Science, Politics, and the Enlightenment
How the new natural philosophy shaped political thought — the idea of natural laws, the cosmic machine as a model of society, and the influence on Locke, Montesquieu, and the democratic revolutions.
Science, Politics, and the Enlightenment
The Scientific Revolution transformed the way Europeans thought about politics. The new natural philosophy suggested that the universe is governed by discoverable, regular laws, and it provided a model of public, reasoned, evidence-based deliberation that was, in turn, applied to the problems of human society. The political theorists of the seventeenth and eighteenth centuries — from Thomas Hobbes and John Locke through Montesquieu and the American and French revolutionaries — drew on the new natural philosophy, sometimes explicitly and sometimes implicitly, in their arguments about the proper organization of political life. The result was a new conception of politics, in which the legitimacy of government was understood to rest not on divine right or inherited tradition but on the consent of the governed, the protection of natural rights, and the rule of law. See How Did the Scientific Revolution Influence the Enlightenment?. The connection between the new science and the modern democratic ideal is examined in What Is the Connection Between Science and Democracy?. And the broader social impact of the Scientific Revolution is set out in The Impact of the Scientific Revolution on Society. For the philosophical background to the new political thought, see The Philosophy of the Scientific Revolution.
The New Cosmology and the New Politics
The new cosmology of the seventeenth century — Copernican in astronomy, Cartesian in natural philosophy, Newtonian in mechanics — was not just a new theory about the natural world. It was also a new way of understanding the relationship between the human being and the cosmos, and it carried with it political implications that were eventually to transform European political life. The first implication was the idea of natural law. The new natural philosophy described a universe governed by regular, mathematical laws, and it suggested that these laws were discoverable by the careful use of human reason. The same idea, applied to the realm of human affairs, suggested that there might be discoverable laws of human nature, and that political life might be improved by the discovery and application of these laws. The natural-law tradition in political thought, which had a long history in medieval and early modern thought, gaven new life and new content by the new natural philosophy. John Locke’s Two Treatises of Government (1689) and Essay Concerning Human Understanding (1690), both written in the generation after Newton’s Principia, drew on the new model of natural law to argue that the purpose of government was the protection of the natural rights of life, liberty, and property. The second implication was the analogy of the cosmic machine to the social machine. The new natural philosophy described the universe as a vast machine, in which the various parts worked together in a regular, law-governed way. The same model, applied to the realm of human affairs, suggested that society might be similarly understood as a machine, in which the various parts — the monarch, the aristocracy, the church, the merchants, the laborers — worked together in a regular, law-governed way. The political theorists of the seventeenth and eighteenth centuries often used the language of mechanism in their political writings, and they often drew explicit analogies between the cosmic machine and the social machine. The third implication was the model of public, reasoned deliberation. The new natural philosophy was conducted in public, in the lecture halls of the new scientific societies, in the pages of the new scientific journals, and in the salons and coffee houses of the new urban culture. The model of public, reasoned deliberation that the new natural philosophy established was, in turn, applied to the problems of human society. The political theorists of the Enlightenment argued that the proper way to settle political questions was by public, reasoned deliberation, rather than by appeal to divine right or inherited tradition. The argument became one of the foundations of modern democratic political thought.
The English Background: Bacon, Hobbes, Locke, Newton
The English contribution to the new political thought of the seventeenth and eighteenth centuries was particularly important. The English scientific revolution — Bacon, Boyle, Hooke, Newton — was accompanied by an English political revolution — the Civil War (1642–1651), the Commonwealth and Protectorate (1649–1660), the Glorious Revolution (1688), the Bill of Rights (1689), and the Act of Settlement (1701) — that established, in the space of half a century, a constitutional monarchy with strong parliamentary institutions. The connection between the two revolutions was not accidental. Francis Bacon, in The Advancement of Learning (1605) and Novum Organum (1620), had made the project of useful knowledge the central program of natural philosophy, and he had insisted that the new knowledge should be made public and applied to the improvement of human life. The political thought of the English Civil War period — the Levellers, the Diggers, the Fifth Monarchists — was influenced by the new philosophy, both directly and indirectly. The political writings of Thomas Hobbes, particularly Leviathan (1651), drew on the mechanical natural philosophy of Galileo and Descartes to argue that political authority rested not on divine right but on the social contract between the sovereign and the subjects. John Locke, who knew Newton personally and was a member of the Royal Society, drew on the new model of natural law in his Two Treatises of Government (1689) and his Essay Concerning Human Understanding (1690). The Essay, in particular, is full of references to the reformed philosophy, and its account of the human understanding as the product of experience owes much to the empirical methods of the new science. The Two Treatises, similarly, draws on the model of natural law to argue that the purpose of government is the protection of the natural rights of life, liberty, and property, and that the people have the right to overthrow a government that fails to fulfill this purpose. The political theory of the American revolutionaries, particularly Thomas Jefferson’s Declaration of Independence (1776), was directly descended from the Lockean tradition.
The French Background: Descartes, Montesquieu, Rousseau
The French contribution to the new political thought of the seventeenth and eighteenth centuries was equally important. The French scientific revolution — Descartes, Mersenne, Pascal, the early Académie des Sciences — was accompanied by a French political revolution — the long conflict between the monarchy and the parlements, the financial crisis of the late eighteenth century, the calling of the Estates-General in 1789, and the French Revolution (1789–1799). The Cartesian natural philosophy, with its mechanical account of the physical world and its insistence on the systematic use of reason, was particularly important for the French political thought of the seventeenth and eighteenth centuries. The political thought of Montesquieu, particularly The Spirit of the Laws (1748), drew on natural philosophy — and on the example of the English constitutional settlement — to argue that the proper organization of government required the separation of powers, with the legislative, executive, and judicial functions distributed among different bodies. The separation of powers, in Montesquieu’s analysis, was a way of ensuring that no single body could accumulate enough power to threaten the liberty of the citizens. The political thought of Jean-Jacques Rousseau, particularly The Social Contract (1762), drew on the new philosophy — and on the example of the Genevan republic — to argue that the proper basis of political authority was the general will of the people, expressed in a social contract. The general will, in Rousseau’s analysis, was the will of the citizens considered as a whole, pursuing the common good. The argument, in turn, became one of the foundations of the French Revolution, and it became one of the foundations of modern democratic political thought.
The American and French Revolutions
The American Revolution (1775–1783) and the French Revolution (1789–1799) were the two great political events of the late eighteenth century, and they were both deeply influenced by the new political thought that had been shaped by the reformed philosophy. The American Declaration of Independence (1776), drafted by Thomas Jefferson, drew directly on the Lockean tradition, and it asserted that the purpose of government is the protection of the natural rights of life, liberty, and the pursuit of happiness. The American Constitution (1787), drafted at the Philadelphia Convention, drew on the Montesquieuian tradition, and it established a system of separated powers and checks and balances. The French Declaration of the Rights of Man and of the Citizen (1789) drew on the Rousseauian tradition, and it asserted the equality of all men in rights. The new natural philosophy was not, of course, the only influence on these political events. The English constitutional tradition, the classical republican tradition, the Protestant religious tradition, and the immediate political circumstances of the late eighteenth century were all important. But natural philosophy provided the conceptual framework in which the new political thought was formulated, and the model of public, reasoned deliberation on which the new political institutions were based.
The Idea of Progress
One of the most important legacies of the Scientific Revolution, in its political dimension, was the idea of progress. The new natural philosophy suggested that the careful study of nature could produce reliable knowledge, and that this knowledge could be applied to the improvement of human life. The same idea, applied to the realm of human affairs, suggested that the careful study of human society could produce reliable knowledge, and that this knowledge could be applied to the improvement of political life. The result was a new conception of history, in which the human race was understood to be making progress, slowly but steadily, from a primitive state to a more civilized one. The idea of progress gaven classic expression in the works of the French philosophes — Turgot, Condorcet, and the contributors to the Encyclopédie — and in the works of the Scottish Enlightenment — David Hume, Adam Smith, Adam Ferguson. The idea, in turn, became one of the central concepts of the political thought of the nineteenth and twentieth centuries, and it remains one of the central concepts of modern political discourse.
The Limits of the New Political Thought
The new political thought of the seventeenth and eighteenth centuries was not, of course, without its limits. The natural-law arguments that were used to justify the rights of man were sometimes also used to justify the natural subordination of women, the natural inferiority of non-European peoples, and the natural authority of the educated classes. The Rousseauian argument for the general will would be used to justify the totalitarian politics of the twentieth century. The Lockean argument for the protection of property would be used to justify the inequalities of the industrial age. The new political thought was, in short, a mixed legacy. The same arguments that were used to support the rights of man were also used to support the privileges of the few. The same model of public, reasoned deliberation that was used to support the democratic revolutions was also used to support the imperial ventures of the eighteenth and nineteenth centuries. The Scientific Revolution, in its political dimension, was not a simple story of progress. It was a complex story, in which the new ideas were used for a wide range of purposes, some of which we would now regard as admirable and some of which we would now regard as reprehensible. See How Did the Scientific Revolution Influence the Enlightenment?. The connection between the new science and the modern democratic ideal is examined in What Is the Connection Between Science and Democracy?. And the broader social impact of the Scientific Revolution is set out in The Impact of the Scientific Revolution on Society.