Cartesian doubt

Cartesian Doubt is a form of methodological skepticism associated with the writings and methodology of René Descartes (March 31,1596–Feb 11, 1650).[1][2] Cartesian doubt is also known as Cartesian skepticism, methodic doubt, methodological skepticism, universal doubt, systematic doubt or hyperbolic doubt.

Cartesian doubt is a systematic process of being skeptical about (or doubting) the truth of one's beliefs, which has become a characteristic method in philosophy. Additionally, Descartes' method has been seen by many as the root of the modern scientific method. This method of doubt was largely popularized in Western philosophy by René Descartes, who sought to doubt the truth of all his beliefs in order to determine which beliefs he could be certain were true. It is the basis for Descartes' statement, "Cogito ergo sum" ("I think, therefore I am"). Of course, Descartes never actually wrote "cogito ergo sum,' instead, he wrote in his native French, "Je pense, donc je suis."

Methodological skepticism is distinguished from philosophical skepticism in that methodological skepticism is an approach that subjects all knowledge claims to scrutiny with the goal of sorting out true from false claims, whereas philosophical skepticism is an approach that questions the possibility of certain knowledge.


Cartesian doubt is methodological. Its purpose is to use doubt as a route to certain knowledge by finding those things which could not be doubted. The fallibility of sense data in particular is a subject of Cartesian doubt.

There are several interpretations as to the objective of Descartes' skepticism. Prominent among these is a foundationalist account which claims that Descartes' skepticism is aimed at eliminating all belief which it is possible to doubt, thus leaving Descartes with only basic beliefs (also known as foundational beliefs). From these indubitable basic beliefs, Descartes then attempts to derive further knowledge. It's an archetypal and significant example that epitomizes the Continental Rational schools of philosophy.


Descartes' method of hyperbolic doubt included:

  1. accepting only information you know to be true
  2. breaking down these truths into smaller units
  3. solving the simple problems first
  4. making complete lists of further problems

Hyperbolic doubt means having the tendency to doubt, since it is an extreme or exaggerated form of doubt.[3] (Knowledge in the Cartesian sense means to know something beyond not merely all reasonable, but all possible, doubt.) In his Meditations on First Philosophy (1641), Descartes resolved to systematically doubt that any of his beliefs were true, in order to build, from the ground up, a belief system consisting of only certainly true beliefs; his end goal—or a major one, at the least—was to find an undoubtable basis for the sciences. Consider Descartes' opening lines of the Meditations:

Several years have now elapsed since I first became aware that I had accepted, even from my youth, many false opinions for true, and that consequently what I afterward based on such principles was highly doubtful; and from that time I was convinced of the necessity of undertaking once in my life to rid myself of all the opinions I had adopted, and of commencing anew the work of building from the foundation...

— René Descartes, Meditation I, 1641

Descartes' method

René Descartes, the originator of Cartesian doubt, put all beliefs, ideas, thoughts, and matter in doubt. He showed that his grounds, or reasoning, for any knowledge could just as well be false. Sensory experience, the primary mode of knowledge, is often erroneous and therefore must be doubted. For instance, what one is seeing may very well be a hallucination. There is nothing that proves it cannot be. In short, if there is any way a belief can be disproved, then its grounds are insufficient. From this, Descartes proposed two arguments, the dream and the demon.[4]

The dream argument

Descartes, knowing that the context of our dreams, while possibly unbelievable, are often lifelike, hypothesized that humans can only believe that they are awake. There are no sufficient grounds by which to distinguish a dream experience from a waking experience. For instance, Subject A sits at the computer, typing this article. Just as much evidence exists to indicate that the act of composing this article is reality as there is evidence to demonstrate the opposite. Descartes conceded that we live in a world that can create such ideas as dreams. However, by the end of The Meditations, he concludes that we can distinguish dream from reality at least in retrospect:[2]

"But when I distinctly see where things come from and where and when they come to me, and when I can connect my perceptions of them with my whole life without a break then I can be certain that when I encounter these things I am not asleep but awake."

— Descartes: Selected Philosophical Writings[5]

The Evil Demon

Descartes reasoned that our very own experience may very well be controlled by an evil demon of sorts.[6] This demon is as clever and deceitful as he is powerful. He could have created a superficial world that we may think we live in.[2] As a result of this doubt, sometimes termed the Malicious Demon Hypothesis, Descartes found that he was unable to trust even the simplest of his perceptions.

In Meditation I, Descartes stated that if one were mad, even briefly, the insanity might have driven man into believing that what we thought was true could be merely our minds deceiving us. He also stated that there could be 'some malicious, powerful, cunning demon' that had deceived us, preventing us from judging correctly.

Descartes argued that all his senses were lying and since your senses can easily fool you, his idea of an infinitely powerful being must be true as that idea could have only been put there by an infinitely powerful being which would have no reason to be deceitful to him.

I think, therefore I am

While methodic doubt has a nature, one need not hold that knowledge is impossible in order to apply the method of doubt. Indeed, Descartes' attempt to apply the method of doubt to the existence of himself spawned the proof of his famous saying, "Cogito, ergo sum" (I think, therefore I am). That is, Descartes tried to doubt his own existence, but found that even his doubting showed that he existed, since he could not doubt if he did not exist.[2]

See also


  1. ^ "A Philosophical Glossary" edited by Justin Leiber, Philosophy Department, University of Houston, USA.
  2. ^ a b c d Roger Scruton. Modern Philosophy: An Introduction and Survey. London: Penguin Books, 1994.
  3. ^ Skirry (2006).
  4. ^ Scruton, R. (2012). Modern Philosophy: An Introduction and Survey. Bloomsbury Publishing. ISBN 978-1-4482-1051-0. Retrieved 2019-06-06.
  5. ^ Descartes, René (1988-02-26). Descartes: Selected Philosophical Writings. Cambridge University Press. ISBN 9780521358125.
  6. ^ Revonsuo, A., Consciousness: The Science of Subjectivity (Milton Park: Taylor & Francis, 2010), pp. 50–52.

Further reading

  • Cottingham, Stoothoff, and Murdoch (eds.). (1984). The Philosophical Writings of Descartes. Cambridge: Cambridge University Press.
  • Janet Broughton, Descartes's Method of Doubt, Princeton University Press, 2002.
  • Edwin M. Curley, Descartes against the Skeptics, Harvard University Press, 1978.

External links

Charles Cooley

Charles Horton Cooley (August 17, 1864 – May 7, 1929) was an American sociologist and the son of Michigan Supreme Court Judge Thomas M. Cooley. He studied and went on to teach economics and sociology at the University of Michigan, was a founding member of the American Sociological Association in 1905 and became its eighth president in 1918. He is perhaps best known for his concept of the looking glass self, which is the concept that a person's self grows out of society's interpersonal interactions and the perceptions of others. Cooley's health began to deteriorate in 1928. He was diagnosed with an unidentified form of cancer in March of 1929 and died two months later.alex

Dark Star (film)

Dark Star is a 1974 American science fiction comedy film directed by John Carpenter and co-written with Dan O'Bannon. It follows the crew of the deteriorating starship Dark Star, twenty years into their mission to destroy unstable planets that might threaten future colonization of other planets.

Beginning as a University of Southern California student film produced from 1970 to 1972, the film was gradually expanded to feature film length by 1974, when it appeared at Filmex before receiving a limited theatrical release in 1975. Its final budget is estimated at $60,000. While initially unsuccessful with audiences, it was relatively well received by critics and continued to be shown in theaters as late as 1980. The home video revolution of the early 1980s helped the film achieve "cult classic" status, and O'Bannon collaborated with home video distributor VCI in the production of multiple versions on VHS, Laserdisc, and DVD.

The feature film debut for both Carpenter and O'Bannon, it was also produced and scored by Carpenter, while O'Bannon also acted as editor, production designer, and visual effects supervisor and appeared as Sergeant Pinback.

De omnibus dubitandum est

De omnibus dubitandum est is a book written by Søren Kierkegaard (under the pseudonym Johannes Climacus), which translates to "everything must be doubted". It was published posthumously. The book portrays the existential consequences of assuming Cartesian doubt, the method of modern philosophy, to its last consequences. The themes portrayed by this book are followed in the subsequent books written by Kierkegaard under the name of Climacus: Philosophical Fragments and its Concluding Unscientific Postscript.


Doubt is a mental state in which the mind remains suspended between two or more contradictory propositions, unable to assent to any of them. Doubt on an emotional level is indecision between belief and disbelief. It may involve uncertainty, distrust or lack of conviction on certain facts, actions, motives, or decisions. Doubt can result in delaying or rejecting relevant action out of concern for mistakes or missed opportunities.

Dream argument

The dream argument is the postulation that the act of dreaming provides preliminary evidence that the senses we trust to distinguish reality from illusion should not be fully trusted, and therefore, any state that is dependent on our senses should at the very least be carefully examined and rigorously tested to determine whether it is in fact reality.

Egocentric predicament

Egocentric predicament, a term coined by Ralph Barton Perry in an article (Journal of Philosophy 1910), is the problem of not being able to view reality outside of our own perceptions. All worldly knowledge takes the form of mental representations that our mind examines in different ways. Direct contact with reality cannot be made outside of our own minds; therefore, we cannot be sure reality even exists. This means that we are each limited to our own perceptual world and views. Solipsism is an extension of this which assumes that only one's own mind is sure to exist.

Since 1710, when George Berkeley broached in his fashion the problem of the egocentric predicament, denying the existence of material substance except as ideas in the minds of perceivers, and thus asserting a problematical relation with reality, hence has this thesis proved a stumbling block.

Samuel Johnson is well known for his "refutation" of Bishop Berkeley's immaterialism, his claim that matter did not actually exist but only seemed to exist: during a conversation with Boswell, Johnson powerfully stomped a nearby stone and proclaimed of Berkeley's theory, "I refute it thus!"Both Perry's concept and the term he used influenced American philosopher, Everett W. Hall to create the solecism "the categorio-centric predicament" to express the impossibility of seeing the world outside the "categories" imposed by one's native language and conceptual scheme.

First principle

A first principle is a basic, foundational, self-evident proposition or assumption that cannot be deduced from any other proposition or assumption. In philosophy, first principles are taught by Aristotelians, and nuanced versions of first principles are referred to as postulates by Kantians. In mathematics, first principles are referred to as axioms or postulates. In physics and other sciences, theoretical work is said to be from first principles, or ab initio, if it starts directly at the level of established science and does not make assumptions such as empirical model and parameter fitting.

Index of modern philosophy articles

This is a list of articles in modern philosophy.

1649 in philosophy

1658 in philosophy

17th century philosophy

A Few Words on Non-Intervention

A General View of Positivism

A Letter Concerning Toleration

A Philosophical Enquiry into the Origin of Our Ideas of the Sublime and Beautiful

A System of Logic

A Treatise Concerning the Principles of Human Knowledge

A Vindication of Natural Society

Adam Müller

Adam Smith

Adam Weishaupt

Age of Enlightenment

Alexander Gottlieb Baumgarten

Alexander Pfänder

Aloys Hirt

American Enlightenment

An Enquiry Concerning the Principles of Morals


Anarchism and anarcho-capitalism

Anarchism in Korea

Anarchism in Russia

Anarchism in Spain

Anarchism in Sweden

Anarchism in the United States

Anarchism in Turkey

Anarchism in Ukraine

Anarchism in Vietnam

Anarchism: A Documentary History of Libertarian Ideas

Anarchist Manifesto


Anioł Dowgird

Answering the Question: What Is Enlightenment?

Anthony Ashley-Cooper, 3rd Earl of Shaftesbury


Antoine Arnauld

Anton Kržan

Arnold Geulincx

Arnold Toynbee

Art manifesto

Arthur Schopenhauer

Arthur Schopenhauer's aesthetics

Auberon Herbert

Auguste Comte

Augustus De Morgan



Benjamin Constant

Bernard Bolzano

Bête machine

Beyond Good and Evil

Black Panther Party

Blaise Pascal

Borden Parker Bowne


Bronisław Trentowski

Cartesian doubt

Charles Batteux

Charles de Secondat, baron de Montesquieu

Charles Fourier

Charles Graves (bishop)

Charles Sanders Peirce


Christian Discourses

Christoph von Sigwart

Class consciousness

Classical Realism



Commodity fetishism


Concluding Unscientific Postscript to Philosophical Fragments

Cornelis Willem Opzoomer

Criticisms of electoralism

Critique of Judgement

Critique of Practical Reason

Critique of Pure Reason

Cultural hegemony

Dai Zhen

Daniel-Henry Kahnweiler

David Hume

David Ricardo

David Strauss

Dharmarāja Adhvarin


Dialectical materialism

Die Anarchisten

Direct action

Disquisitions relating to Matter and Spirit

Edifying Discourses in Diverse Spirits

Edward Abramowski

Edward Dembowski

Egoist anarchism


Émile Pouget

Ernst Mach

Ernst Schröder

Fear and Trembling

Feliks Jaroński

For Self-Examination

Francesco Saverio Merlino

Francis Bacon

Francis Hutcheson (philosopher)

Franciszek Krupiński

Friedrich Daniel Ernst Schleiermacher

Friedrich Engels

Friedrich Groos

Friedrich Nietzsche

Friedrich Schiller

Friedrich Theodor Vischer

Friedrich Wilhelm Joseph Schelling

General will

Geohumoral theory

Georg Friedrich Meier

Georg Wilhelm Friedrich Hegel

George Berkeley

George Boole

Giorgio Vasari

Gottfried Leibniz

Gotthold Ephraim Lessing

Groundwork of the Metaphysic of Morals

Hannah Arendt

Harriet Taylor Mill

Hayashi Hōkō

Hayashi Razan

Hayashi Ryūkō


Heimin Shimbun

Henri Bergson

Henry David Thoreau

Henry Home, Lord Kames

Herbert Spencer

Hirata Atsutane

Historical materialism

Hosoi Heishu

Hoter ben Shlomo

Howard Williams (humanitarian)

Hugo Grotius

Idea for a Universal History with a Cosmopolitan Purpose

Immanuel Kant

Individualist anarchism

Isaak Iselin

Itō Jinsai

Jakob Friedrich Fries

James Guillaume

Jan Wacław Machajski

Jean-Jacques Rousseau

Jean le Rond d'Alembert

Jena romantics

Jens Kraft

Jeremy Bentham

Jewish Communist Labour Party (Poalei Zion)

Jewish Communist Party (Poalei Zion)

Jewish Communist Union (Poalei Zion)

Johann Christian Lossius

Johann Friedrich Flatt

Johann Gottlieb Fichte

Johann Heinrich Lambert

Johann Joachim Lange

Johann Wolfgang von Goethe

Johannes Bredenburg

Johannes Phocylides Holwarda

John Austin (legal philosopher)

John Calvin

John Dewey

John Locke

John Stuart Mill

Józef Gołuchowski

Judah Leon Abravanel

Judge for Yourselves!

Justice as Fairness: A Restatement

Kaibara Ekken

Karl Heinrich Heydenreich

Karl Marx

Karl Wilhelm Friedrich Schlegel

Karl Wilhelm Ramler

Kitaro Nishida

Krastyo Krastev

Krystyn Lach Szyrma

Lazarus Geiger

Lectures on Aesthetics

Léon Dumont

Letters to a Philosophical Unbeliever

Lettre sur les aveugles à l'usage de ceux qui voient

Levi Hedge

Leviathan (book)

Lex, Rex

Libertarian Marxism

Libertarian socialism

List of communist ideologies

Ludwig Andreas Feuerbach

Ludwig Tieck

Luo Rufang

Man a Machine

Martin Luther

Marx's theory of alienation

Marx's theory of human nature

Marxist feminism

Marxist humanism

Marxist philosophy

Mary Wollstonecraft

Max Weber

Meditations on First Philosophy

Meinong's jungle

Memoirs Illustrating the History of Jacobinism

Metaphysical Foundations of Natural Science

Metaphysics of Morals

Methodios Anthrakites

Michael Gottlieb Birckner

Michael Hissmann

Michał Wiszniewski

Michel Henry

Mikhail Bakunin

Miura Baien

Modern philosophy

Moses Mendelssohn

Motoori Norinaga

Muhammad Iqbal

Mulla Sadra

Muro Kyūsō

New England Transcendentalists

Nicholas Leonicus Thomaeus

Nicolas Malebranche

Nicolaus Hieronymus Gundling

Nietzsche's views on women

Nietzsche and Philosophy

Nikolai Putyatin



Novum Organum

Observations on Man

Observations on the Feeling of the Beautiful and Sublime

Ogyū Sorai

On Liberty

On the Concept of Irony with Continual Reference to Socrates

On the Genealogy of Morality

Oration on the Dignity of Man

Outline of anarchism

Paul Rée

Philosophical Fragments

Philosophical Inquiries into the Essence of Human Freedom

Philosophy of Max Stirner

Philosophy of Spinoza

Pierre-Joseph Proudhon

Pierre Cally

Pierre Gassendi

Pierre Nicole

Poale Zion

Political Justice

Political philosophy of Immanuel Kant

Port-Royal Logic

Practice in Christianity


Prolegomena to Any Future Metaphysics


Property is theft!

Randall Swingler

Rate of exploitation

Reification (Marxism)

Relations of production

Relationship between Friedrich Nietzsche and Max Stirner

René Descartes

Repetition (Kierkegaard)

Revolutionary Left (disambiguation)

Richard Sault

Robert Leslie Ellis

Roger Fry

Rudolf Seydel

Rudolph Goclenius

Samuel Taylor Coleridge

Schopenhauer's criticism of the proofs of the parallel postulate

Science of Logic

Scottish School of Common Sense

Sebastian Petrycy

Seo Gyeong-deok

Simion Bărnuțiu

Sir William Hamilton, 9th Baronet

Social ecology


Søren Kierkegaard

Spinoza: Practical Philosophy

Stages on Life's Way

Statism and Anarchy

Stoicorum Veterum Fragmenta

Structural Marxism

Sturm und Drang

Suzuki Shōsan

Tan Sitong

The Art of Being Right

The Blood of Others

The Book on Adler

The Communist Manifesto

The Concept of Anxiety

The Crisis and a Crisis in the Life of an Actress

The Doctrine of Philosophical Necessity Illustrated

The False Subtlety of the Four Syllogistic Figures

The Foundations of Arithmetic

The Law of Peoples

The Methods of Ethics

The Only Possible Argument in Support of a Demonstration of the Existence of God

The Phenomenology of Spirit

The Point of View of My Work as an Author

The Sickness Unto Death

The Soul of Man under Socialism

The Subjection of Women

Thomas Carlyle

Thomas Hobbes

Thomas Jefferson

Thomas Paine

Thomas Robert Malthus

Thoughts on the True Estimation of Living Forces

Three Critics of the Enlightenment

Toju Nakae


Universal Natural History and Theory of Heaven

Utilitarianism (book)

Vasily Jakovlevich Zinger

Victor d'Hupay


Walter Goodnow Everett

War of Anti-Christ with the Church and Christian Civilization

What Is Property?

Wilhelm Heinrich Wackenroder

Wilhelm Windelband

Wilhelm Wundt

William Blackstone

William Godwin

William Graham Sumner

William Manderstown

William Whewell

Works of Love

Writing Sampler

Yamaga Sokō

Yamazaki Ansai

Yi I

James Burr

James Burr is an English writer of dark, although often humorous, paranoiac fiction. His first collection of short stories, "Ugly Stories For Beautiful People" was published in 2007 and was favourably compared to the work of Russell Hoban, David Cronenberg, early Kurt Vonnegut. and Philip K. Dick. The collection featured "Foetal Attractions" which won second prize in the "Roadworks 2000 Short Story Competition" and two of the stories in the collection, "It" and "Blue" later garnered honorable mentions in that year's "The Year’s Best Fantasy and Horror". HellNotes described the collection as "Odd, unique, very cool, and extremely readable" while Horror World described Burr as "not merely a “new” voice, he is a fresh voice – a different and disturbing voice - and one deserving of your attention.". His work has often been described as Bizarro fiction although he has no direct links to the group of writers working under that banner.

His work echoes that of early J.G.Ballard with its fascination with the mundane grittiness of the concrete underpass or the wet tarmac street, but it also has similarities with the surreal satirical works of Will Self, and the reality-questioning works of Cartesian doubt for which Philip K. Dick was so well known. Indeed, Burr is a well-known admirer of Dick's work having written a piece about him for The Guardian newspaper in 1995.

In an interview with "The Short Review" he stated that he was currently working on his first novel and "a collection of two novellas and a short story - all criticising certain aspects of contemporary life in Britain." He recently had flash fiction shortlisted for the 2017 Worcestershire Litfest and Fringe Flash Fiction competition.

La Cité antique

The Ancient City (La Cité antique), published in 1864, is the most famous book of the French historian Numa Denis Fustel de Coulanges (1830-1889). Taking inspiration from René Descartes, and based on texts of ancient historians and poets, the author investigates the origins of the most archaic institutions of Greek and Roman society.

In the preface of the book, he warns of the error that lies in examining the habits of ancient people with reference to those of today, when it is necessary to avoid our biases and study ancient peoples in the light of the facts.

Fustel de Coulanges sees religion and cult as the foundation of the institutions of the Greeks and Romans. Each family had their belief, their gods, and their worship. The rules of ownership, inheritance, etc., were governed by that cult. Over time, need has led men to regularize and make more consistent their relations with one another, and the rules that govern the family were transferred to increasingly larger units, arriving eventually at the city. Therefore, the origin of the city is also religious, as is witnessed by the practice of lustration, a periodic purification ceremony in connection with the census of all citizens, and by the public banquets in honor of local gods.

The laws originally encoded the privileges of the aristocracy, causing great discomfort to the plebs and a social revolution in which the common well-being of society became the new basis of religion. The city thus came into being for some time, until its extinction with the arrival of Christianity.

Metaphysics (album)

Metaphysics is the second album by Duncan Avoid.

Philosophy in Canada

The study and teaching of philosophy in Canada date from the time of New France. There has since developed no particular "Canadian" school of philosophy. Rather, Canadian philosophers have reflected particular views of established European and later American schools of philosophical thought, be it Thomism, Objective Idealism, or Scottish Common Sense Realism. Since the mid-twentieth century the depth and scope of philosophical activity in Canada has increased dramatically. This article focuses on the evolution of epistemology, logic, the philosophy of mind, metaphysics, ethics and metaethics, and continental philosophy in Canada.

René Descartes

René Descartes (UK: ; US: ; French: [ʁəne dekaʁt]; Latinized: Renatus Cartesius; adjectival form: Cartesian (); 31 March 1596 – 11 February 1650) was a French philosopher, mathematician, and scientist. A native of the Kingdom of France, he spent about 20 years (1629–1649) of his life in the Dutch Republic after serving for a while in the Dutch States Army of Maurice of Nassau, Prince of Orange and the Stadtholder of the United Provinces. One of the most notable intellectual figures of the Dutch Golden Age, Descartes is also widely regarded as one of the founders of modern philosophy.

Many elements of Descartes' philosophy have precedents in late Aristotelianism, the revived Stoicism of the 16th century, or in earlier philosophers like Augustine. In his natural philosophy, he differed from the schools on two major points: first, he rejected the splitting of corporeal substance into matter and form; second, he rejected any appeal to final ends, divine or natural, in explaining natural phenomena. In his theology, he insists on the absolute freedom of God's act of creation.

Refusing to accept the authority of previous philosophers, Descartes frequently set his views apart from those of his predecessors. In the opening section of the Passions of the Soul, an early modern treatise on emotions, Descartes goes so far as to assert that he will write on this topic "as if no one had written on these matters before". His best known philosophical statement is "I think, therefore I am" (French: Je pense, donc je suis; Latin: Ego cogito, ergo sum), found in Discourse on the Method (1637; written in French and Latin) and Principles of Philosophy (1644; written in Latin).Descartes laid the foundation for 17th-century continental rationalism, later advocated by Spinoza and Leibniz, and was later opposed by the empiricist school of thought consisting of Hobbes, Locke, Berkeley, and Hume. Leibniz, Spinoza, and Descartes were all well-versed in mathematics as well as philosophy, and Descartes and Leibniz contributed greatly to science as well.

Descartes' Meditations on First Philosophy (1641) continues to be a standard text at most university philosophy departments. Descartes' influence in mathematics is equally apparent; the Cartesian coordinate system was named after him. He is credited as the father of analytical geometry, the bridge between algebra and geometry—used in the discovery of infinitesimal calculus and analysis. Descartes was also one of the key figures in the Scientific Revolution.

Suspension of judgment

Suspended judgment is a cognitive process and a rational state of mind in which one withholds judgments, particularly on the drawing of moral or ethical conclusions. The opposite of suspension of judgment is premature judgment, usually shortened to prejudice, or in some philosophical systems such as Pyrrhonism the opposite is dogma. While prejudgment involves drawing a conclusion or making a judgment before having the information relevant to such a judgment, suspension of judgment involves waiting for all the facts before making a decision.

Skeptical hypotheses


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