Timeline


To begin exploring the timeline below, items can be clicked on to display the full text. Dragging the timeline to the left or right will pan through the range of years.

The and arrows can be used to navigate through each event consecutively. The or icons will zoom in or out, changing the range of years shown in the viewport.

BCE Timeline

600 BCE — 469 BCE

Cosmologists (Pre-Socratics)

First in recorded history to offer answers to questions about the natural world that will form the foundation of Western philosophy (epistemology and metaphysics) and science. Later Western philosophical positions (monism, pluralism, dualism, materialism, and rationalism) begin here.

510 BCE

Alcmaeon

First recorded observation that the brain is involved with sensory processes and that perception is mediated by pneuma (breath) contained within an animal or human body.

428 BCE — 347 BCE

Plato

Later philosophical positions of idealism, rationalism, and dualism can be seen in his thought (theory of forms). Ascribed mental properties to psyche/soul, and believed its physical location in the body was the brain.

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384 BCE — 322 BCE

Aristotle

His investigations of the physical world form the basis of empiricism. Establishes the Lyceum in 335 BCE, a place where he can engage with his students in cooperative research in natural history. Aristotle seated the psyche/soul in the heart. He can be considered the founder of psychology as a discipline: he is the first to consider the problem of the psyche/soul as an object of study separate from other human concerns.

350 BCE

De Anima "On the Soul"

Aristotle. Treatise that defines the nature and activities (biological and psychological) of the psyche/soul.

323 BCE — 31 BCE

Roman philosophy

Concerns with happiness, maximizing personal gain, escape from the ills of the world (Skepticism, Epicureanism), but also moral behavior and self-restraint, moderation (Stoicism). Emphasis on the conduct of man in the here and now (rather than viewing conduct as linked to consequences in an afterlife).

31 BCE

Roman Empire begins

Caesar Augustus becomes first emperor of Rome.

100 — 165

Almagest

Claudius Ptolemy. Geocentric model of the apparent motions of the stars and planetary paths. Profoundly influential scientific text, it was accepted for more than 1,200 years through the early Renaissance.

129 — 199

Galen

Develops the humor theory of temperament (first typology of personality). The theory of the four humors did not originate with Galen, however; it is an iteration of Hippocrates's adapation of Empedocles's elemental theory of the cosmos.

129 — 199

pneuma theory

Galen incorporated the ancient concept of pneuma into his physiological theories: pneuma (breath, air) mediated between the soul/psyche and bodily action. Pneuma theory was revised as the animal spirits doctrine, a physiological theory of functions such as volition, muscle contraction, cognition, and sensation. The animal spirits doctrine was entrenched in classical medical thought until the late 1700s when Luigi Galvani's experiments in 1791 displaced it.

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354 — 430

St. Augustine

Writes the Confessions of St. Augustine.

380

Christianity is official religion of Rome

Roman Empire officially adopts Christianity as its state religion.

476

Roman Empire (Western) ends

Roman Emperor Romulus Augustulus is replaced by Germanic King Odoacer. Invasions of the Roman Empire have hindered European education.

700 — 850

Carolingian Europe is a stable Europe

The rule of the Frankish king Charlemagne unites Western Europe under Christendom (literally a "realm of Christians") and a period of intellectual activity ensues. In monasteries and cathedrals, schools operate and commentaries and summaries of ancient texts appear.

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800 — 1500

Islamic Golden Age

Islamic civilization flourishes and cities such as Baghdad, Istanbul, and Cordoba become centers for culture and intellectual activity (e.g., "The House of Baghdad", 832 CE). Learned individuals in these cities engage in a massive translation of scientific works from ancient Greece, Rome, and Egypt (essentiallly preserving this ancient knowledge, as many of the ancient texts were destroyed during the fall of the Roman Empire). Individuals such as Rhazes, Avicenna (Canon of Medicine), Alhazen (Book of Optics), Al-Ghazali, and Averroës made original contributions to knowledge in several areas, among them ophthalmology, astronomy, mathematics, physiology, and surgery. Averroës writes The Incoherence of the Incoherence, and On the Harmony of Religions and Philosophy; his position that philosophy can inform religion (Islamic scripture) had a lasting influence among later Western philosophers.

800 — 1000

Western Europe destabilizes

Charlemagne's empire distintegrates: Magyars, Muslims, and Vikings attack Western Europe. New political entities form (kingdoms in England, automous domains in West Francia [France], a Holy Roman Empire in East Francia [Gemany], and strong cities in the Italian peninsula) that are the basis of the European nation-states with which we are familiar today.

1000 — 1300

Conditions ripe in Europe for intellectual activity

Beginning around 1100 CE, Western Europe enjoys a period of improved conditions: fewer invasions, strong rulers, and even better weather are said to account for economic stability and intellectual growth.

1095

First Crusades

Pope Urban II summons Christian warriors to reconquer the Holy Land (drive Muslims from Jerusalem).

1100

Enormous intellectual activity in Europe

Intellectual activity begins to peak. It takes many forms: original scientific works produced by Islamic authors, the collection and dissemination of original texts of the ancient Greeks, commentaries on the ancient Greek texts written by Islamic authors (translated from Greek to Arabic), and the translation of these works from Arabic into Latin.

1100 — 1400

European universities emerge

Universities emerge as guilds (not buildings) of male students who train in the liberal arts and a few specialized disciplines: medicine, law, philosophy, theology.

1158

Charter granted to University of Bologna (Italy)

First university; oldest in the world. Specialities: canon and civil law.

1200

Charter granted to University of Paris

Known as the Sorbonne; second-oldest unversity. Specialities: philosophy and theology.

1210

Aristotle banned

Teaching of Aristotle's works forbidden at the University of Paris; seen as a threat to Christian doctrine.

1215

Magna Carta signed

English barons force King John of England to sign a document that guarantees, among other things, tax collection only by legal means and no imprisonment without trial. It is a foundation of modern democracy and a source of later legal systems.

1225 — 1274

Thomas Aquinas and Scholasticism

Italian philosopher and theologian whose works influenced Roman Catholic theology and Western philosophy. His professional life epitomized that of philosophers in a medieval university: their goal was to reconcile questions concerning faith (scripture) with reason so that Christian church teachings had a logical foundation. Scholasticism is both a learning method and philosophical system that peaked with Aquinas's work. It is a method of reasoning applied to the problem of reconciling the philosophy of ancient Greece with Christian theology (e.g., the nature of human beings, the existence and attributes of God).

1231

Charter granted to University of Cambridge

English university

1248

Charter granted to University of Oxford

English university

1300 — 1625

Renaissance

Cultural events occurring on a large, widespread scale in Europe, beginning in Italy and spreading to the rest of the continent. Among its defining intellectual features: rediscovery of Greek classics, new interest in mathematics, expanding geographic knowledge, wider epistemology.

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1300 — 1625

Renaissance Humanism

Philosophical movement that reflects new interest in human affairs, manifested in art, music, literature, science. Generally speaking, a more human-centered, rather than religion-centered, perspective on life. Expressed in works of Francesco Petrarch, Niccolò Machiavelli, and Leonardo da Vinci.

1340

Black Plague

Italian ships bring rats carrying fleas infected with the Black Plague, which will kill 25 million people in Europe (one-third of the European population).

1400 — 1450

End of the medieval period

Defined by some historians as the fall of the Byzantine Empire; defined by others as the perfection of movable type by Johannes Gutenberg.

1403

Bethlem Hospital cares for mentally ill

London hospital that transitions to caring for people with mental illnesses. Informally known as "Bedlam".

1450 — 1524

First use (?) of term "psychology" to denote the science of mental life

Historical scholarship suggests that the first scholar to use the term "psychology" may have been Marko Marulić, a Croatian humanist. The term appears in the title Psichiologia de ratione animae humanae, in a list of his works (the actual work has not been found).

1453

Byzantine Empire (Eastern Roman) ends

Constantinople is conquered by Ottoman Muslims.

1487

The Malleus Maleficarium

Written by Heinrich Kramer and James Sprenger, "The Hammer of Witches" is a famous medieval treatise that instructs magistrates on how to identify, interrogate, and convict witches.

1492

Old World meets New World

Christopher Columbus makes first voyage to the Americas.

1517

Protestant Reformation begins

Martin Luther distributes his Disputation on the Power of Indulgences (also known as the Ninety-five Theses), which he wrote as a criticism of the Catholic Church's abuse of the practice of distributing indulgences (clergy receiving payment for granting indulgences).

1543

Start of Scientific (Copernican) Revolution

Profound transformation of thought, circa 1550 through 1700, about the physical world as ancient beliefs were replaced by modern science. Replaces the thinking of Aristotle, Ptolemy, and Galen of the Middle Ages. First occurs in mathematics, physics and astronomy, anatomy, and chemistry.

1543

On the Revolutions of the Celestial Spheres

Nicolas Copernicus. Often viewed as the start to the Scientific Revolution, it is a model of planetary motion based on the assumption that the Earth and other planets move around the Sun.

1543

On the Structure of the Human Body

Andreas Vesalius. A major advance in the history of anatomy, this collection of books was based on his dissections of corpses and features illustrations whose quality was far better than previous illustrations.

1583

University of Edinburgh

University established in Scotland that will earn Edinburgh a reputation as a major intellectual center during the Age of Enlightenment. One of the earliest universities founded without a Papal bull (charter issued from a Pope of the Roman Catholic Church).

1607

European settlement of the Americas

English establish a colony at Jamestown, Virginia.

1608

First telescope invented

Dutch scientist Hans Lippershey first to hold up two lenses placed some distance apart in order to bring an object's image closer. (Sadly, his patent request was denied.)

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1609

Galileo Galilei builds his first telescope

Observations establish the validity of the Copernican model of the universe.

1620

Mayflower lands

Merchant ship named the Mayflower sets sail from Plymouth, England and lands in November on the tip of Cape Cod.

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1620

Novum Organum (New Organon)

Francis Bacon. Recommends inductive reasoning and experimentation (consistent with empiricism as the means to obtain scientific knowledge, i.e. certainty) as the bases of the scientific method. Title is a reference to Aristotle's work, Organon, his treatise on logic.

1627

Brain and movement

William Harvey demonstrates in frogs that the brain plays a role in movement.

1628

On the Motion of the Heart and Blood

William Harvey describes the circulation of the blood.

1633

Galileo recants

The Roman Catholic Inquisition forces Galileo to rescind his Copernican view that the Earth moves around the Sun.

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1637

Discourse on the Method of Rightly Conducting One's Reason and of Seeking Truth in the Sciences

René Descartes. One of the most important works in the history of modern philosophy. Descartes describes his use of the "method of doubt" (deductive reasoning) to achieve certain (scientific) knowledge. Through this process he arrives at foundational beliefs, one of which is the existence of material bodies that exist independently of an immaterial mind (description of the modern mind-body problem). The book is consistent with philosophies of dualism and rationalism.

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1651

Leviathan

Thomas Hobbes's views on metaphysics (materialism) and human nature.

1658

First description of red blood cells

Jan Swimmerdam observes red blood cells under a microscope.

1662

Royal Society of London

Royal Society of London for Improving Natural Knowledge is chartered as a learned society of physicians and natural philosophers. It is the oldest existing such society today. The Royal Society and others like it are a very important part of the growth of science: such societies emerged in the 1600s to provide a forum for individuals to disseminate information about the natural sciences.

1663

René Descartes banned

René Descartes' works are placed on the Roman Catholic Church's Index of Prohibited Books.

1664

Electrical stimulation of muscles

Jan Swimmerdam uses electrical nerve stimulation to cause a frog's muscle to contract.

1664

Anatomy of the Brain

Thomas Willis. Most comprehensive and accurate description of the brain and nervous system to date.

1664

Treatise on Man

René Descartes' mechanistic model of humans.

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1677

Ethics

Baruch Spinoza. Philosophical work that, in the style of solving a geometic problem, addresses questions of God, the structure of reality, and moral philosophy. His position on the nature of mind is termed "double aspectism".

1682

Witch executions end in England

England conducts its last witch execution.

1687

The Mathematical Principles of Natural Philosophy (The Principia)

Isaac Newton. Perhaps the greatest of all scientific works, it is the culmination of theory regarding the universe and physics from Aristotle through Copernicus. It states Newton's laws of motion and law of universal gravitation. Is significant, too, for its underlying message: the language of mathematics helps us decipher the material world, not scripture. Authority lies with the scientific method, not the spiritual or divine.

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1690

An Essay Concerning Human Understanding

John Locke. Humans acquire knowledge through experience (repeated exposure) that has its origins in one source: sense data. Is consistent with the philosophy of empiricism.

1695

The Anatomy of the Brain Containing its Mechanisms and Physiology

Humphrey Ridley. First English-language treatise of neuroanatomy.

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1700 — 1800

The Scottish School

School of philosophical thought that influenced psychology (through works of Thomas Reid, Dugald Steward, and Thomas Brown). Many individuals who became faculty members at the newly created American universities followed tenets of this school.

1709

An Essay Towards a New Theory of Vision

George Berkeley's empirical theory of vision that contrasted with standard accounts of the day (based on geometric calculations). Berkeley's account is that we cannot actually "see" the distance of objects; instead, the association of ideas of sight and touch explains how we perceive distance.

1710

A Treatise Concerning the Principles of Human Knowledge

George Berkeley's empiricist argument that knowledge derives from the experience of one's own mind (ideas), rather than physical objects. The text supports two metaphysical positions: idealism (all that exists is a mind or depends on mind for its existence) and immaterialism (matter does not exist).

1714

The Monadology

Gottfried Wilhelm Leibniz. A metaphysics of substance (psychophysical parallelism).

1739

A Treatise of Human Nature

David Hume. Addresses the problem of human knowledge, the passions, and morals.

1748

An Enquiry Concerning Human Understanding

David Hume. Ideas and impressions as a source of experience, the laws of association, and an influential analysis of the concept of causation as a product of association.

1749

Observations on Man, his Frame, his Duty, and his Expectations

David Hartley's work is the first attempt to adopt association as the fundamental operation of all ideas and behaviors. Explains how mental associations are formed and identifies neurophysiological activity as their origin.

1751

First volume of Encyclopedia, or Rational dictionary of science, art, and custom

First volume of what is more generally known as the Encyclopedia, published by Jean le Rond d'Alembert and Denis Diderot.

1754

Treatise on Sensations

Étienne Bonnot de Condillac. Knowledge reaches humans only through the senses.

1757

Elements of the Physiology of the Human Body

Albrecht von Haller. Surveys physiological knowledge of the time and describes Haller's studies on muscles and human blood circulation.

1758

Essays on the Mind

Claude Adrien Helvetius. Mind develops as a result of sensations it perceives, not as a product of innate tendencies.

1764

Observations on nervous, hypochondriacal, or hysteric diseases

Robert Whytt. One of the first important textbooks on neurology.

1766

Nerves control muscle contraction

Albrecht von Haller shows that nerves stimulate muscle contraction and all nerves lead to spinal cord and brain.

1776

Declaration of Independence signed

Expresses the ideals on which the United States was founded and its reasons for separation from Great Britain.

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1781

Critique of Pure Reason

Immanuel Kant. One of the most important works in philosophy for its analysis of the nature of metaphysics.

1789

French Revolution begins

A citizen mob storms the Bastille prison in Paris on July 14.

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1792

A Vindication of the Rights of Woman

Mary Wollstonecraft. One of the earliest works of feminist philosophy.

1802

Color vision

Thomas Young suggests that the ability to perceive color depends on the presence of three types of nerves in the retina.

1805

On the activities of the brain

Franz Joseph Gall incorrectly argues that the brain can be studied by examining the contours of a person's skull—phrenology. (His underlying assumption that different parts of the brain generally do have different functions was accurate.)

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1806

A Treatise on Insanity

Philippe Pinel. Provides an improved classification for mental illness and an argument for moral (talk) therapy.

1809

Zoological Philosophy

Jean-Baptiste Lamarck. Describes a theory of inheritance of acquired characteristics (first complete theory of evolution) that was eventually discredited.

1811

Idea of a New Anatomy of the Brain

Charles Bell. Describes the difference between sensory and motor nerves. Bell's Law: the anterior spinal roots are motor and the posterior roots are sensory (also Bell-Magendie Law).

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1812

Medical Inquiries and Observations Upon the Diseases of the Mind

Benjamin Rush. First textbook of psychopathology in America.

1816

Textbook of Psychology

Johann Herbart.

1821

Copernicus ban lifted

The Roman Catholic Church lifts its ban on teaching Copernican physics.

1824 — 1825

Psychology as a Science

Johann Herbart. Mathematical expression of laws by which mental representations (ideas) interact. Describes ideas in terms of equilibrium and mechanics ("force", "inhibition").

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1826

Sensation, perception, physiology

Ernst Heinrich Weber begins experiments with the two-point threshold of sensation.

1829

An Analysis of the Phenomena of the Human Mind

James Mill's mechanistic/associationist account of mental processes.

1830

The Course in Positive Philosophy

Six-volume work by Auguste Comte establishes positivism as philosophical school.

1831

Beginnings of social statistics

Lambert Adophe Jacques Quetelet studies how variables such as gender, age, education, climate and season affect the crime rate in France.

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1833

Handbook of Physiology

Johannes Peter Müller proposes theory that each nerve has its own specific energy (doctrine of specific nerve energies).

1834

Weber's Law

Ernst Weber. The change in stimulus intensity that can just be discriminated is a constant ratio of the initial intensity of the physical stimulus. In other words, the more intense the stimulus, the greater the change that must be made in it to be noticed.

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1835

HMS Beagle

Charles Darwin travels to Galapagos Islands as scientific officer on the ship. Observes that closely related finches seem to have descended from a common ancestor on the South American mainland.

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1841

Dorothea Dix brings attention to plight of people with mental illness

Begins her investigations into the treatment of people with mental illness in Massachusetts.

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1850

Speed of a nerve impulse

Hermann von Helmholtz is first scientist to make precise measurements of nervous action.

1850

Interest in comparative psychology emerges

See works of George Romanes, Conwy Lloyd Morgan.

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1850

Fechner Day

October 22. Gustav Fechner realizes that he can address the mind-body problem by comparing physical measures and psychological appearances. He investigated psychophysics for the rest of his life, laying the foundation for experimental psychology.

1859

On the Origin of Species

Charles Darwin

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1860

Weber-Fechner Law

Gustav Fechner's adaptation of Weber's Law. Establishes a scale of sensation magnitude having a zero-point value and a basic unit of measurement (just noticeable difference [JND]). Significance: sensation magnitude can be measured indirectly by relating values of change on the physical scale to corresponding values on a psychological scale (the JND difference in sensation).

1860

The Elements of Psychophysics

Gustav Fechner. One of the most important books in the history of psychology. Describes conceptual issues in measuring physical and psychological worlds, Fechner's own experimental work, and psychophysical methods.

1861

Broca's Area established

Pierre Paul Broca demonstrates that loss of speech is related to a lesion in the left frontal lobe.

1861 — 1865

American Civil War

Confederate States of America formed by South Carolina and ten other Southern states. First battle at Bull Run is a Confederate victory.

1862

Treatment of nervous system disorders at La Salpêtriėre, Paris

Jean-Martin Charcot begins his clinical studies of nervous system disorders, including hysteria.

1863

Reflexes of the Brain

I. M. Sechenov attempts to analyze higher-order functions in terms of the reflex action. Reflects the Russian objective psychology that later influences American behaviorism.

1863

National Academy of Sciences

Group of scientists based largely in Cambridge, Massachusetts solicited the Massachusetts senator to draft a bill of incorporation.

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1864

Principles of Biology

Herbert Spencer. Coins term "survival of the fittest"".

1865

Laws of genetics

Gregor Mendel publishes his theories of genetics.

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1869

Hereditary Genius

Francis Galton publishes his work in historiometry

1870

First direct stimulation of the brain

Gustave T. Fritsch and Julius Eduard Hitzig discover that the cerebral cortex has different compartments for different functions and introduce electrical stimulation as a means to study the brain.

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1873 — 1874

Principles of Physiological Psychology

Wilhelm Wundt's lecture notes organized into chapters. One of the most important works in the history of psychology.

1876

Functions of the Brain

David Ferrier. Collections of experiments on brain localization, regarded as among the most important advances in physiology at the time of its publication.

1877

Lectures on the Diseases of the Nervous System

Jean-Martin Charcot

1879

Psychology becomes an experimental science

Wilhelm Wundt founds the first psychological laboratory at the University of Leipzig, Germany.

1879

Mind

First journal devoted to psychological research. Created by Alexander Bain.

1881

Philosophical Studies

Outlet for research from Wundt's laboratory. First academic journal for psychological research.

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1885

Sigmund Freud studies with Jean-Martin Charcot at La Salpêtriėre

His observations of Charcot's hypnotic treatment of hysteria will greatly influence Freud's later ideas and the development of psychoanalysis.

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1885

On Memory

Hermann Ebbinghaus's foundational work on memory that includes his "curve of forgetting" (how much is retained in human memory over time).

1888

Concept of correlation ("co-relation")

Francis Galton describes the interdependence of two sets of variables.

1890

On Gestalt Qualities

Chistian von Ehrenfels. First proposal of Gestalt concept.

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1890

Principles of Psychology

William James writes textbook that surveys major topics of study in psychology at the time. Book will be used in American universities for decades.

1892

American Psychological Association

G. Stanley Hall instrumental in creating this professional society.

1892 — 1924

Ellis Island and the nation's immigrants

12 million European immigrants arrive at this New York City inspection station during this period. This event can be viewed as a factor in the emergence of the mental testing movement.

1893

World's Columbian Exposition, Chicago, Illinois

Psychology is recognized as an official exhibit at this celebration of American culture. Visitors can view a collection of psychological instruments and pay a fee to access a testing room to have their mental and sense powers assessed.

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1893 — 1901

Early experimental methods handbooks

E. B. Titchener and Edmund Sanford produce textbooks for university use.

1893 — 1895

Studies on Hysteria

Sigmund Freud and Josef Breuer. Technical procedures (Breuer's cathartic method) and clinical findings addressed in the book will influence Freud to adopt psychoanalysis as a treatment for hysteria.

1894

Pullman strike

Pullman railroad car plant in Chicago is the site of a violent workers' strike. Symbolic of labor unrest throughout the nation in the late 1800s. American functionalists see the potential for psychological science to help alleviate such real-world problems.

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1894

First woman to earn PhD in psychology

Margaret Floy Washburn

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1895

Mary Whiton Calkins

Unofficially defends her dissertation at Harvard University.

1896

The Reflex Arc Concept in Psychology

John Dewey. Establishes key tenet of American functionalism: an emphasis on the role of adaptation in an organism's behavior.

1898

The Postulates of a Structural Psychology

E. B. Titchener. Establishes structuralism as a psychological school of thought.

1904

The Experimentalists

E. B. Titchener begins a small, elite scientific society to promote psychology as an experimental science. Membership closed to female or non-experimental psychologists.

1905

Mary Whiton Calkins

First woman president of the American Psychological Association.

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1905

First usable intelligence test created

Alfred Binet and Théodore Simon

1907

The Province of Functional Psychology

James Rowland Angell's description of the psychology practiced by several prominent psychologists at various American universities. Contrasts with Titchener's structuralism.

1907

The Psychological Clinic

Lightner Witmer establishes the only clinical psychology journal of the time and it becomes instrumental in shaping this subfield.

1908

A Mind that Found Itself

Clifford Beers's autobiographical account of his experiences as a patient in an asylum. The book inspired the mental hygiene movement in the United States.

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1908

On the Witness Stand

Hugo Münsterburg. Psychology as applied to courts, legal system. Reflects a tenet of American functionalist thought: psychological methods should be applied to practical problems outside the laboratory.

1909

Freud's first and only visit to America

G. Stanley Hall organizes the Clark University Conference at which Freud is an invited speaker.

1909

NAACP established

National Association for the Advancement of Colored People established in the United States.

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1911

Animal Intelligence

E. L. Thorndike

1912

The intelligence quotient

William Stern labels the mental age divided by the chronological age the 'intelligence quotient'. (Lewis Terman will later abbreviate to IQ.)

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1912

Phi phenomenon

Max Wertheimer. Publication titled Experimental Studies of the Perception of Movement is a foundational document for the Gestalt system of thought.

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1913

Psychology as the Behaviorist Views It

John B. Watson's description of tenets of behaviorism. Usually cited as the origin of behaviorism.

1914 — 1918

World War I begins

Archduke Franz Ferdinand of Austria is assassinated.

1917

United States declares war on Germany

American enters WW I.

1917

Psychology and WW I

Robert Yerkes introduces Army Alpha and Army Beta tests. Tests are used to screen potential military recruits for fitness to serve.

1919

Treaty of Versailles

Peace treaty that ended the state of war between Germany and the Allied powers.

1920

Nineteenth Amendment to the US Constitution

Voting rights legally guaranteed for American women.

1920

Fear is a conditioned response

Study by J. Watson and R. Rayner that demonstrated that an emotional reaction could be learned via classical conditioning. Consistent with behaviorism.

1920

First African American doctorate in psychology

Frances Cecil Sumner at Clark University

1921

Acetylcholine confirmed as first neurotransmitter

Otto Loewi

1921

Rorschach test created

Hermann Rorschach develops personality test based on interpretation of inkblots.

1921

American Birth Control League established

Margaret Sanger reponsible for establishing the organization which would eventually become the Planned Parenthood Federation of America.

1924 — 1933

Hawthorne experiments

Managers at the Hawthorne works of Western Electric Company (Illinois) collaborate with Elton Mayo and Fritz Roethlisberger at the Harvard Business School to conduct experiments on variables such as worker productivity and job satisfaction. Studies reflect the growing belief that scientific methods could be applied to real-world settings. The research uncovered the "Hawthorne effect": humans will alter their behavior in response to knowledge that they are under observation.

1925

Scopes monkey trial

State of Tennessee v. John Thomas Scopes. Nationally publicized trial which pits evolutionary theory against biblical scripture when a high school teacher agrees to be tried for violating state law that prohibited teaching evolution in public schools. Scopes was found guilty and fined and the verdict was later overturned.

1925

Menninger Clinic founded

Charles Frederick Menninger and sons open clinic emphasizing psychiatry and psychology in treatment of mental illness.

1927

The Logic of Modern Physics

Percy W. Bridgman argues that all physical concepts must be defined in precise terms and that concepts lacking physical references must be discarded.

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1927

Conditioned Reflexes

Ivan Pavlov's physiological studies of digestion in dogs are the foundation of classical conditioning and an influence on the development of American behaviorism.

1929 — 1939

Great Depression

New York stock market crashes and begins Great Depression.

1929

Electroencephalogram invented

Psychiatrist Hans Berger invents instrument to graph electrical activity of the brain.

1933 — 1945

Adolf Hitler is elected Chancellor of Germany

Will remain Chancellor through the end of World War II.

1935

Alcoholics Anonymous founded

Bill Wilson and Dr. Robert Smith establish treatment model for addiction that features social support groups.

1936

First human frontal lobotomy

Egan Moniz

1936

Model of computability

Alan M. Turing publishes a paper which introduces the concept of a Turing Machine.

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1937

The Neurotic Personality of Our Time

Karen Horney. Publication reflects psychoanalytic theory among psychoanalytic theorists following Freud.

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1938

The Behavior of Organisms

B. F. Skinner (behaviorism)

1938

First use of electroshock therapy

Ugo Cerletti and Lucino Bini

1939 — 1945

World War II begins

Germany invades Poland.

1941

United States enters World War II

United States declares war on Axis powers following bombing of Pearl Harbor by Japanese.

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1942

Counseling and Psychotherapy

Carl Rogers. Exemplifies tenets of humanistic psychology.

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1943

A Theory of Human Motivation

Abraham Maslow. Journal publication that exemplifies tenets of humanistic psychology.

1946

Mental Health Act passed

President Harry S. Truman signs law that funds psychiatric education and research for first time in United States history.

1948

Male and Female: A Study of the Sexes in a Changing World

Margaret Mead's claim that many aspects of Western culture are a product of Western child-rearing practices.

1949

Leucotomy

Egas Moniz awarded Nobel Prize in Physiology or Medicine for the therapeutic procedure he developed for psychosis.

1949

Information theory

Claude Shannon publishes his mathematical theory of information.

1949

Recommendation that doctoral programs train clinical psychologists as research-practitioners

Boulder Conference on Graduate Education in Clinical Psychology

1950

Childhood and Society

Erik Erikson. Publication reflects psychoanalytic theory among psychoanalytic theorists following Freud.

1951

Client-Centered Therapy

Carl Rogers. Exemplifies tenets of humanistic psychology.

1952

First edition of the Diagnostic and Statistical Manual of Mental Disorders published

American Psychiatric Association

1953

DNA modeled

James Dewey Watson and Francis H. Crick develop the double-helix model for deoxyribonucleic acid (DNA). Explains how the molecule can transmit heredity in living organisms.

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1954

The Nature of Prejudice

Gordon Allport. Book helped to promote the study of prejudice.

1954

Army-McCarthy hearings

Concern over Communist Party presence in America culminates in Army-McCarthy hearings before the US Senate.

1954

Brown v. Board of Education

United States Supreme Court declares that laws establishing separate public schools for black and white students are unconstitutional.

1956

Information theory applied to cognitive processes

George Miller reviews research findings and concludes that they can be explained by information theory.

1959

Chomsky's review of Skinner's Verbal Behavior

Linguist Noam Chomsky writes a powerful critique of B. F. Skinner's book (behavioral principles cannot explain language acquisition). Supports growing sentiment that a purely behavioral explanation of human functioning is not valid.

1960

Behavior Genetics

John L. Fuller and W. Robert Thompson. Text inspired interest in modern genetic theory as it applies to inherited behavior.

1960

Interest in cultural factors in psychological processes intensifies

Culture becomes a topic of research programs across a critical mass of scholars. For seminal studies, see, for instance, individual and collaborative works by D. C. McClelland, J. W. Berry, R. Benedict, M. H. Segall, and M. J. Herskovits.

1961

The Myth of Mental Illness

Thomas Szasz writes a powerful critique of his psychiatric profession.

1961

Journal of Humanistic Psychology

Journal is a forum for psychologists who advocate a perspective on psychology that is an alternative ("third force") to the dominant schools of thought (behaviorism and psychoanalysis).

1961

Humans venture into the last frontier

Russian cosmonaut Yuri Gagarin becomes first man in space.

1963

March on Washington

Martin Luther King, Jr. delivers his historic "I Have a Dream" speech in front of the Lincoln Memorial to call for an end to racism.

1963

Community Mental Health Centers Act passed

President John F. Kennedy signs act that funds construction of community-based centers for psychiatric treatment. Program ends in 1981.

1963

Cognitive therapy established

Aaron T. Beck's 1963 article "Thinking and depression: Idiosyncratic content and cognitive distortions" is central to theory and research on cognitive techniques for treating mental illness.

1963

The Feminine Mystique

Betty Friedan's book greatly influenced a mid-century interest in feminism.

1964

Civil Rights Act passed in United States

President Lyndon B. Johnson signs bill that outlaws discrimination based on race, color, religion, sex, or national origin.

1964

First National Medal of Science awarded to psychologist

Neal E. Miller for studies of motivation and learning.

1965 — 1973

United States involvement in the war in Vietnam

General American reaction is one of protest.

1965

Harlow's monkeys

Harry Harlow's experimental research demonstrates that monkeys reared in isolation exhibit great emotional impairment later in their development.

1966

National Organization for Women

Feminist organization established to ensure legal enforcement of national anti-discrimination laws already in place.

1967

Cognitive Psychology

Ulric Neisser's perspective on psychology that focuses on the operation of mental processes.

1967

Split brain research

Michael S. Gazzinga reports that studies of people whose brain halves have been severed show that the two halves can function independently

1968

Association of Black Psychologists

Established as a forum through which African American psychologists could address professional needs neglected by existing organizations.

1969

Neil Armstrong and Buzz Aldrin land on moon

Apollo 11 successfully places a manned vehicle on the moon.

1973

Homosexuality removed from Diagnostic and Statistical Manual of Mental Disorders

Professional conceptualization of people who are homosexual or bisexual is no longer one of illness.

1973

Nobel Prize for research in social behavior

Karl von Frisch, Konrad Lorenz, and Nikolass Tinbergen jointly awarded the Nobel Prize in Physiology or Medicine for their ethological studies.

1975

Sociobiology: The New Synthesis

E. O. Wilson's controversial book introduces "sociobiology" as the study of the biological basis of social behavior. Influential in development of evolutionary psychology.

1976

The Selfish Gene

Richard Dawkins's book shifts focus from evolutionary change at the level of either the species or organism to evolutionary change at the level of the gene. Popularizes evolutionary psychology.

1978

Society for Health Psychology

Division 38 of the American Psychological Association established.

1978

Nobel Prize for decision-making research

Herbert Simon awarded the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel for research in decision-making within economic organizations.

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1979

Eyewitness Testimony

Elizabeth Loftus. Review of psychological research that argues against the use of eyewitness testimony.

1979

Larry P. v Wilson Riles

U. S. District Court decision that finds that IQ tests discriminate against African American students.

1979

The Ecological Approach to Perception

Book represents the culmination of the theory and research by J. J. Gibson who advocates that cognitive processes are not necessary for an organism to perceive—information from an observer's environment is the critical component in perception. Significant work in visual perception and ecological psychology.

1981

Assassination attempt on Ronald Reagan

John W. Hinckley shoots four individuals in an attempt to assassinate President Reagan. Event is a factor in the Insanity Defense Reform Act of 1984 which makes it difficult to obtain a verdict of not guilty by reason of insanity in the United States.

1981

Nobel Prize for advances in cerebral function research

Roger W. Sperry shares the Nobel Prize in Physiology or Medicine for discoveries concerning functional specialization in cerebral hemispheres.

1981

Nobel Prize for information processing research

David H. Hubel and Torsten N. Wiesel share the Nobel Prize (with R. W. Sperry) in Physiology or Medicine for discoveries concerning information processing in the visual system.

1981

The Mismeasure of Man

Stephen Jay Gould's critique of biological determinism.

1981

Computers come to the people

The IBM personal computer (and the industry-standard disk operating system [DOS]) is introduced.

1983

Frames of Mind: The Theory of Multiple Intelligences

Theory of multiple intelligences by Howard Gardner.

1984

DNA successfully cloned

University of California scientists Allan Wilson and Russell Higuchi successfully clone DNA from an extinct animal.

1985

Society for the Psychological Study of Lesbian, Gay, Bisexual and Transgender Issues

Division 44 of the American Psychological Association established.

1986

Society for the Psychological Study of Culture, Ethnicity and Race

Division 45 of the American Psychological Association established.

1986

Society for Sport, Exercise and Performance Psychology

Division 47 of the American Psychological Association established.

1986

Prozac enters medical use for mental illness

Fluoxetine prescribed for depression.

1988

American Psychological Society established

Professional association for the advancement of psychology as a science. Known now as Association for Psychological Science.

1991

Learned Optimisn

Martin Seligman. Establishes positive psychology movement.

1997

International Psychology

Division 52 of the American Psychological Association established.

2000

Nobel Prize for nervous system research

The Nobel Prize in Physiology or Medicine jointly awarded to Arvid Carlsson and Paul Greengard (dopamine actions) and Eric R. Kandel (synapses and memory).

2000

Scientists map human genome

World's largest collaborative biological project completes a draft of the genome.

2001

Terrorist attacks in United States

Islamic terrorist group coordinates two attacks (hijacked air carriers) on the United States (New York City, the Pentagon, and a thwarted attempt in Washington, DC).

2002

Nobel Prize for judgment and decision-making research as applied to economic theory

Psychologist Daniel Kahneman jointly receives Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel.

2006

PsycINFO goes digital

Final publication of Psychological Abstracts, bibliographic index to the world's literature in psychology. The print product is continued as the electronic database, PsycINFO.

2013

Fifth edition of the DSM published

American Psychiatric Association revises its classification system for mental disorders and includes diagnostic guidelines based on impairments in functioning and unhealthy (extreme) personality traits.

 
Cosmologists (Pre-Socratics)
600 BCE — 469 BCE

Cosmologists (Pre-Socratics)

Alcmaeon

Plato

Aristotle

De Anima "On the Soul"

Roman philosophy

Roman Empire begins

Almagest

Galen

pneuma theory

St. Augustine

Christianity is official religion of Rome

Roman Empire (Western) ends

Carolingian Europe is a stable Europe

Islamic Golden Age

Western Europe destabilizes

Conditions ripe in Europe for intellectual activity

First Crusades

Enormous intellectual activity in Europe

European universities emerge

Charter granted to University of Bologna (Italy)

Charter granted to University of Paris

Aristotle banned

Magna Carta signed

Thomas Aquinas and Scholasticism

Charter granted to University of Cambridge

Charter granted to University of Oxford

Renaissance

Renaissance Humanism

Black Plague

End of the medieval period

Bethlem Hospital cares for mentally ill

First use (?) of term "psychology" to denote the science of mental life

Byzantine Empire (Eastern Roman) ends

The Malleus Maleficarium

Old World meets New World

Protestant Reformation begins

Start of Scientific (Copernican) Revolution

On the Revolutions of the Celestial Spheres

On the Structure of the Human Body

University of Edinburgh

European settlement of the Americas

First telescope invented

Galileo Galilei builds his first telescope

Mayflower lands

Novum Organum (New Organon)

Brain and movement

On the Motion of the Heart and Blood

Galileo recants

Discourse on the Method of Rightly Conducting One's Reason and of Seeking Truth in the Sciences

Leviathan

First description of red blood cells

Royal Society of London

René Descartes banned

Electrical stimulation of muscles

Anatomy of the Brain

Treatise on Man

Ethics

Witch executions end in England

The Mathematical Principles of Natural Philosophy (The Principia)

An Essay Concerning Human Understanding

The Anatomy of the Brain Containing its Mechanisms and Physiology

The Scottish School

An Essay Towards a New Theory of Vision

A Treatise Concerning the Principles of Human Knowledge

The Monadology

A Treatise of Human Nature

An Enquiry Concerning Human Understanding

Observations on Man, his Frame, his Duty, and his Expectations

First volume of Encyclopedia, or Rational dictionary of science, art, and custom

Treatise on Sensations

Elements of the Physiology of the Human Body

Essays on the Mind

Observations on nervous, hypochondriacal, or hysteric diseases

Nerves control muscle contraction

Declaration of Independence signed

Critique of Pure Reason

French Revolution begins

A Vindication of the Rights of Woman

Color vision

On the activities of the brain

A Treatise on Insanity

Zoological Philosophy

Idea of a New Anatomy of the Brain

Medical Inquiries and Observations Upon the Diseases of the Mind

Textbook of Psychology

Copernicus ban lifted

Psychology as a Science

Sensation, perception, physiology

An Analysis of the Phenomena of the Human Mind

The Course in Positive Philosophy

Beginnings of social statistics

Handbook of Physiology

Weber's Law

HMS Beagle

Dorothea Dix brings attention to plight of people with mental illness

Speed of a nerve impulse

Interest in comparative psychology emerges

Fechner Day

On the Origin of Species

Weber-Fechner Law

The Elements of Psychophysics

Broca's Area established

American Civil War

Treatment of nervous system disorders at La Salpêtriėre, Paris

Reflexes of the Brain

National Academy of Sciences

Principles of Biology

Laws of genetics

Hereditary Genius

First direct stimulation of the brain

Principles of Physiological Psychology

Functions of the Brain

Lectures on the Diseases of the Nervous System

Psychology becomes an experimental science

Mind

Philosophical Studies

Sigmund Freud studies with Jean-Martin Charcot at La Salpêtriėre

On Memory

Concept of correlation ("co-relation")

On Gestalt Qualities

Principles of Psychology

American Psychological Association

Ellis Island and the nation's immigrants

World's Columbian Exposition, Chicago, Illinois

Early experimental methods handbooks

Studies on Hysteria

Pullman strike

First woman to earn PhD in psychology

Mary Whiton Calkins

The Reflex Arc Concept in Psychology

The Postulates of a Structural Psychology

The Experimentalists

Mary Whiton Calkins

First usable intelligence test created

The Province of Functional Psychology

The Psychological Clinic

A Mind that Found Itself

On the Witness Stand

Freud's first and only visit to America

NAACP established

Animal Intelligence

The intelligence quotient

Phi phenomenon

Psychology as the Behaviorist Views It

World War I begins

United States declares war on Germany

Psychology and WW I

Treaty of Versailles

Nineteenth Amendment to the US Constitution

Fear is a conditioned response

First African American doctorate in psychology

Acetylcholine confirmed as first neurotransmitter

Rorschach test created

American Birth Control League established

Hawthorne experiments

Scopes monkey trial

Menninger Clinic founded

The Logic of Modern Physics

Conditioned Reflexes

Great Depression

Electroencephalogram invented

Adolf Hitler is elected Chancellor of Germany

Alcoholics Anonymous founded

First human frontal lobotomy

Model of computability

The Neurotic Personality of Our Time

The Behavior of Organisms

First use of electroshock therapy

World War II begins

United States enters World War II

Counseling and Psychotherapy

A Theory of Human Motivation

Mental Health Act passed

Male and Female: A Study of the Sexes in a Changing World

Leucotomy

Information theory

Recommendation that doctoral programs train clinical psychologists as research-practitioners

Childhood and Society

Client-Centered Therapy

First edition of the Diagnostic and Statistical Manual of Mental Disorders published

DNA modeled

The Nature of Prejudice

Army-McCarthy hearings

Brown v. Board of Education

Information theory applied to cognitive processes

Chomsky's review of Skinner's Verbal Behavior

Behavior Genetics

Interest in cultural factors in psychological processes intensifies

The Myth of Mental Illness

Journal of Humanistic Psychology

Humans venture into the last frontier

March on Washington

Community Mental Health Centers Act passed

Cognitive therapy established

The Feminine Mystique

Civil Rights Act passed in United States

First National Medal of Science awarded to psychologist

United States involvement in the war in Vietnam

Harlow's monkeys

National Organization for Women

Cognitive Psychology

Split brain research

Association of Black Psychologists

Neil Armstrong and Buzz Aldrin land on moon

Homosexuality removed from Diagnostic and Statistical Manual of Mental Disorders

Nobel Prize for research in social behavior

Sociobiology: The New Synthesis

The Selfish Gene

Society for Health Psychology

Nobel Prize for decision-making research

Eyewitness Testimony

Larry P. v Wilson Riles

The Ecological Approach to Perception

Assassination attempt on Ronald Reagan

Nobel Prize for advances in cerebral function research

Nobel Prize for information processing research

The Mismeasure of Man

Computers come to the people

Frames of Mind: The Theory of Multiple Intelligences

DNA successfully cloned

Society for the Psychological Study of Lesbian, Gay, Bisexual and Transgender Issues

Society for the Psychological Study of Culture, Ethnicity and Race

Society for Sport, Exercise and Performance Psychology

Prozac enters medical use for mental illness

American Psychological Society established

Learned Optimisn

International Psychology

Nobel Prize for nervous system research

Scientists map human genome

Terrorist attacks in United States

Nobel Prize for judgment and decision-making research as applied to economic theory

PsycINFO goes digital

Fifth edition of the DSM published

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