The physicist Albert Bartlett has highlighted our mathematical shortcomings in his presentations, stating, “The greatest failing of the human race is our inability to understand the exponential function”
Rob Dietz and Dan O’Neill in Enough is Enough: Building a Sustainable Economy in a World of Finite Resources
A small, but constant, rate of growth causes a rapid rise in population. The same applies to national GDP.
The rule of thumb for doubling period is to divide 70 by the percentage. World population is growing at a little over 1% a year, so is on track to double to 14 billion in around 70 years, say by 2080. By the same token, world economic growth is over 2% a year, so our throughput of energy, minerals and food is set to double between now and, say, 2045.
That means: if we are burning up a lot of energy today, we’ll be burning up twice as much in 30-or-so years’ time (and four times as much 3o years after that). If we’re eating our way through a lot of fish and pork now, we’ll be eating our way through twice as much in 2045 (and then four times as much). If we’re drawing an agricultural bounty off the land we cultivate now, we’ll need to have doubled (and then quadrupled) the size of that bounty. If we’re gouging a lot of minerals from holes in the ground now, we’ll be gouging out twice as much (then four times as much). If we’re expelling a lot of effluent and emissions and non-degradable plastics into the soil, sea and air now, we’ll be expelling twice as much (then four times as much). That’s because GDP, in effect, measures throughput of resources, from land and sea back to land and sea, via human “consumption.”
Except, it’s not going to happen. Not unless a readily accessible photosynthesis-powered back-up planet magically becomes available, loaded with the extra land we need for farming, mining and landfill, ready with non-acidic protein-filled seas and scoured with winds of clean, fresh air.
Any five-year-old child knows you can’t take seven mini chocolate eggs out of a bag that only has two mini eggs left in it, but for some reason — probably that inability to grasp the exponential function — we stumble ignorantly onwards, down into the black hole of economic “growth”.