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How to Run a Blockchain on a Deserted Island with Pen and Paper

What are we trying to achieve? Its very simple actuallyall were trying to do is maintain a simple table of balances on a piece of paper. This table will show how many coins each of our heroes has. The trick is, because we cant have one piece of paper that holds the only source of truthwere going to have to keep things equal and let each of the gang maintain their own versionthis is the decentralized part. And naturally, were also going to hope that all 4 pieces of paper eventually show the same thingthis is the consensus part.