarrazin vs. the multiculti oligarchs (and a response by Paul Gottfried). A review of Multiculturalism: Some Inconvenient Truths by Rumy Hasan. In the hands of today’s students, multiculturalism is a fruit that has over-ripened — the fact that all human beings are born equal has thoughtlessly become confused with the myth that all cultures are born equal.

The New York Times has a review of newly translated works by Roberto Bolaņo. The man without a country: Robert M. Downey on the cottage industry of Roberto Bolaņo (and more and more and more and more and more at Bookforum). From Swans, Peter Byrne on Roberto Bolaņo's Poetic Justice.