I no longer agree with this previous tweet of mine - since 2017, I have become a much more willing connoisseur of mountains. It's worth explaining why. https://t.co/LerCobzgvo First, the original context. That tweet was in a debate with Ian Grigg, who argued that blockchains should track the order of transactions, but not the state (eg. user balances, smart contract code and storage): > The messages are logged, but the state (e.g., UTXO) is implied, which means it is constructed by the computer internally, and then (can be) thrown away. I was heavily against this philosophy, because it would imply that users have no way to get the state other than either (i) running a node that processed every transaction in all of history, or (ii) trusting someone else. In blockchains that commit to the state in the block header (like Ethereum), you can simply prove any value in the state with a Merkle branch. This is conditional on the honest majority assumption: if >= 50% of the consensus parti