Three recent developments—one scientific and two polemic—should enrich discussion about human activity and climate change. In popular media and much of government, however, no such discussion exists. That this is so provides more cause for fear than does whatever global warming may result from the use of fossil energy.The scientific development is publication of a paper in the American Geophysical Union’s Journal of Geophysical Research suggesting that nonhuman influences account for most observed warming over the past 50 years. Australian researchers J.D. McLean of Applied Science Consultants, C.R. de Freitas of the University of Aukland, and R.M. Carter of James Cook U...