I think I'll add my $0.05 too. :)
I've always equated capitalism with freedom: the freedom to create and keep the fruits of that creation. It seems that any non-capitalistic wealth distribution system must include force and coercion to redistribute wealth to those that did not create it.
The Marxist analysis is quite the opposite. (simplified and breifly:) A capitalist system is one whith two distinct classes, capitalists and workers. The tools and raw material is considered to be the "property" of the capitalist (which is enforced by the state), and since those are nessessary for creating things, no creation outside the capitalist control is possible. Instead the non-owning class, the workers, sell their labour. They get some compensation, the salary, but cannot keep the fruit of their work: the cars, cloths, programs, etc they produce becomes the property of the factory and by extension the capitalist, thus perpetuationg the system.
The capital (Machinery, Land, etc), is of course crucial to the creation of wealth. The capitalist, however, does not create that capital nor does he add any work to enrich it. He merly is fortunate enough to own it. Under the capitalist system, a large part of the wealth created by the working class is redistributed to the capitalists - and anyone who do not respect the latters property rigths will surely experience coercion! :)
It seems that most of the arguments against capitalism center around its treatment of the poor. What's wrong with typical "safety nets" of capitalistic societies such as welfare and (in the United States) Social Security?
Apart from the fact that many seem to consider them insufficient even to keep people out of poverty, this type of measures that try to graft equality on top of capitalism without changing the underlying system kind of miss the point.
To use an unorthodox example: the people who revolted against the Ancien r'egime did so not only because of the immediate economic conditions, but also because it was considered unjust that a small (nobel) minority should rule without doing any productive work, simply because of their birth. Giving the masses the bread they were demanding might have postponed the conflict, but ultimately what was needed was a redistribution of power, not food.
The point of the analogy should be obvious: the current system of a small minority that controls most organizations without doing any productive work, simply because of what they own, is unsatisfactory not only for the economic hardship that results, but also for more fundamental reasons.
I don't know of any economic system which is "more fair" than capitalism. Do any exist? Have they been tried and proven?.
Good question. One sometimes hear about "primitive" societies that were not capitalistic, as well as pre-industiralised Europe (often there are different classes in these societies too, but the ruling class use non-economic means, say religion, to maintain their power). Some of the east block countries in the cold war did manage to put an end to private capitalism, but they were often quite unpleasant to live in for other reasons. Marxism promises a utopian future, but it would be nice to have some less religious assurance. Of course, attempts to create some other system (the Spanish anarchists, the early Bolshevik revolution) had to fight quite desperately against the capitalist west. In any case, one can dislike capitalism even if no successful alternative has been presented.
If wealth is redistributed somewhat equally, what is the incentive for people to achieve or produce more than they are allowed to keep?. See say's writeup.
Do you think there could ever be a sustainable economic system based on capitalism in which caring for the needy was the responsibility of NGOs (non-governmental organizations) such as churches or charities?. Caring for the needy certainly is the resonsibility of everyone! Organizations and government can only act as our proxies. However, in a capitalistic society, the state is priviledged in being able to redistribute wealth from the capitalist class to the needy without the former's permission - the only non-governmental organization I can think of that succesfully pulled off that stunt was Robin Hood and his Merry Men. An economic system where the state stays low thus relies on the altruism or self-interest of the capitalist class. Surely, the conditions in the 19th-century industrialized countries show that to be undesireable?
How should freedom be ranked against economic equality? I don't belive freedom is possible without economic equality, nor equality without freedom.