An important symbol is set up by Cooper at the beginning of Chapter 1 of The Pathfinder. The mystique surrounding Natty Bumpo because of his "great purity of character, and ... marked peculiarities" depends upon the expansiveness of his presence, which is what allows him have singular focus on his responsibilities for people's safety in the frontier. This sense of expansiveness and singularity is symbolically established in the first lines that speak of the sublime vast void:
The sublimity connected with vastness is familiar to every eye. The most abstruse, the most far-reaching, perhaps the most chastened of the poet's thoughts, crowd on the imagination as he gazes into the depths of the illimitable void.
In this symbol also rests the thing that once lost causes Natty to act contrary to his nature, to endanger people's lives, and to cause Dunham the loss of his life. This other element of the symbol is the isolation from human emotion and intimacy that must accompany Natty's expansiveness and singularity. When he falls in love with Mabel, he steps out of the isolation, which proves to be costly for those for whom he is responsible. Natty feels his failure and regrets the distraction of love and the ill consequences that resulted. Afterward, Natty reclaims his position in a vast expanse of a void and in so doing also reclaims his place as “the most renowned hunter of that portion of the state.”
The same quote serves to illustrate an image Cooper conjures up, that of illimitable vastness, but another equally descriptive image is offered in the first chapter--an image therefore central to the mood (or atmosphere) Cooper wants to establish for the novel. The scene is the encounter with trees piled upon each other so high as to "ascend to an elevation of some thirty feet above the level of the earth." Cooper's narrator creates an image of these trees by describing their "vast trunks" as "broken and driven by the force of a gust" of wind and as "interlaced" and having "their branches still exhaling the fragrance of withering leaves."