Thomas Homer-Dixon

At this web site you’ll find information about my background, teaching, research, and writing. The site includes some of my writings as well as a Forum where we can discuss issues of common interest. If you’d like to receive my newsletter, just enter your email address in the box at the bottom of the page. Enjoy your visit.



100 Scientists Call for an Oil Sands Moratorium


Consensus statement says the science is clear: there can be no more oils sands development if we are to solve the global climate crisis

June 10, 2015


More than 100 prominent scientists from across North America, including climate scientists, economists, geophysicists, and biologists, released a consensus statement entitled “Ten Reasons for a Moratorium” that shows why Canada and the United States should postpone new oil sands development.


Go to ­Consensus Statement or


(Photo by Peter Essick, National Geographic)



November 15, 2014  

Today”s Butterfly Effect Is Tomorrow’s Trouble
Toronto Globe and Mail

The monarchs are in trouble, but why should anyone but nature lovers care? There are two big reasons. First, what’s happening to monarchs seems to be happening to many other species around North America and the world. And second, what’s happening to monarchs reveals key things about the increasingly complex problems humanity faces.

Go to “­­Today’s Butterfly Effect Is Tomorrow’s Trouble.


June 23, 2014

Fixing the Connection between Science and Policy
with Heather Douglas and Lucie Edwards,
Toronto Globe and Mail

The connection between science and public policy within the federal government is broken, and the consequences for Canada are becoming disastrous. We propose four ways to fix this problem.

Go to “­­Fixing the connection between science and policy.





The Conceptual Structure of Social Disputes: Cognitive-Affective Maps as a Tool for Conflict Analysis and Resolution

with Manjana Milkoreit, Steven J. Mock, Tobias Scröeder, and Paul Thagard
SAGE Open, January-March 2014: 1-20.

We describe and illustrate a new method of graphically diagramming disputants’ points of view called cognitive-affective mapping. The products of this method—cognitive-affective maps (CAMs)—represent an individual’s concepts and beliefs about a particular subject, such as another individual or group or an issue in dispute. Each of these concepts and beliefs has its own emotional value. The result is a detailed image of a disputant’s complex belief system that can assist in-depth analysis of the ideational sources of the dispute and thereby aid its resolution. We illustrate the method with representations of the beliefs of typical individuals involved in four contemporary disputes of markedly different type: a clash over German housing policy, disagreements between Israelis over the meaning of the Western Wall, contention surrounding exploitation of Canada’s bitumen resources, and the deep dispute between people advocating action on climate change and those skeptical about the reality of the problem.

View the paper.



Growth, Environmental Damage, and Innovation

Talk at the Annual Conference of the Institute for New Economic Thinking, Toronto, April 12, 2014.

View the talk.


Catastrophe Response Surface


Catastrophic Dehumanization: the Psychological Dynamics of Severe Conflict

A presentation at the Oxford Martin School, University of Oxford, April 17, 2012.

Dehumanization is arguably a defining feature of the most brutal acts of human violence, such as saturation bombardment of civilian populations, terrorist attacks on urban centers, intense battlefield combat, and genocide. I propose a psychological explanation of this phenomenon that uses a catastrophe manifold to describe a set of psychological states in an individual’s mind and the possible pathways of movement between these states. The manifold exists in a three-dimensional phase space defined by the variables identity, justice, and structural constraint. It specifies five hypotheses about the causes and dynamics of dehumanization. Taken together, these hypotheses represent an overarching theory of the nonlinear collapse of identification at the level of the individual.

View the talk.