The hypotheses implicit in this model are:
Problem solving proceeds through a series of stages, from recognition of the problem to resolution, with a statement of the solution sometimes forming a final stage of the process.
ISB results from sub-problems arising at each stage.
Uncertainty is resolved through the ISB acts.
Where uncertainty is not resolved successive searches for information may take place in the same stage and/or the problem solver may return to an earlier stage (not necessarily that immediately before).
The successive search phenomenon (Spink) is explained by this model.