The vacation phrase "getting back to nature" implies we've been there before. Paul Lehmberg would probably take the phrase literally: In this, his first book, he returns to the territory where he once guided canoeists and trained Outward Bounders. British novelist John Fowles ("The Magus," "The French Lieutenant's Woman") takes nothing literally. In light of his mesmerizing essay -- a strange bedfellow for Frank Horvat's murky, disappointing photographs -- the phrase is redolent of one of mankind's profoundest problems.

First, the literal interpretation. "In the Strong Woods" resulted from a summer that Lehmberg, estranged from his wife, spent virtually alone in a cabin on Lake Nym, in Ontario. ("Strong" in the title is defined by the Oxford English Dictionary as "of country: thickly covered with undergrowth.") It is a book of reflections -- on travel, housework, timekeeping, and solitude. With such an approach a great deal depends on the author's tone and style. Lehmberg succeeds in both categories: He is an engaging fellow to spend time with, and he writes lively, sensuous prose. Let him speak for himself, in a passage about baking bread.

"Forty minutes after the second rising I find dark jewels hidden in the blackness of the oven, and I can never wait for the rough-crusted loaves to cool. As soon as I have them out of their pans, I slice two slabs of the steaming bread from off a loaf-end and cut a flat wedge from the wheel of cheese. It is exquisite food, this smooth sharp cheese, as ripe and smoky yellow as a full moon floating on a snowfield, and this coarse bread, dark and sweetly flavored with molasses and honey, to which it is joined. Such food is exquisitely and especially fit for the man who made it, as it cannot help but be. Each piece of bread is seeded with the remembrance of my making it, which so educates, so refines and shapens my palate that there can be no more discriminating taster of this food than myself."

But for all its yeastiness, "In the Strong Woods" comes out slightly flat. The let-down has to do with Lehmberg's decision to limit his presence in his book. Without asking him to bare his psychic wounds, the reader can rightly expect him at least to tell whether he and his wife wrote to one another over the summer and whether they got back together. Silent on these points, Lehmberg seems to have skirted the strongest copses in his woods.

No such reticence hamstrings John Fowles. His essay is personal and idiosyncratically discursive. It adopts as its central image the small, formal garden kept by Carl Linnaeus, the 18th-century originator of the international system for classifying plants and animals. The garden is extant, in Uppsala, Sweden, and Fowles views its meticulous order as symbolic of its creator's selective and narrowing approach to nature. Influenced by Linnaeus, [a] great deal of science is devoted to . . . providing specific labels, explaining specific mechanisms and ecologies, in short for sorting and tidying what seems in the mass indistinguishable one from the other. Even the simpliest knowledge of the names and habits of flowers or trees starts from this distinguishing or individuating process, and removes us a step from total reality toward anthropomorphism . . . [This knowledge] destroys or curtails certain possibilities of seeing, apprehending and experiencing. And that is the bitter fruit from the tree of Uppsalan knowledge." Fowles consider this naming approach to nature as symptomatic of a disease, the compuslion to acquire nature, to "use it in some way, to derive some personal yield," whereas in fact much of nature is characterized by "general uselessness."

So far so good. Indeed, so commonplace: poets have been rebelling against the purely scientific attitude toward nature for generations. It has been more than a hundred years since Walt Whitman got "tired and sick" of the "learn'd astronomer" with his proofs and columns of figures. But Fowles takes us out of the garden and deep into the woods. There we find something unexpected -- an aspect of ourselves. In each of us, Fowles claims, there is a green man, a wild side, a capacity to experience nature not in the manner of a naming, measuring scientist but of a feeling, embracing artist. "There is something in the nature of nature, in its presentness, its seeming transcience [sic], its creative ferment and hidden potential, that corresponds very closely with the wild, or green man, in our psyches . . ." (This green man of the mind is akin to the reptillian component of the human brain which Carl Sagan elucidates in "The Dragons of Eden.")

Out increasing alienation from nature, Fowles believes, bespeaks our more fundamental alienation from the wild part of ourselves, the depths that we perforce return to in dreams, the source of esthetic impulses. "There is a spiritual corollary to the way we are currently deforesting and denaturing our planet," Fowles writes. "In the end what we must most defoliate and deprive is ourselves. We might as soon start collecting up the world's poetry, every line and every copy, to burn it in a final pyre; and think we should lead richer and happier lives thereafter." In what is both a striking display of empathy for nature and the most original argument for wilderness preservation that I have encountered, John Fowles regards the deforestation of the earth as a threat to the well-being of art.