###Human: When will a patient with paranoid schizophrenia have delusion? ###Assistant: Hi. Delusions are fixed firm unshakable beliefs that are not in keeping with a person's cultural, social and educational background. If a person is deluded about something he has it 24x7. But that does not mean that all of his functionality will be gone. Except for the domain of the delusion, he may function well. For example, if a person is deluded about being followed and spied upon, he may still be good at his work. Speaking of criminal responsibility. Well, it is a tough thing to prove or disprove but theoretically, if a person is deluded about his wife but hunts down a deer because he wants its skin or horns, he will be responsible for his crime because, at that time, he was not having a delusion about that deer.