It would not alter her current web of belief in association with her son. For Joe, he knows that his mother is in an unstable mood. A good explanation to him is one that would not cause his mother any worry or anger. In this scenario, not only is the validity of an explanation susceptible to skepticism but more attention is paid to feelings. When one has a good background of the item being explained, a good explanation is more focused and specific.
Explanation needs to be self-evident.
For someone who is unfamiliar with the subject, they should be able to recognize the statement and reflect on it with sufficient care. Generalization may be acceptable depending on the person's knowledge. However, as the amount of knowledge increases, there is more difficulty in providing a valid explanation. Propositions need to be more verifiable. The need to be an adequate number of cases, the cases must be representative and consistent with other beliefs.