Really...is THIS the best that you can do in this debate. I hope not...

Sure there has, and it's called a mixed economy. Look it up sometime...I'll bet that you live in one right now and don't even know it. ;)

The USA has the most successful type of economy the world over, and that is a mixed economy, which is a mixture of capitalism & socialism. Now, some would argue that we need more of one & less of another, but the fact is that the USA does NOT have a purely capitalistic economy.

Very well said...greed is at the center of pure capitalism, and that kind of feeling does not always need to be a part of human nature.

Yes, the "free market" is a total human invention. It is NOT a law of nature at all.

"Sure socialism sounds good, but can it be implemented?"

You really need to look around. There are social democratic democracies all over the place!