A trustless system is, as you might suppose, any system in which no trust is required to perform what would normally be a trust-based function; no human participants are in the mix and no one is asked to believe or have faith in anyone else. The system is theft-proof, tamper-proof, and fool-proof, meaning there’s no counterparty risk, no one on the other side of a transaction who can screw you out of your money or your sovereignty, no one to not sign off or forget to flick a switch, so there’s a lot less room for things to go sideways. In theory, there’s not even a force majeure or Act of God clause in a truly trustless system, but in practice, only one system is truly trustless.