The problem with: "From each according to his abilities and to each according to his needs"

There are two main problems with this the primary tenent of both Socialism and Communism.

The first is that people are greedy. Some people might give people a part of their earnings but they want some say in it when they donate to charitable organizations or directly to people in need.

So, when it is instituted in governments people find ways of getting out of these obligations by living in a black market economy, moving to another country, or some other means of making sure they get enough off the top before it goes somewhere else.

So, even though "From each according to his abilities and to each according to his needs" might be something Jesus would advocate, in reality it doesn't work because there are just too many corrupt and greedy people and when you base a government on this mostly what happens is a whole lot of people at the bottom are going to starve to death without clothes, a place to live or a place to work.

So, even though Capitalism is theoretically more cruel it tends to work better in reality than Socialism or Communism because at least when someone becomes rich most of the time they feel guilty if they don't mentor and help people not doing as well as they are. So, the rich tend to lift up others to a greater or lesser degree into higher economic status and time goes on.

However, now we are in a place in the world where because of overpopulation Capitalism might be doing the world more harm than good if we want the human race not to go extinct within 300 to 500 years.

So, thinking about this might be important for the next generations of young people in high school and college here on earth so they can better help the whole human race not go completely extinct from nukes or from wars or from plagues like Ebola or AIDS during the next few hundred years.