Earth is a lifeboat

Basically this is the problem and it's why no one wants to talk about it. Earth is a lifeboat and there are 7 people (7 billion people) who want to stay on lifeboat earth. The problem is only 1 (1 billion people are sustainable on earth for thousands of years at present. (in other words when oil runs out) humans likely will be forced back to 1 billion people or less eventually unless Solar and wind or some other form of energy is found to work for us. And even then if we have a better power source there isn't enough tillable land because of pollution at this point (unless people move underground, tear down all the cities and houses and use all the land above their houses and underground factories and malls for farming that is good for that. At that point maybe 13 to 14 billion people might live here in a steady state human replacement system where no one can be born unless someone else dies.

For example, if oil stopped suddenly 6 billion people would quickly or slowly die. This is the reality of the world today and we would be back to about 1900 once again except we would have some pretty cool technology that we might not be able to use anymore.(but some would still work).

So, basically imagine a real lifeboat and one person says: " Would all of you like to be eaten by sharks so I can live?"

There is a reasounding, "No!"

Of course. So, in the end everyone gets eaten by sharks when there is no more food or water (or they eat each other from drinking saltwater and hallucinating) from the saltwater.

So, earth is a lifeboat but no one likely is going to be the last one person left (at least at this point).