You can't grow forever. That doesn't make sense.
The more we grow the more science we create the more we have to learn. Sooner or later we'll be learning for most of our lives just to keep up with the new technology being invented. Then there will come a point where we can't grow any more. Technology has become so complicated that the human mind can't process it. Then growth will stop and we shall have to live in this perpetual state of a technological world where most of it is unintelligible to most people. And we shall have to subsist.
For those who think growth can continue forever are probably the same people who say "the oil will never run out" "the land will never run out just keep growing the population it makes us richer". Or maybe they think that we'll all transport our brains into robot bodies and keep growing.
Short sighted.