Our Scientific American 50 award for Policy Leader of the Year to Al Gore for spreading awareness of climate change was the most controversial item of the December 2006 issue. Some correspondents were wholly dismissive of Gore's efforts; others felt he erred in oversimplifying a complicated subject. "The earth's atmosphere is very complex, yet Gore asserts that climate warming is due to one factor: the amount of carbon dioxide in the atmosphere," wrote H. G. Stuebing of Doylestown, Pa. "It seems only prudent to reduce CO2 emissions, but it is not clear that this will solve the problem."

Questions of scientific consensus regarding other topics in the issue inspired respondents to pontificate on the legitimacy of subliminal persuasion, the definition of an "industrial revolution," and the moral implications of emergent information-scanning technology.