Tabula rasa
Encyclopedia
Tabula rasa is the epistemological theory that individuals are born without built-in mental content and that their knowledge comes from experience
Experience
Experience as a general concept comprises knowledge of or skill in or observation of some thing or some event gained through involvement in or exposure to that thing or event....

 and perception
Perception
Perception is the process of attaining awareness or understanding of the environment by organizing and interpreting sensory information. All perception involves signals in the nervous system, which in turn result from physical stimulation of the sense organs...

. Generally proponents of the tabula rasa thesis favour the "nurture" side of the nature versus nurture
Nature versus nurture
The nature versus nurture debate concerns the relative importance of an individual's innate qualities versus personal experiences The nature versus nurture debate concerns the relative importance of an individual's innate qualities ("nature," i.e. nativism, or innatism) versus personal experiences...

 debate, when it comes to aspects of one's personality, social and emotional behaviour, and intelligence. The term in Latin equates to the English "blank slate" (or more accurately, "erased slate") (which refers to writing on a slate sheet
Slate (writing)
A writing slate is a piece of flat material used as a medium for writing.In the 19th century, writing slates were made of slate, which is more durable than paper and was cheap at the time when paper was expensive. It was used to allow children to practice writing...

 in chalk) but comes from the Roman tabula or wax tablet
Wax tablet
A wax tablet is a tablet made of wood and covered with a layer of wax, often linked loosely to a cover tablet, as a "double-leaved" diptych. It was used as a reusable and portable writing surface in Antiquity and throughout the Middle Ages...

, used for notes, which was blanked by heating the wax and then smoothing it to give a tabula rasa.

History

In Western philosophy
Western philosophy
Western philosophy is the philosophical thought and work of the Western or Occidental world, as distinct from Eastern or Oriental philosophies and the varieties of indigenous philosophies....

, traces of the idea that came to be called the tabula rasa appear as early as the writings of Aristotle
Aristotle
Aristotle was a Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. His writings cover many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, linguistics, politics, government, ethics, biology, and zoology...

. Aristotle writes of the unscribed tablet in what is probably the first textbook of psychology
Psychology
Psychology is the study of the mind and behavior. Its immediate goal is to understand individuals and groups by both establishing general principles and researching specific cases. For many, the ultimate goal of psychology is to benefit society...

 in the Western canon
Western canon
The term Western canon denotes a canon of books and, more broadly, music and art that have been the most important and influential in shaping Western culture. As such, it includes the "greatest works of artistic merit." Such a canon is important to the theory of educational perennialism and the...

, his treatise "Περί Ψυχῆς" (De Anima or On the Soul, Book III, chapter 4). However, besides some arguments by the Stoics and Peripatetics, the notion of the mind as a blank slate went largely unnoticed for more than 1,000 years.

In the 11th century, the theory of tabula rasa was developed more clearly by the Islamic philosopher, Ibn Sina
Avicenna
Abū ʿAlī al-Ḥusayn ibn ʿAbd Allāh ibn Sīnā , commonly known as Ibn Sīnā or by his Latinized name Avicenna, was a Persian polymath, who wrote almost 450 treatises on a wide range of subjects, of which around 240 have survived...

 (known as "Avicenna" in the Western world
Western world
The Western world, also known as the West and the Occident , is a term referring to the countries of Western Europe , the countries of the Americas, as well all countries of Northern and Central Europe, Australia and New Zealand...

). He argued that the "human intellect at birth is rather like a tabula rasa, a pure potentiality that is actualized through education and comes to know" and that knowledge is attained through "empirical
Empirical
The word empirical denotes information gained by means of observation or experimentation. Empirical data are data produced by an experiment or observation....

 familiarity with objects in this world from which one abstracts universal concepts" which is developed through a "syllogistic
Syllogism
A syllogism is a kind of logical argument in which one proposition is inferred from two or more others of a certain form...

 method of reasoning; observations lead to prepositional statements, which when compounded lead to further abstract concepts." He further argued that the intellect itself "possesses levels of development from the material intellect (al-‘aql al-hayulani), that potentiality can acquire knowledge to the active intellect (al-‘aql al-fa‘il), the state of the human intellect at conjunction with the perfect source of knowledge."

In the 12th century, the Andalusian
Al-Andalus
Al-Andalus was the Arabic name given to a nation and territorial region also commonly referred to as Moorish Iberia. The name describes parts of the Iberian Peninsula and Septimania governed by Muslims , at various times in the period between 711 and 1492, although the territorial boundaries...

-Islamic philosopher
Early Islamic philosophy
Early Islamic philosophy or classical Islamic philosophy is a period of intense philosophical development beginning in the 2nd century AH of the Islamic calendar and lasting until the 6th century AH...

 and novelist Ibn Tufail
Ibn Tufail
Ibn Tufail was an Andalusian Muslim polymath: an Arabic writer, novelist, Islamic philosopher, Islamic theologian, physician, vizier,...

 (known as "Abubacer" or "Ebn Tophail" in the West) demonstrated the theory of tabula rasa as a thought experiment
Thought experiment
A thought experiment or Gedankenexperiment considers some hypothesis, theory, or principle for the purpose of thinking through its consequences...

 through his Arabic philosophical novel
Arabic literature
Arabic literature is the writing produced, both prose and poetry, by writers in the Arabic language. The Arabic word used for literature is adab which is derived from a meaning of etiquette, and implies politeness, culture and enrichment....

, Hayy ibn Yaqzan, in which he depicted the development of the mind of a feral child
Feral child
A feral child is a human child who has lived isolated from human contact from a very young age, and has no experience of human care, loving or social behavior, and, crucially, of human language...

 "from a tabula rasa to that of an adult, in complete isolation from society" on a desert island
Desert island
A desert island or uninhabited island is an island that has yet to be populated by humans. Uninhabited islands are often used in movies or stories about shipwrecked people, and are also used as stereotypes for the idea of "paradise". Some uninhabited islands are protected as nature reserves and...

, through experience
Experience
Experience as a general concept comprises knowledge of or skill in or observation of some thing or some event gained through involvement in or exposure to that thing or event....

 alone. The Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 translation of his philosophical novel
Philosophical novel
Philosophical fiction refers to works of fiction in which a significant proportion of the work is devoted to a discussion of the sort of questions normally addressed in discursive philosophy. These might include the function and role of society, the purpose of life, ethics or morals, the role of...

, entitled Philosophus Autodidactus, published by Edward Pococke
Edward Pococke
Edward Pococke was an English Orientalist and biblical scholar.-Early life:He was the son of clergyman from Chieveley in Berkshire, and was educated at Lord Williams's School of Thame in Oxfordshire and at Corpus Christi College, Oxford...

 the Younger in 1671, had an influence on John Locke
John Locke
John Locke FRS , widely known as the Father of Liberalism, was an English philosopher and physician regarded as one of the most influential of Enlightenment thinkers. Considered one of the first of the British empiricists, following the tradition of Francis Bacon, he is equally important to social...

's formulation of tabula rasa in An Essay Concerning Human Understanding
An Essay Concerning Human Understanding
First appearing in 1690 with the printed title An Essay Concerning Humane Understanding, An Essay Concerning Human Understanding by John Locke concerns the foundation of human knowledge and understanding. He describes the mind at birth as a blank slate filled later through experience...

.

In the 13th century, St. Thomas Aquinas brought the Aristotelian
Aristotelianism
Aristotelianism is a tradition of philosophy that takes its defining inspiration from the work of Aristotle. The works of Aristotle were initially defended by the members of the Peripatetic school, and, later on, by the Neoplatonists, who produced many commentaries on Aristotle's writings...

 and Avicennian notions to the forefront of Christian thought
Christian philosophy
Christian philosophy may refer to any development in philosophy that is characterised by coming from a Christian tradition.- Origins of Christian philosophy :...

. These notions sharply contrasted with the previously held Platonic
Platonism
Platonism is the philosophy of Plato or the name of other philosophical systems considered closely derived from it. In a narrower sense the term might indicate the doctrine of Platonic realism...

 notions of the human mind as an entity that preexisted somewhere in the heavens, before being sent down to join a body here on Earth (see Plato's Phaedo
Phaedo
Plato's Phaedo is one of the great dialogues of his middle period, along with the Republic and the Symposium. The Phaedo, which depicts the death of Socrates, is also Plato's seventh and last dialogue to detail the philosopher's final days .In the dialogue, Socrates...

and Apology, as well as others). St. Bonaventure (also 13th century) was one of Aquinas' fiercest intellectual opponents, offering some of the strongest arguments towards the Platonic idea of the mind.
The writings of Avicenna, Ibn Tufail and Aquinas on the tabula rasa theory stood unprogressed for several centuries. In fact, our modern idea of the theory is mostly attributed to John Locke
John Locke
John Locke FRS , widely known as the Father of Liberalism, was an English philosopher and physician regarded as one of the most influential of Enlightenment thinkers. Considered one of the first of the British empiricists, following the tradition of Francis Bacon, he is equally important to social...

's expression of the idea in An Essay Concerning Human Understanding
An Essay Concerning Human Understanding
First appearing in 1690 with the printed title An Essay Concerning Humane Understanding, An Essay Concerning Human Understanding by John Locke concerns the foundation of human knowledge and understanding. He describes the mind at birth as a blank slate filled later through experience...

in the 17th century. In Locke's philosophy, tabula rasa was the theory that the (human) mind is at birth a "blank slate" without rules for processing data, and that data is added and rules for processing are formed solely by one's sensory
Sense
Senses are physiological capacities of organisms that provide inputs for perception. The senses and their operation, classification, and theory are overlapping topics studied by a variety of fields, most notably neuroscience, cognitive psychology , and philosophy of perception...

 experiences. The notion is central to Lockean empiricism
Empiricism
Empiricism is a theory of knowledge that asserts that knowledge comes only or primarily via sensory experience. One of several views of epistemology, the study of human knowledge, along with rationalism, idealism and historicism, empiricism emphasizes the role of experience and evidence,...

. As understood by Locke, tabula rasa meant that the mind of the individual was born "blank", and it also emphasized the individual's freedom to author his or her own soul. Each individual was free to define the content of his or her character - but his or her basic identity as a member of the human species cannot be so altered. It is from this presumption of a free, self-authored mind
Mind
The concept of mind is understood in many different ways by many different traditions, ranging from panpsychism and animism to traditional and organized religious views, as well as secular and materialist philosophies. Most agree that minds are constituted by conscious experience and intelligent...

 combined with an immutable human nature that the Lockean doctrine of "natural" rights derives. Locke's idea of tabula rasa is frequently compared with Thomas Hobbes
Thomas Hobbes
Thomas Hobbes of Malmesbury , in some older texts Thomas Hobbs of Malmsbury, was an English philosopher, best known today for his work on political philosophy...

's viewpoint of human nature, in which humans are endowed with inherent mental content – particular with selfishness.

Tabula Rasa is also featured in Sigmund Freud's
Sigmund Freud
Sigmund Freud , born Sigismund Schlomo Freud , was an Austrian neurologist who founded the discipline of psychoanalysis...

 psychoanalysis
Psychoanalysis
Psychoanalysis is a psychological theory developed in the late 19th and early 20th centuries by Austrian neurologist Sigmund Freud. Psychoanalysis has expanded, been criticized and developed in different directions, mostly by some of Freud's former students, such as Alfred Adler and Carl Gustav...

. Freud depicted personality traits as being formed by family dynamics (see Oedipus complex
Oedipus complex
In psychoanalytic theory, the term Oedipus complex denotes the emotions and ideas that the mind keeps in the unconscious, via dynamic repression, that concentrate upon a boy’s desire to sexually possess his mother, and kill his father...

, etc.). Freud's theories imply that humans lack free will, but also that genetic influences on human personality are minimal. In psychoanalysis, one is largely determined by one's upbringing.

The tabula rasa concept became popular in social sciences in the 20th century. Eugenics
Eugenics
Eugenics is the "applied science or the bio-social movement which advocates the use of practices aimed at improving the genetic composition of a population", usually referring to human populations. The origins of the concept of eugenics began with certain interpretations of Mendelian inheritance,...

 (mainstream in the late 19th and early 20th centuries) came to be seen not as a sound policy but as a crime. The idea that genes (or simply "blood") determined character took on racist overtones. By the 1970s, some scientists had come to see gender identity as socially constructed rather than rooted in genetics (see John Money
John Money
John William Money was a psychologist, sexologist and author, specializing in research into sexual identity and biology of gender...

), a concept still current (see Anne Fausto-Sterling
Anne Fausto-Sterling
Anne Fausto-Sterling, Ph. D. is Professor of Biology and Gender Studies at Brown University. She participates actively in the field of sexology and has written extensively on the fields of biology of gender, sexual identity, gender identity, and gender roles.-Life and career:Fausto-Sterling...

), although strongly contested.
This swing of the pendulum accompanied suspicion of innate differences in general (see racism
Racism
Racism is the belief that inherent different traits in human racial groups justify discrimination. In the modern English language, the term "racism" is used predominantly as a pejorative epithet. It is applied especially to the practice or advocacy of racial discrimination of a pernicious nature...

) and a propensity to "manage" society, where the real power must be if people are born blank.

Literature

William Golding
William Golding
Sir William Gerald Golding was a British novelist, poet, playwright and Nobel Prize for Literature laureate, best known for his novel Lord of the Flies...

's novel the Lord of the Flies
Lord of the Flies
Lord of the Flies is a novel by Nobel Prize-winning author William Golding about a group of British boys stuck on a deserted island who try to govern themselves, with disastrous results...

is a narrative unfolding of the human mind as more in tune with the views of Kant
KANT
KANT is a computer algebra system for mathematicians interested in algebraic number theory, performing sophisticated computations in algebraic number fields, in global function fields, and in local fields. KASH is the associated command line interface...

: full of innate cognitive and moral devices. Golding wrote the book in hope of convincing his readers that humans are born with an innate evil, and it is the job of humans to contain that evil. At least two of his protagonists had the capacity to resist the call to evil. Whether this represented a residual of socialisation, and they would have eventually turned, or if they contained a biological factor of amity is unresolved.

Biogeography

In biogeography, particularly phytogeography
Phytogeography
Phytogeography , also called geobotany, is the branch of biogeography that is concerned with the geographic distribution of plant species...

, the tabula rasa hypothesis about the origin of a biota
Biota (ecology)
Biota are the total collection of organisms of a geographic region or a time period, from local geographic scales and instantaneous temporal scales all the way up to whole-planet and whole-timescale spatiotemporal scales. The biota of the Earth lives in the biosphere.-See...

 in formerly glaciated areas refers to the idea that all species have immigrated into completely denuded land after the retreat of glaciers. It may also refer to the area around the Arctic caps in which glacial melting has exposed the area to flood wiping everything away.

Computer science

In computer science
Computer science
Computer science or computing science is the study of the theoretical foundations of information and computation and of practical techniques for their implementation and application in computer systems...

, tabula rasa refers to the development of autonomous agents which are provided with a mechanism to reason and plan toward their goal, but no "built-in" knowledge-base of their environment. They are thus truly a "blank slate".

In reality autonomous agents are provided with an initial data-set or knowledge-base, but this should not be immutable or it will hamper autonomy and heuristic ability. Even if the data-set is empty, it can usually be argued that there is an in-built bias
Bias
Bias is an inclination to present or hold a partial perspective at the expense of alternatives. Bias can come in many forms.-In judgement and decision making:...

 in the reasoning and planning mechanisms. Either intentionally or unintentionally placed there by the human designer, it thus negates the true spirit of tabula rasa.

Psychology and neurobiology

As in Philosophy, there has been an enduring claim that in psychology and neurobiology that the brain is tabula rasa, at least with respect to its behavioural repertoire. Thus several psychologists such as Howe
Michael Howe (psychologist)
There are other people called Michael Howe ----Michael Howe was a British cognitive psychologist. He took BSc and PhD degrees at the University of Sheffield and worked at North American universities before taking a post as lecturer at the University of Exeter in England, where he worked for the...

 have argued against the existence of innate talent, while in neuroscience there have been debates that the brain functions with Mass action
Mass action
In Chemistry, the law of mass action is a mathematical model that explains and predicts behaviors of solutions in dynamic equilibrium. It can be described with two aspects: 1) the equilibrium aspect, concerning the composition of a reaction mixture at equilibrium and 2) the kinetic aspect...

, rather than by a series of interacting mechanisms – for instance by Karl Lashley
Karl Lashley
-External links:*...

 and others.

Scientists recognize that the entire cerebral cortex
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...

 is indeed preprogrammed and organized in order to process sensory input, motor control, emotions, and natural responses. These programmed mechanisms in the brain then act to learn and refine the ability of the organism.
For example, Steven Pinker
Steven Pinker
Steven Arthur Pinker is a Canadian-American experimental psychologist, cognitive scientist, linguist and popular science author...

 argues that while the brain is "programmed" to pick up spoken language easily, it is not programmed to learn to read and write, and a human generally will not spontaneously learn to do so.

Important evidence against the tabula rasa model of the mind comes from Behavioural genetics
Behavioural genetics
Quantitative human behavioural genetics is a specialisation in the biological field of behaviour genetics that studies the role of genetics in human behaviour employing quantitative-genetic methods. The field is an overlap of quantitative genetics and psychology...

, especially twin and adoption
Adoption
Adoption is a process whereby a person assumes the parenting for another and, in so doing, permanently transfers all rights and responsibilities from the original parent or parents...

 studies. These indicate strong genetic influences on personal characteristics such as IQ, alcoholism
Alcoholism
Alcoholism is a broad term for problems with alcohol, and is generally used to mean compulsive and uncontrolled consumption of alcoholic beverages, usually to the detriment of the drinker's health, personal relationships, and social standing...

, gender identity
Gender identity
A gender identity is the way in which an individual self-identifies with a gender category, for example, as being either a man or a woman, or in some cases being neither, which can be distinct from biological sex. Basic gender identity is usually formed by age three and is extremely difficult to...

, and other traits. Critically, multivariate studies show that the distinct faculties of the mind such as memory and reason fractionate along genetic boundaries. Cultural universals such as emotion
Emotion
Emotion is a complex psychophysiological experience of an individual's state of mind as interacting with biochemical and environmental influences. In humans, emotion fundamentally involves "physiological arousal, expressive behaviors, and conscious experience." Emotion is associated with mood,...

 and the relative resilience of psychological adaptation to accidental biological changes (for instance the David Reimer
David Reimer
David Reimer was a Canadian man who was born as a healthy male, but was sexually reassigned and raised as female after his penis was accidentally destroyed during circumcision. Psychologist John Money oversaw the case and reported the reassignment as successful, and as evidence that gender...

 case of gender reassignment following an accident) also support basic biological mechanisms in the mind.

Politics

As with evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...

, the notion of the human mind as "blank slate" is attractive (or repulsive) to some individuals, and therefore tends to correlate with political views. On the one hand, the theory of a "blank slate" is attractive to some since it implies that innate
Nature (innate)
Nature is innate behavior , character or essence, especially of a human. This is a way of using the word nature which goes back to its earliest forms in Greek...

 mental differences cannot exist, thus making racism
Racism
Racism is the belief that inherent different traits in human racial groups justify discrimination. In the modern English language, the term "racism" is used predominantly as a pejorative epithet. It is applied especially to the practice or advocacy of racial discrimination of a pernicious nature...

 and sexism
Sexism
Sexism, also known as gender discrimination or sex discrimination, is the application of the belief or attitude that there are characteristics implicit to one's gender that indirectly affect one's abilities in unrelated areas...

 illogical. On the other hand, the theory also implies that there is no limit to the ways in which society can shape human psychology. The opposing view is that human nature is innate at birth and that differences arise from genetics. To conclude that the mind does or does not have component mechanisms based on such political or philosophical implications (rather than empirical evidence) would be a form of the Moralistic fallacy
Moralistic fallacy
The moralistic fallacy is in essence the reverse of the naturalistic fallacy.Naturalistic fallacy presumes that what is—or what occurs—forms what ought to be. Thus the observed natural is reasoned a priori as moral....

.

Architecture

In discussions of architecture since the 1950s, the term tabula rasa has been used in arguments against what were criticized as insensitive design strategies employed by a monolithic Modern Movement, brought to the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 from Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

 by émigrés like Walter Gropius
Walter Gropius
Walter Adolph Georg Gropius was a German architect and founder of the Bauhaus School who, along with Ludwig Mies van der Rohe and Le Corbusier, is widely regarded as one of the pioneering masters of modern architecture....

 and Mies van der Rohe. Entirely separated from its Aristotelian or Lockean meaning, the tabula rasa in architecture signifies the utopian blank slate on which a new building is conceived, free of compromise or complication after the demolition of what previously stood on the site. Le Corbusier
Le Corbusier
Charles-Édouard Jeanneret, better known as Le Corbusier , was a Swiss-born French architect, designer, urbanist, writer and painter, famous for being one of the pioneers of what now is called modern architecture. He was born in Switzerland and became a French citizen in 1930...

's Plan Voisin, which proposed the demolition of a large area of central Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

 and the construction of a new city with vast open spaces and tall towers, provides a good example of what was associated with the term tabula rasa in the architectural discourse.

See also

Related topics
  • Empiricism
    Empiricism
    Empiricism is a theory of knowledge that asserts that knowledge comes only or primarily via sensory experience. One of several views of epistemology, the study of human knowledge, along with rationalism, idealism and historicism, empiricism emphasizes the role of experience and evidence,...

  • Fitra
    Fitra
    Fitra, or fitrah , is an Arabic word meaning ‘disposition’, ‘nature’, ‘constitution’, or ‘instinct’. In a mystical context, it can connote intuition or insight...

  • Human nature
    Human nature
    Human nature refers to the distinguishing characteristics, including ways of thinking, feeling and acting, that humans tend to have naturally....

  • Innatism
    Innatism
    Innatism is a philosophical doctrine that holds that the mind is born with ideas/knowledge, and that therefore the mind is not a 'blank slate' at birth, as early empiricists such as John Locke claimed...

  • Nature versus nurture
    Nature versus nurture
    The nature versus nurture debate concerns the relative importance of an individual's innate qualities versus personal experiences The nature versus nurture debate concerns the relative importance of an individual's innate qualities ("nature," i.e. nativism, or innatism) versus personal experiences...

  • Nirvana
    Nirvana
    Nirvāṇa ; ) is a central concept in Indian religions. In sramanic thought, it is the state of being free from suffering. In Hindu philosophy, it is the union with the Supreme being through moksha...

  • Psychological nativism
    Psychological nativism
    In the field of psychology, nativism is the view that certain skills or abilities are 'native' or hard wired into the brain at birth. This is in contrast to empiricism, the 'blank slate' or tabula rasa view, which states that the brain has inborn capabilities for learning from the environment but...

  • Rationalism
    Rationalism
    In epistemology and in its modern sense, rationalism is "any view appealing to reason as a source of knowledge or justification" . In more technical terms, it is a method or a theory "in which the criterion of the truth is not sensory but intellectual and deductive"...

  • Standard social science model
    Standard social science model
    The term the Standard Social Science Model was first introduced to a wide audience by John Tooby and Leda Cosmides in the 1992 edited volume The Adapted Mind, to describe the "blank slate," social constructionist,or "cultural determinist" perspective that they claim is the dominant theoretical...


Related works
  • The Blank Slate
    The Blank Slate
    The Blank Slate: The Modern Denial of Human Nature is a best-selling 2002 book by Steven Pinker arguing against tabula rasa models of the social sciences. Pinker argues that human behavior is substantially shaped by evolutionary psychological adaptations...

    • Steven Pinker
      Steven Pinker
      Steven Arthur Pinker is a Canadian-American experimental psychologist, cognitive scientist, linguist and popular science author...

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