Before revision: The decomposition principle is applied by first structuring a simple problem with elements of each level independent of those on succeeding levels, and then working downward from the goal on the top level through criteria bearing on the goal on the second level to sub criteria on the third level, and so on, going from the more general (and sometimes uncertain) to the more particular and concrete.
After revision: I've read the sentencee above and it doesn't tell me whether this is about psychology, military strategy, marriage counseling, ........The decomposition principle is applied by first structuring a simple problem with elements of each level independent of those on succeeding levels, and then working downward from the goal on the top level through criteria bearing on the goal on the second level to sub criteria on the third level, and so on, going from the more general (and sometimes uncertain) to the more particular and concrete.