youth and maturity in research

Young researchers do local random jumps in their thinking. In other words, they think of many stupid things and can only see one step ahead. Hence the reason why they need the guidance and filters of the old researchers to stay on track and see which ninety percent of their ideas are actually stupid. 

Mature researchers, on the other hand, do global deterministic jumps in their thinking. Their great knowledge and experience catalyse into a solid style and vision. But while they are flying over the forest, they miss some of the gems hiding among the trees. Hence the reason why they need the young researchers to scavenge for the seeds of new revolutions.