a story seeks to make an argument, a tale does not
A tale describes a problem and the attempt to solve it, ultimately leading to success or failure in the attempt. In contrast, a story makes the argument that out of all the approaches that might be tried, the Main Character's approach uniquely leads to success or failure. In a success scenario, the story acts as a message promoting the approach exclusively; in the failure scenario, the story acts as a message exclusively against that specific approach. Tales are useful in showing that a particular approach is or is not a good one. Stories are useful in promoting that a particular approach is the only good one or the only bad one. As a result of these differences, tales are frequently not as complex as stories and tend to be more straightforward with fewer subplots and thematic expansions. Both tales and stories are valid and useful structures, depending upon the intent of the author to either illustrate how a problem was solved with a tale or to argue how to solve a specific kind of problem with a story.