The key to unbounded growth is commoditization of living necessities. What is necessary to live is produced more efficiently as time passes, so they take smalle

The key to unbounded growth is commoditization of living necessities. What is necessary to live is produced more efficiently as time passes, so they take smaller share of the overall economy, while luxuries grow to take bigger share. Luxuries are less resource intensive so they can grow their share without straining the earth, simply by increasing price.