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I've understood for a while that bitcoin mining was a process that required computers to solve increasingly difficult problems in order to mine a block.
It wasn't until now that I realized those "problems" are actually the act of keeping track of all bitcoin transactions, updating the block chain.
Before this, I thought every bitcoin client on earth did that work to keep trackof the block chain together.
With this new understanding, I have to ask:
When all bitcoins have been mined, and there is no more reward for this computation by butcoin miners to update/keep track of the block chain, why would people continue to spend the resources to accomplish that task?