ABSTRACT
A person enjoys positive liberty when he is an agent who is in control of what his plans for action are, even if he acts under all sorts of external constraints and obstructions and thereby has his liberty restricted. It is at least logically possible for an agent's desires, beliefs, or even his state’s of character and personality, to be deliberately implanted in him through subliminal advertising, hypnosis, brainwashing, or by means of the electrical stimulation of a part of his brain. The person is caused to have, or caused to form, such intentions as another wishes him to have. Hence, regardless of how it may ‘feel’ to him from the inside, from the external point of view people can see that he is not in control, not self-determining. It seems that he is a puppet, another's plaything. The plans he fulfils or purposes he executes, even if he is unconstrained, are not properly his.
