There are sound arguments for postponing aggressive emission reduction, such as cost savings, characteristics of the carbon cycle, and international institution building. There are equally sound arguments against postponing ambitious emission abatement, such as the stimulation of technological progress, intergenerational equity, and the impacts of climate change. The current state of knowledge does not allow for an unambiguous preference of one option over the other. However, there is little reason for not reducing emissions, not developing new technologies, and not building international institutions.