As Baldwin once observed, language is both “a political instrument, means, and proof of power,” and “the most vivid and crucial key to identity: it reveals the private identity, and connects one with, or divorces one from, the larger, public, or communal identity.”

For Mr. Obama, whose improbable life story many voters regard as the embodiment of the American Dream, identity and the relationship between the personal and the public remain crucial issues. Indeed, “Dreams From My Father,” written before he entered politics, was both a searching bildungsroman and an autobiographical quest to understand his roots — a quest in which he cast himself as both a Telemachus in search of his father and an Odysseus in search of a home.

Like “Dreams From My Father,” many of the novels Mr. Obama reportedly admires deal with the question of identity: Toni Morrison’s “Song of Solomon” concerns a man’s efforts to discover his origins and come to terms with his roots; Doris Lessing’s “Golden Notebook” recounts a woman’s struggles to articulate her own sense of self; and Ellison’s “Invisible Man” grapples with the difficulty of self-definition in a race-conscious America and the possibility of transcendence. The poems of Elizabeth Alexander, whom Mr. Obama chose as his inaugural poet, probe the intersection between the private and the political, time present and time past, while the verse of Derek Walcott (a copy of whose collected poems was recently glimpsed in Mr. Obama’s hands) explores what it means to be a “divided child,” caught on the margins of different cultures, dislocated and rootless perhaps, but free to invent a new self.

This notion of self-creation is a deeply American one — a founding principle of this country, and a trope addressed by such classic works as “The Great Gatsby” — and it seems to exert a strong hold on Mr. Obama’s imagination.

In a 2005 essay in Time magazine, he wrote of the humble beginnings that he and Lincoln shared, adding that the 16th president reminded him of “a larger, fundamental element of American life — the enduring belief that we can constantly remake ourselves to fit our larger dreams.”

Though some critics have taken Mr. Obama to task for self-consciously italicizing parallels between himself and Lincoln, there are in fact a host of uncanny correspondences between these two former Illinois state legislators who had short stints in Congress under their belts before coming to national prominence with speeches showcasing their eloquence: two cool, self-contained men, who managed to stay calm and graceful under pressure; two stoics embracing the virtues of moderation and balance; two relatively new politicians who were initially criticized for their lack of experience and for questioning an invasion of a country that, in Lincoln’s words, was “in no way molesting, or menacing the U.S.”

As Fred Kaplan’s illuminating new biography (“Lincoln: The Biography of a Writer”) makes clear, Lincoln, like Mr. Obama, was a lifelong lover of books, indelibly shaped by his reading — most notably, in his case, the Bible and Shakespeare — which honed his poetic sense of language and his philosophical view of the world. Both men employ a densely allusive prose, richly embedded with the fruit of their reading, and both use language as a tool by which to explore and define themselves. Eventually in Lincoln’s case, Mr. Kaplan notes, “the tool, the toolmaker, and the tool user became inseparably one. He became what his language made him.”

The incandescent power of Lincoln’s language, its resonance and rhythmic cadences, as well as his ability to shift gears between the magisterial and the down-to-earth, has been a model for Mr. Obama — who has said he frequently rereads Lincoln for inspiration — and so, too, have been the uses to which Lincoln put his superior language skills: to goad Americans to complete the unfinished work of the founders, and to galvanize a nation reeling from hard times with a new vision of reconciliation and hope.