sustainable is not a metaphor

We are the first people in history to live so surrounded by images that attempt to incite our desires, our appetites, our sense of a lack within ourselves; a lack which will be assuaged, an ache which will go away, if we can lay our hands only on that last, perfect, necessary, piece of stuff.

A system in which we all continually want more is not sustainable at our current levels of projected growth. When I say not sustainable, by the way, I'm not using a metaphor – "sustainable" is one of those words which is being hollowed out by overuse. I mean that we will run out of the resources to live like this.

John Lanchester