In the quad of Elements containing the Problem Element, there is also its counterpart, the Solution Element, which is indeed the solution to that particular problem. There are also two remaining Elements in the quad: The Symptom and the Response. If the Problem is a disease and the Solution the cure, then the Symptom is the primary symptom of the story's problem and the Response is that symptom's most appropriate treatment.

As suggested, Main Characters do not have to contain the Element that is the cause of the problem. But if they do not contain the Problem Element, they will contain one of the other Elements in this crucial quad.

For example, we might decide that we want the problem and solution to be in the quad containing Logic, Feeling, Control and Uncontrolled. Any one of these can be the problem. If we select Feeling as the problem, then Logic will be the solution. If we select Control as the problem, then Uncontrolled will be the solution. Once we decide one pair to be the Problem-Solution pair, the other pair is the Symptom-Response pair.

Symptom is simply descriptive of what the Main Character believes the problem to be; Response is what he feels the solution is. So, for every actual Problem and Solution, there is a matching Symptom and Response. Which Element is symptom and which is response is determined by other dynamics at work in the story.