1689
Context Series · Episode 05

Why They Thought That Way

John Adams said the Revolution happened in the minds of the people fifteen years before a shot was fired at Lexington. This episode goes to the books that produced those minds — the specific texts the founders read, argued about, annotated, and built a republic from. Not summaries. The actual passages, traced to the actual documents they shaped.

Episode Length

~22 minutes

Primary Sources

11 linked documents

Archives

Founders Online · LOC · Avalon Yale · Online Library of Liberty · National Archives

Time Period

1215 – 1776

In 1815, John Adams wrote a letter to Thomas Jefferson in which he asked a question that is still the right question: "What do we mean by the Revolution? The war? That was no part of the Revolution; it was only an effect and consequence of it. The Revolution was in the minds of the people, and this was effected, from 1760 to 1775, in the course of fifteen years before a drop of blood was drawn at Lexington." This episode is about what produced those minds. What they read. What they were taught. And how specific books became specific clauses in specific documents.

The founders did not invent their ideas. They read them — in books, in newspapers, in pamphlets — and then they adapted, argued, synthesized, and applied them to a specific political situation that no author had anticipated. Understanding why the Constitution looks the way it does, why the Declaration says what it says, why the Bill of Rights contains what it contains, requires understanding the library the founders carried with them into the room. This episode opens that library.

01
The Evidence · Donald Lutz · 1984
Who They Actually Cited — The Data

In 1984, political scientist Donald Lutz of the University of Houston published a study in the American Political Science Review — the flagship journal of the discipline — that counted every citation in nearly 15,000 items of American political literature published between 1760 and 1805. He was asking: when the founders made an argument, who did they cite? Whose authority did they invoke? What was the intellectual foundation of the founding era?

The study is titled "The Relative Influence of European Writers on Late Eighteenth-Century American Political Thought." It is the most rigorous data on the founders' reading that exists. Here is what it found.

Authors Most Frequently Cited by the Founders · 1760–1805
Donald S. Lutz · "The Relative Influence of European Writers on Late 18th Century American Political Thought" · American Political Science Review · Vol. 78, No. 1 · 1984 · pp. 189–197
Rank Author / Source Category % of Citations What It Tells Us
#1 The Bible (especially Deuteronomy) Scripture 34% One-third of all citations — predominantly in sermons and political literature alike. Deuteronomy alone was the single most cited text. Note: the Federalists cited the Bible zero times; this is overwhelmingly a sermon literature figure.
#2 Montesquieu — The Spirit of the Laws (1748) Enlightenment 8.3% The most cited secular author. Referenced more often than any individual in the Federalist Papers, where he is called "the celebrated Montesquieu." Source of the separation of powers doctrine and the theory of republican federalism.
#3 Sir William Blackstone — Commentaries on the Laws of England (1765–1769) Common Law 7.9% The legal foundation. Adams and Jefferson both owned multiple editions. Jefferson called it "the most elegant & best digested of our law catalogue." Every lawyer in America learned law from Blackstone before there were American law schools.
#4 John Locke — Two Treatises of Government (1689) Whig Philosophy 2.9% Lower citation rate but outsized philosophical influence. The natural rights framework of the Declaration — life, liberty, and the pursuit of happiness — is directly traceable to Locke's "life, liberty, and property." Jefferson adapted but did not simply copy.
#5 David Hume — Essays (1741–1742) Scottish Enlightenment 2.7% Madison's Federalist No. 10 — the most sophisticated analysis of faction and republican government — draws heavily on Hume's essay "Idea of a Perfect Commonwealth." Madison transformed Hume's skepticism about large republics into an argument for one.
#6 Trenchard & Gordon — Cato's Letters (1720–1723) Radical Whig 1.4% Present in approximately half of all private colonial libraries — the most widely distributed political text in America outside the Bible. Historian Clinton Rossiter called it "the most popular, quotable, esteemed source for political ideas in the colonial period."
Critical note on methodology: The 34% Biblical citation rate is heavily influenced by political sermons — ministers preaching on liberty and governance. When Lutz analyzed only the Federalist and Antifederalist papers — the documents related to constitutional design — the Bible was cited zero times by the Federalists. The intellectual architecture of the Constitution itself drew primarily on Montesquieu, Locke, Blackstone, Hume, and classical antiquity. Both findings are in the same study. Both are true simultaneously. Source: Lutz, American Political Science Review, 1984, p. 194 — the Federalist/Antifederalist breakdown is on that specific page.
02
Most Cited Secular Author · 8.3%
Montesquieu — The Spirit of the Laws · 1748
Primary Text · Most Cited Secular Source in the Founding Era
The Spirit of the Laws
Charles-Louis de Secondat, Baron de Montesquieu · Published 1748 · Available at Avalon Project Yale and Online Library of Liberty

Montesquieu spent twenty years writing The Spirit of the Laws — a massive comparative study of how different forms of government work, why they succeed, and why they fail. Published in 1748 in Geneva, it was banned by the Catholic Church and became one of the most widely read books in the Atlantic world. The founders read it in French and in English translation. Madison, Hamilton, and Jay cited it in the Federalist Papers more than any other secular author. Madison called him "the celebrated Montesquieu" in Federalist No. 47 — a form of citation that assumed the audience already knew exactly who he was.

"When the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty; because apprehensions may arise, lest the same monarch or senate should enact tyrannical laws, to execute them in a tyrannical manner."

Montesquieu · The Spirit of the Laws · Book XI, Chapter 6 · 1748 · Online Library of Liberty →

Where This Appears in the Founding Documents

The separation of powers — Articles I, II, and III of the Constitution, which separate legislative, executive, and judicial power into three distinct branches — is Montesquieu's doctrine, adopted wholesale. Madison cited Montesquieu by name in Federalist No. 47 when explaining why the separation of powers was necessary: "The accumulation of all powers, legislative, executive, and judiciary, in the same hands... may justly be pronounced the very definition of tyranny." He is paraphrasing Montesquieu. Federalism — the idea that a republic could govern a large territory by dividing power between a central government and smaller units — also comes from Montesquieu, who had argued that republics could only survive in small territories. Madison, in Federalist No. 10, turned this argument on its head using Montesquieu's own framework.

Source: Online Library of Liberty · oll.libertyfund.org → · Madison, Federalist No. 47 · avalon.law.yale.edu/18th_century/fed47.asp →

03
The Legal Foundation · 7.9%
Blackstone — Commentaries on the Laws of England · 1765
Primary Text · The Legal Education of Every American Lawyer Before 1800
Commentaries on the Laws of England
Sir William Blackstone · Published 1765–1769 · First American edition Philadelphia, 1771 · Available at Avalon Project Yale

Before Blackstone, English common law existed in a vast, chaotic accumulation of court decisions, statutes, and legal texts that required a lifetime of legal study to navigate. Blackstone organized it into four readable volumes. He published them between 1765 and 1769. The first American edition was published in Philadelphia in 1771 — before the Revolution. Approximately one thousand British copies had already crossed the Atlantic before that. Adams owned annotated copies. Jefferson owned multiple editions and called it "the most elegant and best digested of our law catalogue." Every lawyer in colonial America — and nearly every founder was a lawyer or had studied law — learned their legal framework from this book.

"The absolute rights of man, considered as a free agent, endowed with discernment to know good from evil, and with power of choosing those measures which appear to him to be most desirable, are usually summed up in one general appellation, and denominated the natural liberty of mankind. This natural liberty consists properly in a power of acting as one thinks fit, without any restraint or control, unless by the law of nature."

Blackstone · Commentaries on the Laws of England · Vol. I, Introduction, Section 1 · 1765 · Avalon Project Yale →

Where This Appears in the Founding Documents

The common law tradition in the Constitution — trial by jury (Sixth and Seventh Amendments), protection against unreasonable search and seizure (Fourth Amendment), the right to face accusers — all derive from Blackstone's codification of English common law rights. The founders were not inventing these rights. They were asserting that the English rights Blackstone described applied to Americans — and that Britain had violated them. Jefferson's list of grievances in the Declaration is, in large part, a list of Blackstone violations. The founders used Blackstone's framework to indict the Crown by the Crown's own legal standards.

Source: Avalon Project Yale · avalon.law.yale.edu/18th_century/blackstone.asp → · Bauman Rare Books — Jefferson and Adams on Blackstone ·

04
The Philosophical Foundation · 2.9%
Locke — Two Treatises of Government · 1689
Primary Text · The Natural Rights Foundation of the Declaration
Two Treatises of Government
John Locke · Published 1689 · Available at Online Library of Liberty and Project Gutenberg

Locke published his Two Treatises of Government in 1689 to justify the Glorious Revolution — the overthrow of King James II and the replacement of Stuart absolutism with constitutional monarchy. The Second Treatise — the relevant one — argues that all people are born free and equal, that they possess natural rights to life, liberty, and property, that governments derive their authority from the consent of the governed, and that when governments violate natural rights, the people have the right — the duty — to resist. Jefferson read Locke. The Declaration shows it on every page. But Jefferson did not simply copy Locke. He adapted him — and the adaptation is itself a document.

"The state of nature has a law of nature to govern it, which obliges every one: and reason, which is that law, teaches all mankind, who will but consult it, that being all equal and independent, no one ought to harm another in his life, health, liberty, or possessions."

John Locke · Second Treatise of Government · Chapter II, Section 6 · 1689 · Online Library of Liberty →

The Adaptation — Why Jefferson Changed "Property" to "Pursuit of Happiness"

Locke's phrase was "life, liberty, and property." Jefferson's Declaration reads "life, liberty, and the pursuit of happiness." The change was deliberate. Scholars have debated its meaning for two centuries — the most compelling reading is that Jefferson was expanding Locke's concept: property is a means, not an end; the end is human flourishing, the full development of human potential. Jefferson's phrase is also more universal — "property" excluded those who owned none, while "pursuit of happiness" in principle applied to everyone. The Declaration of the First Continental Congress (1774) had used Locke's original phrase verbatim: "life, liberty, and property." Jefferson's change in 1776 was a considered departure. It is the most studied single word choice in American political history. Jefferson never explained it directly — leaving the interpretation, appropriately, to the people who would live under it.

Source: Online Library of Liberty · oll.libertyfund.org → · Bill of Rights Institute on Locke and Declaration ·

John Locke · Second Treatise of Civil Government · 1689 · Primary text · The foundational source for natural rights theory cited by the founders
oll.libertyfund.org

05
The Popular Voice · In Half of Colonial Libraries
Cato's Letters — Trenchard & Gordon · 1720–1723
Primary Text · The Most Widely Read Political Text in Colonial America
Cato's Letters — Essays on Liberty, Civil and Religious
John Trenchard and Thomas Gordon · Published London Journal 1720–1723 · Collected 1724 · Available at Online Library of Liberty

John Trenchard and Thomas Gordon were English journalists who published 144 essays in the London Journal between 1720 and 1723, writing under the pseudonym "Cato" — after Cato the Younger, the Roman senator who died rather than submit to Julius Caesar. The essays attacked political corruption, government power, religious persecution, and the abuse of liberty with a directness and clarity that Locke's abstract philosophy could not match. Historian Clinton Rossiter called them "the most popular, quotable, esteemed source for political ideas in the colonial period." Collected into bound volumes, they appeared in approximately half of all private libraries in the American colonies — a distribution rate comparable to the Bible itself.

"All men are born free; liberty is a gift which they receive from God himself; nor can they alienate it by their own consent, although they may sell the property of their persons for a season; and no body of men can, without express authority from God, and a violation of natural and civil law, bereave them of it."

Trenchard & Gordon · Cato's Letters · No. 38 · 1721 · Online Library of Liberty →

Why Cato's Letters Mattered More Than Locke to Ordinary Colonists

Locke wrote abstract political philosophy for educated readers. Trenchard and Gordon wrote newspaper columns for everyone who could read — which, in New England, was nearly everyone. They applied Locke's principles to current events: specific government corruption, specific abuses of power, specific violations of liberty. The colonists read them and recognized their own situation — taxation without representation, standing armies, royal governors overriding colonial legislatures. Cato's Letters was the translation layer between abstract philosophy and practical politics. John Adams wrote in his diary that Cato's Letters was among the books that shaped his political thinking. Patrick Henry quoted them. Benjamin Franklin reprinted them. The First Amendment's protection of freedom of speech and press traces directly to arguments Trenchard and Gordon made in the 1720s.

Source: Online Library of Liberty · oll.libertyfund.org → · Adams diary reference · Founders Online → · Cato Institute analysis ·

06
Jefferson · 1771
What They Were Taught to Read — Jefferson's Recommended Library

In 1771, Jefferson wrote a letter to his friend Robert Skipwith recommending a library for "a man of small means." The list he produced — spanning law, politics, history, philosophy, science, and literature — is a primary document showing what an educated Virginia gentleman in the founding era was expected to have read. Jefferson himself had read every item on it. The full letter is at Founders Online.

Jefferson's Recommended Library for "A Man of Small Means" · Letter to Robert Skipwith · August 3, 1771 · Founders Online
Law and Politics
Montesquieu — Spirit of the Laws
Locke — On Government
Algernon Sidney — On Government
Blackstone — Commentaries
Hume — History of England
Bolingbroke — Political Works
Classical Antiquity
Cicero — Offices
Cicero — Tusculan Questions
Seneca
Plutarch — Lives
Epictetus
Marcus Aurelius (Antoninus)
Philosophy and Morality
Locke — Conduct of the Mind in Search of Truth
Locke — On Education
Hume — Essays
Lord Kames — Natural Religion
Voltaire's Works
History and Economics
Steuart — Political Economy
Petty — Political Arithmetic
Montesquieu — Rise and Fall of Rome
Robertson — History
Xenophon — Memoirs of Socrates

The list is not comprehensive — it is what Jefferson considered a minimum for an educated man of modest means. Jefferson's own library was far larger. He donated it twice to Congress — the second donation forming the foundation of the Library of Congress. His personal catalogue included over 6,000 volumes. The reading list for a small library already assumes fluency in Latin, knowledge of English common law, familiarity with French political philosophy, and enough classical education to read Cicero without embarrassment. This was what an educated colonial American was expected to know.

07
Book → Document
Where the Reading Appears in the Founding Documents

The founding documents are not original ideas. They are a synthesis — a translation of European political philosophy into American legal institutions, filtered through the specific experience of the colonial situation. The connections between the books and the documents are traceable, and in many cases the founders made them explicit themselves. Here is the map.

Book → Idea → Founding Document · Primary Source Connections
Montesquieu — Spirit of the Laws, 1748
Separation of legislative, executive, and judicial powers prevents tyranny. Republics require civic virtue. Federal systems can govern large territories.
Constitution: Articles I, II, III. Madison cites Montesquieu by name in Federalist No. 47 and 51. The three-branch structure is Montesquieu's design.
Locke — Two Treatises, 1689
Natural rights to life, liberty, and property. Government by consent of the governed. Right to revolution when government violates natural rights.
Declaration of Independence: "life, liberty, and the pursuit of happiness" (adapted). "Governments are instituted among men, deriving their just powers from the consent of the governed."
Blackstone — Commentaries, 1765
Common law rights of Englishmen: trial by jury, habeas corpus, protection against unreasonable search, right to face accusers, freedom of conscience.
Bill of Rights: Amendments IV, V, VI, VII are direct codifications of the English common law rights Blackstone described. The founders asserted these rights as Americans — and said Britain had violated them.
Cato's Letters — Trenchard & Gordon, 1720
Freedom of speech and press as the foundation of all other liberties. Government power is inherently prone to abuse. Vigilance is the price of liberty.
First Amendment: free speech and press protections trace directly to arguments Trenchard and Gordon made in the 1720s. The phrase "freedom of the press" appeared in Cato's Letters decades before it appeared in any American constitutional document.
Hume — Essays, 1741
Large republics may be more stable than small ones because factions cancel each other out. A multiplicity of interests prevents any one from dominating.
Federalist No. 10 — Madison's argument that a large republic is more stable than a small one directly inverts Montesquieu using Hume's framework. It is the most original intellectual contribution of the founding era.
Cicero — On the Republic, 1st century BC
Natural law above positive law. Mixed constitution balancing monarchy, aristocracy, and democracy. Civic virtue as the foundation of republican government.
The very concept of a "republic" — the word in "United States of America" — is Cicero's. "Res publica" — the public thing, the public matter. The founders saw themselves as reviving Roman republican ideals against the corruption of empire.
Magna Carta · 1215
No person shall be imprisoned or deprived of rights except by lawful judgment of peers or by law of the land. Due process as a legal requirement. Government is not above the law.
Fifth Amendment: "No person shall be... deprived of life, liberty, or property, without due process of law" — direct descent from Magna Carta's Chapter 39. The founders knew this and said so explicitly. Blackstone's Commentaries documented the Magna Carta tradition they were inheriting.
✦ THE RECORD ✦
"

I did not consider it any part of my charge to invent new ideas altogether and to offer no sentiment which had ever been expressed before. My aim was to place before mankind the common sense of the subject, in terms so plain and firm as to command their assent, and to justify ourselves in the independent stand we are compelled to take.

Thomas Jefferson · Letter to Henry Lee · May 8, 1825 · Explaining the Declaration of Independence · Founders Online founders.archives.gov →

Jefferson wrote that in 1825, reflecting on the Declaration he had drafted forty-nine years earlier. He was not inventing new ideas. He was expressing ideas that were already in the minds of the American people — because those people had been reading Locke and Montesquieu and Blackstone and Cato's Letters for two generations. The Revolution, as Adams said, was in the minds of the people before it was in the streets. Those minds had been formed by a specific library. This episode has shown you that library — and where it appears in the documents.

The founders were not prophets. They were readers — extraordinarily well-read, broadly educated, deeply engaged with the political philosophy of their century and the centuries before it. They took what they read, applied it to a specific political crisis, and produced something that had never existed before: a government designed on philosophical principles, written down in plain language, and submitted to the people for ratification. The books made the men. The men made the documents. The documents made the republic.

Go Deeper — Primary Sources and Archives
Every text and document cited in this episode — linked directly to the source
The Press and the Pamphlet — How Print Made the Revolution
Follow the archive on X
@foundersrecord →
Follow the archive
Subscribe · Substack → X · @foundersrecord →