Pierian spring

A little Learning is a dang'rous Thing; Drink deep, or taste not the Pierian Spring.

At school I enjoyed the inestimable advantage of a very sensible, though at the same time, a very severe master. […] [H]e showed no mercy to phrase, metaphor, or image, unsupported by a sound sense, or where the same sense might have been conveyed with equal force and dignity in plainer words. […] In fancy I can almost hear him now, exclaiming "Harp? Harp? Lyre? Pen and ink, boy, you mean! Muse, boy, Muse? Your Nurse's daughter, you mean! Pierian spring? Oh 'aye! the cloister-pump, I suppose!"

[…] a studious land Where humming youth, intent upon the page, Thirsting for knowledge with a noble rage, Drink dry the whole Pierian spring

For him the library represented a Pierian spring, that metaphorical source of knowledge and inspiration. He drew deeply there, quelling his intellectual insecurities and nourishing his fanatic ambitions.