The kind of difficult problems with which he is concerned, are those where knowledge driven thinking fails because the obvious area to search for the solution is not where it is found . The breakthrough originates with a precipitating event which is often fortuitous as when it is triggered by some external circumstance which cues the moment. According to Perkins, the precipitating event for both Wallace and Darwin was their reading of Malthus's Essay on the Principle of Population . After providing a number of examples of breakthrough thinking and problem solving, Perkins goes on to draw an analogy between the nature, structure, and logic of breakthrough thinking and evolutionary processes. He describes evolution as a kind of search.
Evolution follows the path of a long search for viable forms.
Occasionally an event will produce a rapid breakthrough which will result in a transformation of the species. Perkin's perspective on the nature and structure of evolutionary change follows closely that of Stephen J Gould, to whom he refers on several occasions in his development of the parallel between intellectual and evolutionary problem solving. His paradigm example is that of the feather covered dinosaurs that eventually evolved into birds. The evolutionary story, which he admits may or may not be true, nevertheless reflects the five step pattern. Some species of smaller dinosaurs would have evolved feathers as insulation.