A thought in your head. You can hear it, but no one else can. Unless you read minds, but then you’d have bigger problems, like figuring how how to remain sane in large crowds.
Everyone has it. Those who have it least don’t know that they have it. Those who have it most wish they had less of it, but not too little or none at all.
Age. Young children don’t even know their age and extremely old folks wish they could turn back the hands of time, but not so much that they’re too young or they no longer have an age at all.
You will hang me. If they hang him, then the statement was true and they could only hang him for telling a lie. If they shoot him, then it makes the statement a lie and they were only to shoot him for telling the truth. An alternate solution is to say, “You will not shoot me,” leading to the same quandary for the killers.