Communism and Capitalism
Capitalism depends on certain aspects of the conditions in which we live – on the structure of time and the conservation of matter. The basis of capitalism is that if a tiger rushes towards you, you need a gun. If you acquired a gun at some point in time previous to the tiger's attack, and have it ready to hand, this is useful. If you have not actually got a gun, but know that you could acquire one at some point in the future, this is not so good. The problem is to survive so as to reach that future.
The essence of communism is that nobody may have guns unless everybody has guns, and the only way anybody can get guns is if the Collective-at-Large sees fit to make a universal issue. And you may not have a better gun than the Collective sees fit to issue for everybody. So if the Collective does not actually get round to issuing any guns at all, everybody will be equally liable to be eaten by tigers.