"The whole of nature was overturned"

Pullman is pulling together metaphysical notions of free will, theological debates surrounding God, questions of physics in the form of Dust (or matter) and here he draws in yet another debate, the ecological one. While climate change is a clear and present danger in our world, so too is it for Lyra's. Like the harmful CO2 gasses that we are not able to see, should we disassociate it with its religious connotations, Dust too has many similarities. Indeed, the threat takes on an even more deadly form in the world of CittĂ gazze, where they are the cause of Spectres that feed on the soul.

In fact, New Line Cinema teamed up with the World Wildlife Fund to produce an advert to educate . They concentrate on this exact problem with polar bears and their shrinking habitat. Here's the advert...