the saying you can fool all people some of the time and some people all of the time seems optimistic

it's really more like you can fool most people all of the time

and the few people who can't be fooled usually do not believe anything at all regardless of whether it is true or false. i had a friend like this who simply assumed the opposite of everything he was told. 100% of the time. no exceptions.

so nobody actually analyzes information logically. people either blindly believe or automatically assume you're lying.

this means there is very little incentive to tell the truth. people either believe you or don't believe you based on what their personality is, not based on whether what you're saying lines up with facts, evidence or logic.