Proof of work tells you which version of history has the most work behind it. Imagine you join the network, trusting nobody. All you trust are the laws of phy

Proof of work tells you which version of history has the most work behind it. Imagine you join the network, trusting nobody. All you trust are the laws of physics and computation. You ask everyone you see "What is the current status of the ledger?" People give you different answers. So you choose the answer that has the most proof of work behind it. This is the one that the world is most invested in.