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Money is often pictured as the root of all evil, but seldom are the times when people dedicate enough effort to understand what money is and represents.
If we can all agree that in a harmonious society we should all contribute to it somehow, the money we make or possess can be perceived, by large degree, as a measure of that contribution.
If we provide something to a lot of people or something that is scarce, we will be rewarded for that by a means of compensation that we call money. It could be goods, services or whatever, but most of the times we all agree that money is simply more convenient.
That is because money is an easy means of transaction, thus we can easily trade our contribution to society for other contributions, usually in the form of products and services. If you think about it, is not fundamentally different from the direct exchange of goods.
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To grasp this notion of money is to clarify the mind and get rid of a ridiculous sense of guilt when confronted with the unceasing desire of accumulating wealth.