In the same manner, when the body has been under the influence of violent grief, any sudden joy has been known to overpower the system, and even produce instant death. We have an instance in history, of a mother being plunged into the extreme of grief, on being informed that her son was slain in battle; but when news was brought her, that he was alive, and well, the effect upon her spirits was such, as to bring on instant death. This event ought to have been unfolded to her in the most gradual manner; she should have been told, for instance, that he was severely wounded; but that it was not certain he was dead; then that there was a report he was living, which should have been gradually confirmed, as she could bear it. The same observations may be made, with respect to hope and fear, or despair; the former is an exciting passion, the latter, a depressing one; but the one is only a lower degree of the other; for a moderate degree of hope produces a pleasant state of serenity of the mind, and contributes to the health of the body; but a diminution of it weakens; and a great degree of despair so accumulates the excitability of the system, as to render it liable to be overpowered by any sudden hope or joy afterwards applied. What proves that joy and hope act by stimulating, and grief and despair by withdrawing stimulant action from the body, is, that the former exhaust excitability, while the latter accumulate it. Joy, for instance, does not render the system more liable to be affected by hope, but the reverse; and the same may be said of hope. In the same way, heat does not render the body more liable to be affected by food, but the reverse. Both these are stimulants, and exhaust the excitability. But after heat has been applied, if it be followed by cold, a great degree of languor or weakness will take place; because we have here a direct debility, added to indirect debility. In the same way, grief succeeding joy, or despair succeeding hope, produce a greater degree of dejection, both of mind and body, than if they had not been preceded by these stimulant passions; because here, direct debility is added to indirect. The excitability is first exhausted, and then the stimulus is withdrawn.