Economy concept flaw

I'm starting to run though what an economy is. In my head I imagine the millions of vendibles that lead to an economy. Societies all working together, apart and to win. Each striving to be better, obtain an advantage, keep an advantage. The only way to win is to help someone else loose.

One person decides they want corn and someone else has corn for sale, the two come together and decide how the transaction will happen. The government takes a slice for services they have provided like roads, water, sewage, police and every other goddamn thing. If the corn is bad, the buyer is unhappy. If enough buyers become unhappy, people stop buying corn. If too many people grow corn, there is an over supply and prices drop. When prices drop, the government does not get as much in taxes. Thus, the government has a hand in the quality control over corn.

As old people die off, their assets get redistributed. As new people are born they come in to new assets. Everyone who can works to some extent. That is people are out for their own survival. This is a predictable thing. If given the opportunity to not work they will not work for what they need. Ask any one who lived in Soviet Russia. If there is no motivation to do a good job, everyone does the minimum.

Some people want power and some people want to relax and drink beer. Others want to play video games. Most designs of ways to separate people from their money, also known as an economy, will cover as many possibilities as can be done. Still no flying cars, but they are working on it. Basically, if enough people are willing to spend money one it, it will be made.

Is economy a zero sum game?

The planet has a GDP (Gross Domestic Product). Goodness knows how you would measure it. No matter what numbers show up, they are meaningless because the people on the earth either have enough to get along or they do not. There is not much point in keeping track of the planetary GDP until there is another planet to compete with.

There is the rub. All these numbers exist just to tell winners from loosers in order to place the next round of bets. Some may say to make better informed investments, but they are indeed bets.

Any entity that can survive on its own without dependence on the rest of the world is not contributing to the world economy or detracting from it. There are people who think this sort of thing should not be aloud. Everyone must be made to be part of the economy. How else do you control them? If they are not worried about the things in the news, why will they get upset enough to vote.

The quickest way to guarantee everyone is part of the economy is to tax everything. I heard somewhere that online card based roll playing games cannot allow online trades of cards amongst it's members because sales tax would have to be collected.

I thought this post had a point there for a minute.