After reading and analyzing "The Thought-Fox," it's easy to see why the image of a fox emerging from the edge of a dark forest is similar to an idea developing and surfacing from the depths of a writer's mind. The fox's manner—sneaky, clever, bold— echoes the way which an inspiration can suddenly strike, while the forest's setting—dark, dense, deep—is much like a writer's imagination. But the qualities the fox exhibits are also apparent in other animals who creep around the forest at night. A cat on the prowl, for example, would fit the bill, too. So why a fox?
The answer to this question lies in a dream Hughes had one night during his first year at Cambridge. In his article "Ted Hughes' 'The Thought-Fox': Object, Symbol, and Creativity," Bibhu Padhi quotes poet W.S. Merwin, who once relayed Hughes' story of this dream. According to Hughes and Merwin, Hughes dreamt he "Saw [his] door open and someone like himself [came] in with a fox's head. The visitor went over to his desk, where an unfinished essay was lying, put his paws on the papers, leaving a bloody mark." This dream figure then told Hughes "You're killing me," and left.
At the time, Hughes was pursuing English literature. Following this dream, he decided to study Anthropology and Archaeology instead, two fields which corresponded to his interests in folklore, mythology, and the natural world. While this switch may seem contrary to a young poet's goals, these disciplines fueled his creativity, allowing Hughes to seriously pursue the possibilities lying in subjects that first captured his attention during his childhood.
Specifically, the animal world fascinated Hughes from a young age. In an interview with Drue Heinz for the Spring 1995 issue of The Paris Review, Hughes recalled the role that the natural world played in his childhood, citing his Yorkshire upbringing as a crucial element in his creative development. "When I came to consciousness," he remembered, "my whole interest was in wild animals." He also said that "up to the age of seventeen or eighteen, shooting and fishing and my preoccupation with animals were pretty well my life, apart from books." The natural world's complicated character—gentle but unforgiving, violent but generative, fertile but filled with decay—combined with literature proved an enduring poetic match throughout Hughes' career.
Considering that "The Thought-Fox" appears in The Hawk and The Rain, Hughes' first collection, the poem resonates more powerfully as the work of a young poet coming into his own, exploring his own mind's forest, teasing the possibilities of what lurks within. Because Hughes' fateful dream established a connection between the poet and the fox's image and character, it's not a far reach to equate the speaker of "The Thought-Fox" with Hughes and the animal lurking near the forest with the sudden shock of the fox-figure in Hughes' dream. Hughes' dream forced him to acknowledge and act upon a feeling he already knew to be true: abandoning the academic realm of literary studies for the world of folklore, mythology, and mysticism would best benefit his poetry.