A quote
There is no reason why you should desire to come to me for the sake of making progress. You are mistaken if you think that you will get any assistance from this quarter; it is not a physician that dwells here, but a sick man. I would rather have you say, on leaving my presence: “I used to think him a happy man and a learned one, and I had pricked up my ears to hear him; but I have been defrauded. I have seen nothing, heard nothing which I craved and which I came back to hear.” If you feel thus, and speak thus, some progress has been made. I prefer you to pardon rather than envy my retirement.
Seneca·Letter 68 — On Wisdom and Retirement (§9)·trans. Gummere