[sparkie]

In Bitcoin, you trust only your own node. You don't place any trust in particular third-parties - you only accept communication from a large number of randomized nodes in hope that at least one of them is honest, which is sufficient to reveal the dishonesty of all others. (ie, you have not been eclipse attacked).

You then need to have confidence that humans will always act in their own self-interest, and that you are not important enough that a sufficiently large portion of participants would act against their own interest in attempt to try and scam you.

Acting against your own interest means deliberately losing money by trying to coerce a large number of economic participants to act against their own self-interest in order to benefit you.