In the article: "Better yet, if you happen to know a miner (we didn’t), you could have them include the transaction directly in a block" But how could you guar

In the article: "Better yet, if you happen to know a miner (we didn’t), you could have them include the transaction directly in a block" But how could you guarantee the miner was trustworthy, and wouldn't just take the money after you told them. Hmm...what if we could come up with some sort of smart contract... (recursion ensues)