Consent Should Be Obvious
The standard for consent should be a high level of obviousness. For example, this daredevil was gored nearly to death by bulls and has stated explicitly that he plans to partake in the experience again.
What can be more obvious than his consent here?
Contrast this to the begrudgingly way everyone remits their tax demands. Even when it’s made voluntary, most people prefer not to.
Ergo, taxation is theft.