Do we have too much stuff? That's the central theme of a new book by a leading anthropologist who goes back in time to ask whether our discovery of tools was in fact the beginning of the end of the human race. Since then, our desire to grow and build has led to the environmental consequences of today, as we drown in rubbish and the problems of climate change take effect. Chip Colwell's book is entitled "So Much Stuff: How Humans Discovered Tools, Invented Meaning, and Made More of Everything". He spoke to us in Perspective.