Theodore Levitt
'Knowledge is peculiar. It has the special quality of enriching those who receive it without impoverishing or diminishing those who give it away. But the most precious of all knowledge can be neither taught nor passed on. . . . The most important thing is the general manager knows and does involve that kind of knowledge--inherent, authentic, and resistant to teachability but not to learnability'.--from Chapter 3, 'Management and Knowledge'.