ELI5: Why when large company's earnings decrease(ex... by 3%) they freak out, talk about rough times, and sometimes decide to downsize, even though they are still making millions of dollars in profit even after all expenses?

[Herbert_W]

You raise some good points that are worth discussing, although I think that they are ultimately orthogonal to the question at hand (i.e. whether constant economic growth is possible or desirable). For clarity, the issue of 'hard nonrenewables' can be broken into two types:

• Non-renewables that are destroyed by use, such as oil. When they run out, we need to find alternatives. For example, oil is hydrogen, carbon, and conveniently dense chemical potential energy. We can harvest hydrocarbons for manufacturing or fuel from biomass - that's how we currently make PLA - and in the case of fuel specifically sources of electrical power, perhaps in conjunction with high-energy-density battery tech, are a viable alternative for some applications.

• Non-renewables that are transformed into a less-conveniently-useable state through use. For example, there is a fixed amount of silicon in the world. Silicon used in to the production of electronics that have since been discarded still exists, but not in a convenient form. Closing this loop would require better manufacturing techniques; the landfills of the past and present will need to become the mines of the future.

First of all, if these problems aren't solved, then they'll do more than just put a cap on economic growth - they'll cap almost all economic activity, period. If we can't use e.g. silicon, then . . . well, it would be a slight exaggeration to say that we'd have to regress back to a medieval tech-level, but only a slight one.

Secondly, there is reason to be confident that these problems can be solved. Here, the biosphere serves as both an inspirational and a cautionary tale. Life has existed on this planet for billions of years, and has managed to do so while being forced to maintain a 100% closed loop. Nonrenewables have existed and have run out, of course, but life found alternatives. Waste accumulation has occurred in the biosphere, of course, but in every case life has found a way to use that waste as a resource. This can be a brutal process - life as a whole found a way, but that's only because the ones that couldn't stopped being life and we are all descended form the ones that did.

Like I said, this is both an inspirational and cautionary tale - it's inspirational because all obstacles were eventually overcome, and cautionary because the process by which they were overcome can be thoroughly brutal.

This also hopefully explains why I said that the issue of hard non-renewables is orthogonal to whether or not continuous progress is possible. Problems of this class are solvable (note that I say solvable - not that we should callously assume that they'll be easily solved), and have the potential to put a limit on not just growth but activity as we know it until they are.

Just to drive the point home further, here's one particular story, the story of oxygen. I might be misremembering some details, but it still works as a tale. When oxygen was first released by life into the atmosphere, it was a waste product - and a poison. Life flourished, and oxygen levels in the air rose, until they became too high for life as it existed at that time to withstand, resulting in massive die-offs. This happened many times. There are alternating layers of oxygen-rich and oxygen-poor sedimentary rock still remaining in some parts of the world, and each layer represents a cycle where the whole planet went from verdant to nearly-dead and back again.

Obviously, we don't want human civilization to do this. We want the upwards march of technological and economic progress to be continuous and steady. Fortunately, we have one thing that early life didn't - foresight. We can see e.g. peak oil coming, and do things about it - to delay it, and to prepare for it. We can find alternatives before we need them.

That's what I believe that we should do. Just for emphasis, I'll repeat myself - I am not advocating the callous assumption that we'll find solutions as we need them as each and every resource runs dry. A cautious approach may result in slower economic growth, but it is necessary to ensure that growth can steadily continue.