The correct assumption is that what individuals have learned by age twenty-one will begin to become obsolete five to ten years later and will have to be replaced-or at least refurbished-by new learning, new skills, new knowledge.
Peter DruckerThe knowledge we now consider knowledge proves itself in action. What we now mean by knowledge is information effective in action, information focused on results. Results are outside the person, in society and economy, or in the advancement of knowledge itself. To accomplish anything this knowledge has to be highly specialized.
Peter Drucker