"Harvard takes perfectly good plums as students, and turns them into prunes"

This quote by Frank Lloyd Wright is a criticism of the educational system at Harvard University. He is implying that Harvard takes in trainees who are currently skilled and capable, however then through their educational system, they turn them into something less than they were previously. He is recommending that Harvard's academic system is too rigid and limiting, and that it stifles imagination and originality. He thinks that Harvard's system is too concentrated on conformity and conformity to a certain set of requirements, rather than permitting students to explore their own special talents and abilities. He is suggesting that Harvard's system is too concentrated on producing graduates who are "prunes" instead of "plums". Simply put, Harvard's system is too concentrated on producing graduates who are dull and unoriginal, rather than graduates who are innovative and ingenious.