For the first time in 250 years, energy and natural resources have become limiting factors for further growth. Extracting more of them is becoming increasingly difficult, making it hard to expand the economy further.
This is hard to grasp for all of us, as our brains work best when they extrapolate past experiences. If that fails, we are getting confused.
When trying to understand the reasons for our recent problems to maintain growth, we have to re-discover an old truth: more economic activity means more energy and resource use.
Photosynthetic plant growth has always been the driver of our prosperity, but since the beginning of the industrial revolution we are tapping into fossil solar power at breathtaking speed.
The drivers of most economic planning, labor, capital and their productivity, are at the core of the concept described by the Cobb-Douglas production function. Unfortunately, this "unlimited" view has hard limits in energy and resource availability that didn't matter during the 20th century.
Many advanced economies seem to have become much more energy- and resource-efficient during the past decades, emitting far less greenhouse gases per unit of economic output. Unfortunately, the largest part of those improvements exist only on paper, as globalization and the related de-industrialization have driven the "heavy lifting" elsewhere.