Benjamin Franklin, a printer, scientist, diplomat, and political leader of the American Revolution, is presented by Isaacson as the pragmatic and civic-minded heart of the founding generation. Jefferson supplied much of the Declaration’s rhetorical language, whereas Franklin shaped parts of its philosophical framing through revision and editing. His influence on the Declaration of Independence is most famously captured in a single, important edit: changing Jefferson’s phrase “sacred & undeniable” to “self-evident” (7). Isaacson uses this moment to illustrate Franklin’s commitment to grounding the new nation’s principles in reason and natural law instead of theological authority. The change also reflects the broader influence of Enlightenment thought, which emphasized rational inquiry and human reason as foundations for political legitimacy.

Isaacson portrays Franklin as a central figure in the book’s discussion of “common ground.” Long before the Revolution, Franklin was a tireless organizer of civic institutions in Philadelphia, establishing everything from a lending library and a fire brigade to a hospital and an academy. These efforts were driven by his belief that a healthy society depended on citizens voluntarily working together for the common good. Isaacson frames these achievements as the practical application of the ideals later articulated in the Declaration, demonstrating that liberty flourishes when paired with a strong sense of community responsibility.

Franklin’s most significant role in the text is as a symbol of moral evolution, particularly regarding slavery. Isaacson charts Franklin’s journey from a young man who owned enslaved people to an ardent abolitionist in his final years. By the 1770s, Franklin was denouncing the slave trade as a “pestilent detestable traffic in the bodies and souls of men” (16). His later role as president of the Pennsylvania Society for Promoting the Abolition of Slavery and his 1787 petition to Congress become important examples in Isaacson’s argument about the evolving meaning of the Declaration’s principles. Franklin’s changing position allows Isaacson to argue that the language of equality in the Declaration later provided political and moral support for antislavery movements and broader struggles over inclusion and rights.

Thomas Jefferson was the principal author of the Declaration of Independence, a Virginia statesman, and the third US president. Isaacson presents him as the principal writer of the Declaration’s central political ideas, particularly its arguments about equality, rights, and self-government. Drawing heavily from Enlightenment political philosophy, especially the works of John Locke, Jefferson transformed abstract philosophical concepts into memorable political language. As a Deist who believed in a creator while also emphasizing reason and natural law, Jefferson in his original draft emphasized that rights were derived logically “from that equal creation” (19). His soaring and mellifluous prose gave the nation its aspirational language of liberty and equality, establishing the moral and political ideals against which America would measure itself for centuries.

However, Isaacson frames Jefferson as the embodiment of the nation’s central, unresolved contradiction: the gap between its ideals and its reality. While Jefferson wrote that “all men are created equal” (13), he was a lifelong enslaver of more than six hundred people, including Sally Hemings and their children. Isaacson does not shy away from this hypocrisy, noting that Jefferson’s original draft condemned King George III for perpetuating the slave trade, calling it a “cruel war against human nature” (14). Congress later removed this passage from the final Declaration, partly because several colonies remained economically tied to slavery. The removal of the passage highlights the tension between the Declaration’s language of equality and the political compromises surrounding slavery at the time of the Revolution. Isaacson therefore uses Jefferson to illustrate how the nation’s founding ideals coexisted with systems of exclusion and inequality.

Jefferson’s intellectual contributions extended beyond the single sentence. He famously adapted John Locke’s triad of natural rights from “life, liberty, and property” to “Life, Liberty and the pursuit of Happiness” (25). Isaacson interprets this change as broadening the scope of human aspiration beyond mere material acquisition to include individual fulfillment and well-being. He also contrasts Jefferson’s belief in a “natural aristocracy” led by talented individuals with Franklin’s broader emphasis on civic participation and public service. This distinction becomes important in Isaacson’s wider discussion of democracy, opportunity, and inequality in American society.

John Locke was a 17th-century English philosopher whose ideas formed the intellectual foundation of the Declaration of Independence. Isaacson establishes him as the primary source for the Founders’ understanding of natural rights and government. Locke’s Second Treatise of Government (1689) argued that in a “state of nature” (25), all individuals are free and equal and possess inherent rights. He proposed that people form governments through a “social contract” created through the consent of individuals to protect these rights. Isaacson shows how this theory directly informed the Declaration’s assertion that governments derive their “just powers from the consent of the governed” (53).

Locke’s formulation of natural rights as “life, liberty, and property” (25) is central to Isaacson’s analysis. He explains that for Locke, property referred not only to land or wealth but also to ownership of one’s own labor and personhood. Isaacson carefully tracks how Jefferson adapted this concept to the more expansive “pursuit of Happiness” (25). He also returns to Locke’s political philosophy in his discussion of the commons and economic inequality. He highlights the “Lockean Proviso,” Locke’s condition that one can only claim private property from nature if “there is enough, and as good, left in common for others” (28). Isaacson uses this principle to argue that democratic societies require some balance between private opportunity and shared public resources, suggesting this was an important part of the philosophy that shaped America.

John Adams, a lawyer from Massachusetts and a leading voice for independence, served on the five-person committee tasked with drafting the Declaration. Isaacson portrays him as an important influence during the writing process whose political and religious views reflected a more conventional New England outlook. Adams strongly supported independence and republican government, yet his religious beliefs remained closer to traditional Christianity than Jefferson’s Deism. Isaacson suggests Adams was likely responsible for changing Jefferson’s original phrasing to “endowed by their Creator” (61), a revision that introduced a clearer reference to divine authority into the Declaration’s language. Isaacson uses this change to show that the final document drew from Enlightenment political philosophy while also retaining religious language familiar to many 18th-century readers.

Adams also illustrates the limitations of the Founders’ understanding of equality. When his wife, Abigail Adams, urged him to “remember the ladies” (12), he dismissed her concerns, writing back, “I cannot but laugh” (12). Isaacson includes this exchange to demonstrate that the language of “all men” did not extend to women’s political rights during the Revolutionary period. The exchange helps Isaacson show that debates about equality and inclusion were already present at the nation’s founding, even though women remained excluded from formal political participation.

Jean-Jacques Rousseau was a Genevan philosopher whose 1762 work, The Social Contract, was known to Thomas Jefferson and influenced the intellectual climate of the American Revolution. Isaacson introduces Rousseau to deepen the discussion of the first word of the Declaration’s key sentence: “We.” Rousseau’s concept of the “general will” described the collective body of citizens as the source of legitimate political authority. To help explain this idea, Isaacson discusses the Enlightenment belief that governments should derive authority from the people themselves instead of monarchy, hereditary rule, or divine right. Rousseau argued that in forming a society, “Each of us puts his person and all his power in common under the supreme direction of the general will” (5). Isaacson uses this idea to explain how the American colonists increasingly understood themselves as a unified political community with the authority to govern themselves collectively.

David Hume, a leading philosopher of the Scottish Enlightenment, was a close friend and intellectual peer of Benjamin Franklin. Isaacson highlights Hume’s critical contribution to the Declaration through his philosophical distinction between two types of truths, a concept later known as “Hume’s fork.” Hume differentiated between truths known through observation and those that are true by definition, or “discoverable by the mere operation of thought” (8). Isaacson argues that when Franklin changed Jefferson’s wording from “sacred” to “self-evident,” drawing on Hume’s concept of an analytical truth. This philosophical move gave the Declaration’s claims greater authority by presenting them as principles grounded in reason instead of religious assertion or personal belief.

Abigail Adams was the wife of John Adams and an influential commentator on the political and social debates surrounding the American Revolution. Isaacson includes her as an important contemporary voice of conscience who challenged the limitations of the Founders’ revolutionary ideals. Her famous 1776 letter urging her husband to “remember the ladies” (25) in the new nation’s laws is a powerful reminder of the exclusion of women from the promise of equality. Isaacson uses this exchange to show that questions about inclusion and rights emerged alongside the nation’s founding principles rather than appearing only in later historical movements. Abigail Adams also criticized the contradiction between demands for liberty and the continuation of slavery, writing that the “pretensions to liberty are a mockery” (15). By including her critiques, Isaacson demonstrates that the tensions within the Declaration’s language of equality were recognized and challenged during the founding period itself.

George Mason was a Virginia planter and statesman who authored the Virginia Declaration of Rights in June 1776, just before Jefferson drafted the Declaration of Independence. Isaacson presents Mason’s work as the direct precursor and a key source for Jefferson’s more famous document. Mason’s declaration asserted that “all men are by nature equally free and independent, and have certain inherent rights” (52) including “the enjoyment of life and liberty, with the means of acquiring and possessing property, and pursuing and obtaining happiness and safety” (52). Jefferson distilled this language into his more elegant and memorable phrase. Mason’s document also contained a clause that explicitly excluded enslaved people from these protections. Isaacson includes this detail to demonstrate how the language of natural rights existed alongside legal and political efforts to preserve slavery during the founding period. The exclusion reveals how concepts of equality and liberty were shaped by racial and economic limitations despite the universal language used in revolutionary political documents.