- Food
- Clothing
- Shelter
Very soon, we would probably have to add the following.
- Air
- Water
For quite some time now, the atmospheric percentage of oxygen remains close to 21%. As far as I know, the only source of oxygen for humans (and animals) are plants (trees). Now, what if we wiped out every single forest in the planet? Inevitably, the oxygen percentage will come down and carbon di oxide percentage will go up (these two go hand-in-hand or nostril in-and-out).
(Abdul Kalam already imagined this scenario, per a forward I got) Soon (say twenty years from now), we may see oxygen bunks all around the place and these will not even be strange. Drive into the bunk, buy your oxygen supply for one week and you're all set. Then drive into another desalination bunk and buy your water supply for one week!
We'll get settled to the situation. Only, we'll be telling our children stories of how the world used to be when we had all these for free!