Among the many mysteries of our age is why, when faced with clear and sustained evidence that their seemingly laudable goal is unachievable, proponents neither reflect nor modify their plan. They simply double-down. Failed methods are intensified, public spending and subsidies are raised, commitments are restated in ever-more grandiose terms, marketing campaigns become deafening – and doubters are vilified rather than debated in good faith. Following his recent comments on how to deal, in a practical way, with global carbon dioxide emissions, Gwyn Morgan experienced the full force of this latter phenomenon. Here, he responds to his critics.