A group of scientists and science communicators has written an open letter to WAG, a TV production company, insisting that it make changes to its film The Great Global Warming Swindle before releasing it on DVD.

Perhaps the most shocking thing about the 38 scientists’ call for a film on global warming to be ‘corrected’ is just how anti-intellectual such a demand is. Ideas are developed, indeed facts are established, only through the most rigorous debate possible. As John Stuart Mill wrote nearly 150 years ago: ‘Complete liberty of contradicting and disproving our opinion is the very condition which justifies us in assuming its truth for purposes of action; and on no other terms can a being with human faculties have any rational assurance of being right.’ 

In short, the only way to test out ideas – to prove them or improve them, to see if they’re right or true or useful or nonsense – is by submitting them to free and open debate. Restricting the communication or publication of certain ideas damages intellectual debate across the board because it limits our ability to weigh things up and work things out.