The reason why they cant propose a new system is because it is either free or controlled market. Controlled market as we know is much worse than free market. Look at China before the were demand driven.

true... I ahve some fren whose business died casue of free market.... why? cos his customer can buy goods from his supplier and his supplier are willing to give the price lower than your cost 

Its still a hybrid between free and total controlled, Robert.

Greed, for a lack of better word, is good. Greed works. Greed is right. Greed clarifies, cuts through and captures the essence of the evolutionary spirit. Greed, in all its form, greed for life, for money, for love, knowledge has marked the upward surge of mankind. -Gekko

Free market as a concept does not suck. It only sucks because we are not in a perfect market nirvana. Yet, it is still the best thing that we have. Until we could find a better way to allocate resources, free market is here to stay.

faceless, I don't consider China's current economic system as Communistic. The only communist element they have right now is that government controlled companies make up a large percentage of their economy, over 50 percent if I am not mistaken. Besides that, their private companies operate in a fairly free-wheeling environment. In fact, because of their nearly non-existent welfare system, I would say that they are in fact less communist (or socialist) than many Western countries, especially the European ones.

Maybe it was me that did not clarify the word finite enough. Assume there is one hundred people in a country that adopts communism ideology.

The leader group 25 pal to plant vegi, 25 pal to make clothes, 25 pal to make houses and 25 pals to make weapons. And he came out with their own currency for circulation. As you might imagine, the price you sell for the vegi and clothes are more or less fix. The money becomes a medium to trade different necessity. If 1 million dollars was printed, it would be more or less staying the same for a very long time.

The following questions raise:
1) How to calculate GDP for each people in the country?
2) How to calculate inflation which is a barometer for demand and supply?
3) The value of clothes and vegi are hardly demand and supply driven, how to determine the value of it?
4) How the leader know that 25 person planting vegetables is enough for national consumption, if it is not demand and supply driven?

Few months back, North Korea raised help to UN community asking for food supply as many of the citizens in the country live in starvation, however this request was turned down by UN. The reason provided was if North Korea afforts to make nuclear weapons, didn't see why they couldn't affort to feed their citizen. One can argues that it was UN that closed off the two way trading between North Korea and the rest of the worlds, the point here is North Korea which adopt purely communism ideology is not self sustainable.

In contrast, capitalism does not impose any restriction to the price of a product and services. A bag could be range from 10 dollars to 1M dollars as long as demand and supply calls for it. The GDP for a country is theoritically infinite, depends on how well the products that they produced are needed by the rest of the worlds.

When the price of the product reaching sky high, at one point it will burst just like all the bubbles burst happened in the history. One need to be smart enough to different between the intrinsic values of a products and services against the price pay. Like what Warrant Buffet has quoted: "Price is what you pay, value is what you get".

This is what make capitalism so seductive and dangerous at the same time.

Excluded the discussion of greed here. Be it capitalism or not, it is always an issue and need to be regulated.

Just like what illustrated in Al Gore's an inconvenient truth video, which won him a nobel prize in peace. Although whether he walks the talk is questionable.

There will always be endless discussion on how do we weight on what we have achieved, to the expend of consuming our very own mother nature.

Do we measure the value of a human by what he own or what he do?

Who do we value more? An environmentalist named John or Bill Gates? If we only have one choice to be friend with only one of them and he will be friend with us, who would that be?

Off topic a bit I would say 

it doesn't matter what kind of economy system the world has, as long as people act like assholes toward each other, any kind of economy is flawed.

if i were a supreme leader of the world, i'd put less focus on economy and tech advancement and more focus on teaching everyone how not to be dicks first.