Molly Young at the New York Times:
In her theory of writing, Ferrante stands opposed to someone like Joan Didion. Didion famously insisted that she wrote in order to find out what she thought. (“Had I been blessed with even limited access to my own mind there would have been no reason to write.”) In Ferrante’s case, the act is a flawed transcription of what she calls “the brain wave.” For Didion, everything was gained in the voyage from mind to pen; for Ferrante, much goes missing.
As much as “In the Margins” is a philosophical monograph on the nature of writing, it is also a practical manual. Ferrante furnishes tips. She doesn’t present them as such — there’s no prescription, only an outline of what she’s learned and how it’s helped her (and by implication, how it might help anyone else).