Two Distinct Kinds of Proficiency
"Every systematic science, the humblest and the noblest alike, seems to admit of two distinct kinds of proficiency; one which is referred to as scientific knowledge of the topic, while the other is a kind of educational familiarity with it. For an educated individual should be able to form a fair off-hand judgment as to the effectiveness or ineffectiveness of the method used by a teacher in his lecture.
To be educated is in fact to have the ability to do this; and even the man of universal education we deem to be virtuous in having this kind of ability. It will, however, be certainly understood that we only attribute universal education to one who in his own individual self is critical in all or almost all branches of knowledge, and not to an individual who has a similar ability only in one particular special area of knowledge. It is possible for an individual to have this ability in a single particular branch of knowledge without possessing it in all."
Aristotle, On the Parts of Animals