4 ms·

Easy, you put the transaction in the previous block. So the miner can only mine a block if they have already made the expenditure.

• seoaeu 5y ago
  What stops me from doing a hard fork to roll back both blocks?
  • lottin 5y ago
    If you spend more tokens than the tokens that were spent mining the last two blocks you can erase the transactions in those blocks, but isn't that also the case with PoW?
    • seoaeu 5y ago
      You aren’t following. The hard fork lets me double spend the tokens from those blocks.
      • lottin 5y ago
        Indeed, I'm not following your argument.
        • ogogmad 5y ago
          Stop asking people to do your homework.
• deleted 5y ago
  [deleted]
• ogogmad 5y ago
  What if I create a whole new chain? Will the transactions at the very beginning of that chain have to be added to the big, old chain? How far back do the common ancestors of two chains have to be for your auto-merging to happen? What happens if two histories conflict? Then in Version Control parlance, we have a "merge conflict".