Because the terms moral and ethical both concern distinguishing between right and wrong or good and evil behavior, they are often used interchangeably. However, if we are to distinguish, according to the Merriam-Webster dictionary, to be ethical means to adhere to a system or set of moral values or principles. According to the same dictionary, to be moral means to behave in a way that conforms to ethical principles or to express or teach ethical values. For example, a story can be said to have moral. We wouldn't normally say a story has an ethic. The moral—or guidance towards right behavior or attitudes—expressed in a story would be rooted, however, in ethical principles about right and wrong. For example, the moral of the fable about the boy who cried wolf is that it is a mistake to tell a lie because then when you then tell the truth nobody will believe you. However, this moral is rooted in an overarching ethic that asserts that lying is bad—a social evil that sows confusion—and honesty a good, in that it promotes a secure, stable society in which words adhere to reality.