ringo,
re: "...a person 'convinced' against his will isn't really convinced."
Does that mean that a woman who gets pregnant against her will isn't really pregnant?
According to the dictionary, to be convinced is to be free of doubt and to feel certain about the truth of an issue. If a person is said to be convinced, it doesn't matter how they came to hold the conviction . Either they are convinced or they are not. In the case of the jaywill quote, the first part says that they are convinced.