How science works

Science is a process that advances our collective knowledge of the world by proposing and testing positive claims. Science is a social activity - not in the sense that a party is a social activity, something we do for the purpose of enjoying other people's company, but rather in the sense that a sports team or an orchestra is a social activity an activity that gains power from harnessing the skills and efforts of multiple people in pursuit of a common goal. The power of the social process of...

Normative statements

The arguments that people advance to support or oppose a proposed action rest on two kinds of support statements about what we know, or positive claims, and statements about what we value or should value, or normative claims. These two types of claim are fundamentally different. Examine the arguments advanced in any policy debate, and you will find a combination of positive and normative claims. Examine any highly contentious policy debate - like climate change - and you will find a confused...

Global climate change a new type of environmental problem

Of all the environmental issues that have emerged in the past few decades, global climate change is the most serious, and the most difficult to manage. It is the most serious because of the severity of harms that it might bring. Many aspects of human society and well being - where we live, how we build, how we move around, how we earn our livings, and what we do for recreation - still depend on a relatively benign range of climatic conditions, even though this dependence has been reduced and...