John Locke in the context of "Soviet democracy"

The Age of Enlightenment (also the Age of Reason) was a period in the history of Europe and Western civilization during which the Enlightenment, an intellectual and cultural movement, flourished, emerging in the late 17th century in Western Europe and reaching its peak in the 18th century, as its ideas spread more widely across Europe and into the European colonies, in the Americas and Oceania. Characterized by an emphasis on reason, empirical evidence, and scientific method, the Enlightenment promoted ideals of individual liberty, religious tolerance, progress, and natural rights. Its thinkers advocated for constitutional government, the separation of church and state, and the application of rational principles to social and political reform.

The Enlightenment emerged from and built upon the Scientific Revolution of the 16th and 17th centuries, which had established new methods of empirical inquiry through the work of figures such as Galileo Galilei, Johannes Kepler, Francis Bacon, Pierre Gassendi, Christiaan Huygens and Isaac Newton. Philosophical foundations were laid by thinkers including René Descartes, Thomas Hobbes, Baruch Spinoza, and John Locke, whose ideas about reason, natural rights, and empirical knowledge became central to Enlightenment thought. The dating of the period of the beginning of the Enlightenment can be attributed to the publication of Descartes' Discourse on the Method in 1637, with his method of systematically disbelieving everything unless there was a well-founded reason for accepting it, and featuring his dictum, Cogito, ergo sum ('I think, therefore I am'). Others cite the publication of Newton's Principia Mathematica (1687) as the culmination of the Scientific Revolution and the beginning of the Enlightenment. European historians traditionally dated its beginning with the death of Louis XIV of France in 1715 and its end with the outbreak of the French Revolution in 1789. Many historians now date the end of the Enlightenment as the start of the 19th century, with the latest proposed year being the death of Immanuel Kant in 1804.

David Hume (/hjuːm/; born David Home; 7 May 1711 – 25 August 1776) was a Scottish philosopher, historian, economist and essayist who is known for his highly influential system of empiricism, philosophical scepticism and metaphysical naturalism. Beginning with A Treatise of Human Nature (1739–40), Hume strove to create a naturalistic science of man that examined the psychological basis of human nature. Hume followed John Locke in rejecting the existence of innate ideas, concluding that all human knowledge derives solely from experience; this places him amongst such empiricists as Francis Bacon, Thomas Hobbes, John Locke, and George Berkeley.

Hume argued that inductive reasoning and belief in causality cannot be justified rationally; instead, they result from custom and mental habit. People never actually perceive that one event causes another but only experience the "constant conjunction" of events. This problem of induction means that to draw any causal inferences from past experience, it is necessary to presuppose that the future will resemble the past; this metaphysical presupposition cannot itself be grounded in prior experience.

In political science, legitimacy is a concept concerning the right of an authority, usually a governing law or a regime, to rule the actions of a society. In political systems where this is not the case, unpopular regimes survive because they are considered legitimate by a small, influential elite. In Chinese political philosophy, since the historical period of the Zhou dynasty (1046–256 BC), the political legitimacy of a ruler and government was derived from the Mandate of Heaven, and unjust rulers who lost said mandate therefore lost the right to rule the people.

In moral philosophy, the term legitimacy is often positively interpreted as the normative status conferred by a governed people upon their governors' institutions, offices, and actions, based upon the belief that their government's actions are appropriate uses of power by a legally constituted government.

An essay (/ˈɛs.eɪ/, ESS-ay) is, generally, a piece of writing that gives the author's own argument, but the definition is vague, overlapping with those of a letter, a paper, an article, a pamphlet, and a short story. Essays have been sub-classified as formal and informal: formal essays are characterized by "serious purpose, dignity, logical organization, length," whereas the informal essay is characterized by "the personal element (self-revelation, individual tastes and experiences, confidential manner), humor, graceful style, rambling structure, unconventionality or novelty of theme," etc.

Essays are commonly used as literary criticism, political manifestos, learned arguments, observations of daily life, recollections, and reflections of the author. Almost all modern essays are written in prose, but works in verse have been dubbed essays (e.g., Alexander Pope's An Essay on Criticism and An Essay on Man). While brevity usually defines an essay, voluminous works like John Locke's An Essay Concerning Human Understanding and Thomas Malthus's An Essay on the Principle of Population are counterexamples.

In philosophy, rationalism is the epistemological view that "regards reason as the chief source and test of knowledge" or "the position that reason has precedence over other ways of acquiring knowledge", often in contrast to other possible sources of knowledge such as faith, tradition, or sensory experience. More formally, rationalism is defined as a methodology or a theory "in which the criterion of truth is not sensory but intellectual and deductive".

In a major philosophical debate during the Enlightenment, rationalism (sometimes here equated with innatism) was opposed to empiricism. On the one hand, rationalists like René Descartes emphasized that knowledge is primarily innate and the intellect, the inner faculty of the human mind, can therefore directly grasp or derive logical truths; on the other hand, empiricists like John Locke emphasized that knowledge is not primarily innate and is best gained by careful observation of the physical world outside the mind, namely through sensory experiences. Rationalists asserted that certain principles exist in logic, mathematics, ethics, and metaphysics that are so fundamentally true that denying them causes one to fall into contradiction. The rationalists had such a high confidence in reason that empirical proof and physical evidence were regarded as unnecessary to ascertain certain truths – in other words, "there are significant ways in which our concepts and knowledge are gained independently of sense experience".

Foundationalism concerns philosophical theories of knowledge resting upon non-inferential justified belief, or some secure foundation of certainty such as a conclusion inferred from a basis of sound premises. The main rival of the foundationalist theory of justification is the coherence theory of justification, whereby a body of knowledge, not requiring a secure foundation, can be established by the interlocking strength of its components, like a puzzle solved without prior certainty that each small region was solved correctly.

Identifying the alternatives as either circular reasoning or infinite regress, and thus exhibiting the regress problem, Aristotle made foundationalism his own clear choice, positing basic beliefs underpinning others. Descartes, the most famed foundationalist, discovered a foundation in the fact of his own existence and in the "clear and distinct" ideas of reason, whereas Locke found a foundation in experience. Differing foundations may reflect differing epistemological emphases—empiricists emphasizing experience, rationalists emphasizing reason—but may blend both.

Liberalism is a political and moral philosophy based on the rights of the individual, liberty, consent of the governed, political equality, right to private property, and equality before the law. Liberals espouse various and sometimes conflicting views depending on their understanding of these principles but generally support private property, market economies, individual rights (including civil rights and human rights), liberal democracy, secularism, rule of law, economic and political freedom, freedom of speech, freedom of the press, freedom of assembly, and freedom of religion. Liberalism is frequently cited as the dominant ideology of modern history.

Liberalism became a distinct movement in the Age of Enlightenment, gaining popularity among Western philosophers and economists. Liberalism sought to replace the norms of hereditary privilege, state religion, absolute monarchy, the divine right of kings and traditional conservatism with representative democracy, rule of law, and equality under the law. Liberals also ended mercantilist policies, royal monopolies, and other trade barriers, instead promoting free trade and marketization. The philosopher John Locke is often credited with founding liberalism as a distinct tradition based on the social contract, arguing that each man has a natural right to life, liberty and property, and governments must not violate these rights. While the British liberal tradition emphasized expanding democracy, French liberalism emphasized rejecting authoritarianism and is linked to nation-building.

An unobservable (also called impalpable) is an entity whose existence, nature, properties, qualities or relations are not directly observable by humans. In philosophy of science, typical examples of "unobservables" are the force of gravity, causation and beliefs or desires. The distinction between observable and unobservable plays a central role in Immanuel Kant's distinction between noumena and phenomena as well as in John Locke's distinction between primary and secondary qualities. There is considerable disagreement about which objects should be classified as unobservable, for example, whether bacteria studied using microscopes or positrons studied using cloud chambers count as unobservable. Different notions of unobservability have been formulated corresponding to different types of obstacles to their observation.

The separation of church and state is a philosophical and jurisprudential concept for defining political distance in the relationship between religious organizations and the state. Conceptually, the term refers to the creation of a secular state (with or without legally explicit church-state separation) and to disestablishment, the changing of an existing, formal relationship between the church and the state. The concept originated among early Baptists in America. In 1644, Roger Williams, a Baptist minister and founder of the state of Rhode Island and the First Baptist Church in America, was the first public official to call for "a wall or hedge of separation" between "the wilderness of the world" and "the garden of the church." Although the concept is older, the exact phrase "separation of church and state" is derived from "wall of separation between Church & State," a term coined by Thomas Jefferson in his 1802 letter to members of the Danbury Baptist Association in the state of Connecticut. The concept was promoted by Enlightenment philosophers such as John Locke.

In a society, the degree of political separation between the church and the civil state is determined by the legal structures and prevalent legal views that define the proper relationship between organized religion and the state. The arm's length principle proposes a relationship wherein the two political entities interact as organizations each independent of the authority of the other. The strict application of the secular principle of laïcité is used in France. In contrast, societies such as Denmark and England maintain the constitutional recognition of an official state church; similarly, other countries have a policy of accommodationism, with religious symbols being present in the public square.