Henri Matisse said: “You study, you learn, but you guard the original naïveté. It has to be within you, as desire for drink is within the drunkard or love is within the lover.”
(Taking the point further, Lady Bracknell does “not approve of anything which tampers with natural ignorance. Ignorance is like a delicate, exotic fruit. Touch it, and the bloom is gone!”)
I have to agree with Matisse. Naïveté, or to be more precise, naive enjoyment and wonder, do need to be guarded against the erosions of study and learning. Study and learning add immeasurably to understanding, but they do sometimes threaten joy, which ought to be a primary goal of art.
Robert Pippin writes a Defence of Naïve Reading in the NY Times blog, which makes the point more emphatically. Excessive learning, particularly where it strays into the worst kinds of self-indulgent theorising, detracts from the simple pleasure of reading, so that it's no wonder students aren't attracted in the numbers they were to tertiary courses in literature or writing. The teachers I learned most from at university were those that gave me knowledge without taking away pleasure. Pleasure increased as knowledge increased. Indeed pleasure was understood as that Hesperidian island towards which we were sailing, not merely a by-product of our interest in boats.