"After basic needs are met, higher incomes produce gains in happiness only up to a point, beyond which further increases in consumption do not enhance a sense of well-being. The cumulative impact of surging per capita consumption, rapid population growth, human dominance of every ecological system, and the forcing of pervasive biological changes worldwide has created the very real possibility, according to twenty-two prominent biologists and ecologists in a 2012 study in Nature, that we may soon reach a dangerous "planetary scale 'tipping point.' " According to one of the coauthors, James H. Brown, "We've created this enormous bubble of population and economy. If you try to get the good data and do the arithmetic, it's just unsustainable. It's either got to be deflated gently, or it's going to burst." In the parable of the boy who cried wolf, warnings of danger that turned out to be false bred complacency to the point where a subsequent warning of a danger that was all too real was ignored. Past warnings that humanity was about to encounter harsh limits to its ability to grow much further were often perceived as false: from Thomas Malthus's warnings about population growth at the end of the eighteenth century to The Limits to Growth, published in 1972 by Donella Meadows, among others. We resist the notion that there might be limits to the rate of growth we are used to--in part because new technologies have so frequently enabled us to become far more efficient in producing more with less and to substitute a new resource for one in short supply. Some of the resources we depend upon the most, including topsoil (and some key elements, like phosphorus for fertilizers), however, have no substitutes and are being depleted."