Soseki received private tuition by William Craig, a Shakespeare scholar, whom Soseki described in "Eijitsu Shohin," and developed his theory of literature to be published as "Bungakuron"; however, he was obsessed by the odd feeling about the Japanese studying English literature again and relapsed into nervous breakdown.
『永日小品』にも出てくるシェイクスピア研究家のウィリアム・クレイグの個人教授を受けたり、『文学論』の研究にいそしんだりするが、英文学研究への違和感がぶりかえし神経衰弱に陥り始める。