Christine Ladd-Franklin (December 1, 1847 – March 5, 1930) was an American
psychologist
A psychologist is a professional who practices psychology and studies mental states, perceptual, cognitive, emotional, and social processes and behavior. Their work often involves the experimentation, observation, and interpretation of how indi ...
,
logician
Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premises ...
, and
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems.
Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change.
History
On ...
.
Early life and education
Christine Ladd, sometimes known by her nickname "Kitty",
was born on December 1, 1847, in
Windsor
Windsor may refer to:
Places Australia
* Windsor, New South Wales
** Municipality of Windsor, a former local government area
* Windsor, Queensland, a suburb of Brisbane, Queensland
**Shire of Windsor, a former local government authority around Wi ...
, Connecticut, to Eliphalet, a merchant, and Augusta (
née
A birth name is the name of a person given upon birth. The term may be applied to the surname, the given name, or the entire name. Where births are required to be officially registered, the entire name entered onto a birth certificate or birth re ...
Niles) Ladd. During her early childhood, she lived with her parents and younger brother Henry (born 1850) in New York City.
In 1853 the family moved back to Windsor, Connecticut, where her sister Jane Augusta Ladd McCordia was born the following year. Family correspondence shows that Augusta and one of her sisters were both staunch supporters of
women's rights
Women's rights are the rights and entitlements claimed for women and girls worldwide. They formed the basis for the women's rights movement in the 19th century and the feminist movements during the 20th and 21st centuries. In some countries, ...
. Even before Ladd had celebrated her fifth birthday, her mother had taken her to a lecture given by
Elizabeth Oakes Smith
Elizabeth Oakes Smith ( Prince; August 12, 1806 – November 16, 1893) was a poet, fiction writer, editor, lecturer, and women's rights activist whose career spanned six decades, from the 1830s to the 1880s. Most well-known at the start of her ...
, a well-known proponent of women's rights. Additionally, her father was a graduate professor who was supportive of his eldest daughter's education.
[
Following the death of her mother in spring 1860 of pneumonia, Ladd went to live with her paternal grandmother in ]Portsmouth
Portsmouth ( ) is a port and city in the ceremonial county of Hampshire in southern England. The city of Portsmouth has been a unitary authority since 1 April 1997 and is administered by Portsmouth City Council.
Portsmouth is the most dens ...
, New Hampshire, where she attended school.[ Ladd's father remarried in 1862 and had two further children, her half-sister Katherine (born 1862) and half-brother George (born 1867).][ Ladd was a precocious child who sought to find "a mean to continue her education beyond secondary school."][ Her father enrolled her in a two-year program at the coeducational Wesleyan Academy in Wilbraham, Massachusetts. At Wesleyan Academy she took the same courses her male classmates took to prepare for entrance to colleges such as ]Harvard
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...
.
In 1865 Ladd graduated as valedictorian
Valedictorian is an academic title for the highest-performing student of a graduating class of an academic institution.
The valedictorian is commonly determined by a numerical formula, generally an academic institution's grade point average (GPA ...
from Wesleyan Academy and pursued further education at Vassar College
Vassar College ( ) is a private liberal arts college in Poughkeepsie, New York, United States. Founded in 1861 by Matthew Vassar, it was the second degree-granting institution of higher education for women in the United States, closely follo ...
, supported by her family.
In the fall of 1866 Ladd enrolled in Vassar College financed by a loan from her aunt, Juliet Niles, but left at the end of the spring term due to financial hardship.[ Ladd then worked as a public school teacher until her aunt's aid allowed her to re-enter Vassar and graduate with an A.B. degree in 1869. While attending Vassar, Ladd began working under the mentorship of astronomy professor, ]Maria Mitchell
Maria Mitchell ( /məˈraɪə/; August 1, 1818 – June 28, 1889) was an American astronomer, librarian, naturalist, and educator. In 1847, she discovered a comet named 1847 VI (modern designation C/1847 T1) that was later known as " Miss Mi ...
, who was famous for having been "the first woman to discover a new comet, using a telescope, in 1847". Mitchell was also a suffragette
A suffragette was a member of an activist women's organisation in the early 20th century who, under the banner "Votes for Women", fought for the right to vote in public elections in the United Kingdom. The term refers in particular to members ...
and strove to inspire women to gain more self-confidence to enter into the male-dominated academia of the time. Under the guidance of Mitchell, Ladd became proficient and developed a love for physics and mathematics. Since women in nineteenth-century America were not allowed in physics laboratories, Ladd chose to study mathematics. Later in her life, Ladd would reflect on her decision and say, "had it not been for the impossibility, in those days, in the case of women, of obtaining access to laboratory facilities" she would have eagerly gone on to study physics.
In 1887 Vassar College awarded Ladd an honorary LL.D.
Legum Doctor (Latin: “teacher of the laws”) (LL.D.) or, in English, Doctor of Laws, is a doctorate-level academic degree in law or an honorary degree, depending on the jurisdiction. The double “L” in the abbreviation refers to the early ...
Early career
After graduating, Ladd taught science and mathematics at secondary level in Washington, Pennsylvania
Washington is a city in and the county seat of Washington County, Pennsylvania. A part of the Greater Pittsburgh area in the southwestern part of the state, the city is home to Washington & Jefferson College and Pony League baseball. The populat ...
; Hollidaysburg, Pennsylvania
Hollidaysburg is a borough in and the county seat of Blair County in the U.S. state of Pennsylvania. It is located on the Juniata River, south of Altoona and is part of the Altoona, Pennsylvania, metropolitan statistical area. In 1900, 2,998 ...
; Massachusetts; and New York for nine years, although her diary entries indicate that her interest in teaching diminished over time. During this time, she contributed seventy-seven mathematical problems and solutions to the ''Educational Times'' of London
London is the capital and largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a majo ...
. She also published six items in ''The Analyst: A Journal of Pure and Applied Mathematics'' and three in the ''American Journal of Mathematics
The ''American Journal of Mathematics'' is a bimonthly mathematics journal published by the Johns Hopkins University Press.
History
The ''American Journal of Mathematics'' is the oldest continuously published mathematical journal in the United ...
''.[
]
Graduate education
In 1878, Ladd was accepted into Johns Hopkins University
Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hem ...
with the help of James J. Sylvester, an English mathematician among the university's faculty who remembered some of Ladd's earlier works in the ''Educational Times''.[ Ladd's application for a fellowship was signed "C. Ladd", and the university offered it to her without realizing she was a woman.] When they did realize this, the board tried to revoke the offer, but Sylvester insisted that Ladd should be his student, and so she was.[ She held a fellowship at Johns Hopkins University for three years, but the trustees did not allow her name to be printed in circulars with those of other fellows, for fear of setting a precedent.][ Furthermore, dissension over her continued presence forced one of the original trustees to resign.][
Since the university did not approve of coeducation, at first Ladd was only allowed to attend classes taught by Sylvester. However, after displaying exceptional work in his courses, Ladd was allowed to take courses with additional professors. Even though she was awarded a stipend, she was not allowed to have the title of "]fellow
A fellow is a concept whose exact meaning depends on context.
In learned or professional societies, it refers to a privileged member who is specially elected in recognition of their work and achievements.
Within the context of higher education ...
". During 1879 and 1880, Ladd took classes taught by Charles Sanders Peirce
Charles Sanders Peirce ( ; September 10, 1839 – April 19, 1914) was an American philosopher, logician, mathematician and scientist who is sometimes known as "the father of pragmatism".
Educated as a chemist and employed as a scientist for t ...
, who has been called the first American experimental psychologist.[ She wrote a dissertation "On the Algebra of Logic" with Peirce as her thesis advisor. The dissertation was published in ''Studies in Logic'' (C.S. Peirce, ed.) in 1883. In 1884 Ladd attended ]William Thomson, 1st Baron Kelvin
William Thomson, 1st Baron Kelvin, (26 June 182417 December 1907) was a British mathematician, mathematical physicist and engineer born in Belfast. Professor of Natural Philosophy at the University of Glasgow for 53 years, he did important ...
's master class
A master class is a Class (education), class given to students of a particular Academic discipline, discipline by an expert of that discipline—usually music, but also science, painting, drama, games, or on any other occasion where skills are b ...
and met her future husband, Fabian Franklin
Fabian Franklin (1853–1939) was a Hungarian-born American engineer, mathematician and journalist, husband of Christine Ladd-Franklin.
Life and work
The Franklin family (his parents were born in Poland) migrated from Hungary to Philadelphia ...
.
Due to her studies with Sylvester and Peirce, Ladd became the first American woman to formally receive graduate instruction in both mathematics and symbolic logic
Mathematical logic is the study of formal logic within mathematics. Major subareas include model theory, proof theory, set theory, and recursion theory. Research in mathematical logic commonly addresses the mathematical properties of formal ...
. Since women were not allowed to graduate from Johns Hopkins University at that time, Ladd was refused a PhD in mathematics and logic, although she was the first woman to complete all the university's requirements for a PhD. Completing the work for a PhD in mathematics and logic at Johns Hoplkins University gave her the tools and the legitimacy she needed, as a woman taking up scientific work. The university eventually officially awarded her a PhD during its 50th-anniversary celebrations in 1926 (44 years after she had earned it) when she was seventy-eight.[
In 1893 she sought a teaching position at Johns Hopkins University but was denied. Despite this setback, she remained persistent and determined.] Laurel Furumoto, in his work discussing the sociopolitical environment of the time, notes that Ladd's "inability to secure a regular academic position was a predictable consequence, in that time period, of her decision to marry."[Furumoto, L. (1994). Christine Ladd-Franklin's color theory: Strategy for claiming scientific authority? In. Adler, H.E. & Rieber, R.W. (Eds.) Aspects of the history of psychology in America: 1892-1992 (pp. 91-100). New York: The New York Academy of Sciences.] Eleven years later, in 1904, she was at last given permission to teach one class per year. For the next five years her position at Johns Hopkins University had to be approved and renewed on a yearly basis. Women who were able to obtain academic positions in universities at this time often chose these positions despite their lack of compensation. Ladd was no different. Many of the teaching positions that she held were on a volunteer basis, creating substantial financial strain on her and her family. Yet, it is evident that Ladd placed a high value on her ability to earn the academic affiliations necessary to become a successful contributor to her field.
Personal life and philosophy
After marriage to Fabian Franklin
Fabian Franklin (1853–1939) was a Hungarian-born American engineer, mathematician and journalist, husband of Christine Ladd-Franklin.
Life and work
The Franklin family (his parents were born in Poland) migrated from Hungary to Philadelphia ...
on August 24, 1882, she adopted the name Christine Ladd-Franklin. The couple had two children, one of whom died in infancy. The other, Margaret Ladd-Franklin, became a prominent member in the women's suffrage movement
Women's suffrage is the women's rights, right of women to Suffrage, vote in elections. Beginning in the start of the 18th century, some people sought to change voting laws to allow women to vote. Liberal political parties would go on to gran ...
.[ Ladd-Franklin often wrote of the injustice she observed in the oppression of the female sex. In one such journal entry while at Vassar College she describes her disappointment with the views in society about and among women, stating, "I so despise the idea that woman are not as competent to take care of themselves as men, that they cannot decide for themselves when to go to bed and when to get up, how much exercise to take, how much to pray and go to church. Still my greatest objection is to the class of girls who come here and to the social and political atmosphere of the place ... I know of but one girl who declares herself for the rights of women" (September 22, 1866).] In another journal entry she writes about the lack of recognition of women who have earned advanced educational degrees, "That is the case with our clever girls -- they go to Germany and get the parchments, beautifully signed and sealed, that proclaim them to be doctors of philosophy, but no further consequences follow. They have nothing but the empty satisfaction of exhibiting their 'tickets.
She died on March 5, 1930 in New York, New York.[
]
Major contributions and achievements
After leaving Hopkins, Ladd-Franklin worked with German psychologist G. E. Müller, where she carried out experimental work on vision. Although women in academic settings and laboratories were viewed as equally unwelcome as in the United States, she managed to secure a position. Ladd-Franklin was also able to work in the laboratory of Hermann von Helmholtz
Hermann Ludwig Ferdinand von Helmholtz (31 August 1821 – 8 September 1894) was a German physicist and physician who made significant contributions in several scientific fields, particularly hydrodynamic stability. The Helmholtz Association, ...
, where she attended his lectures on theory of color vision. After attending these lectures, Ladd-Franklin developed her own theory of color vision.[ In 1929 she published ''Color and Color Theories''.
]
Ladd-Franklin's theory of color vision
One of the major contributions that Ladd-Franklin made to psychology was her theory of color vision, which was based on evolution. Ladd-Franklin noted that: "some animals are color blind and assumed that achromatic vision appeared first in evolution and color vision came later." She assumed further that the human eye carries fragments of its earlier evolutionary development. She observed that the most highly evolved part of the eye is the fovea
Fovea () (Latin for "pit"; plural foveae ) is a term in anatomy. It refers to a pit or depression in a structure.
Human anatomy
*Fovea centralis of the retina
* Fovea buccalis or Dimple
* Fovea of the femoral head
* Trochlear fovea of the fr ...
, where, at least in daylight, visual acuity and color sensitivity are greatest. Ladd-Franklin assumed that peripheral vision (provided by the rods of the retina
The retina (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then ...
) was more primitive than foveal vision (provided by the cones of the retina) because night vision and movement detection are crucial for survival."
Stages of color vision
Ladd-Franklin concluded that color vision evolved in three stages: achromatic vision (black and white), blue-yellow sensitivity and red-green sensitivity.[ Since red-green sensitivity was the last to evolve it explains why many people suffer from ]red-green color blindness
Color blindness or color vision deficiency (CVD) is the decreased ability to see color or differences in color. It can impair tasks such as selecting ripe fruit, choosing clothing, and reading traffic lights. Color blindness may make some aca ...
. The next one that affects a small population is blue-yellow color blindness. Since achromatic vision was the first to evolve it explains why the majority of the population are not affected by black-white color blindness.[
]
Mathematics and logic
Ladd-Franklin was the first woman to have a published paper in the ''Analyst''. She was also the first woman to receive a PhD in mathematics and logic.[Peirce's Ph.D. student Christine Ladd-Franklin found the truth table in ''Tractatus Logico-Philosophicus'' Proposition 5.101, 40 years earlier than Wittgenstein]
Christine Ladd (1881), "On the Algebra of Logic", p.62
''Studies in Logic'', C. S. Peirce ed., 1883 The majority of her publications were based on visual processes and logic. Her views on logic influenced Charles S. Peirce's logic and she was highly praised by Arthur Prior
Arthur Norman Prior (4 December 1914 – 6 October 1969), usually cited as A. N. Prior, was a New Zealand–born logician and philosopher. Prior (1957) founded tense logic, now also known as temporal logic, and made important contribution ...
.[
]
Professional involvement
Ladd-Franklin was among the first women to be inducted into the American Psychological Association
The American Psychological Association (APA) is the largest scientific and professional organization of psychologists in the United States, with over 133,000 members, including scientists, educators, clinicians, consultants, and students. It ha ...
in December 1893. From 1894 to 1925, Ladd-Franklin presented ten papers at APA meetings.[ She was also one of the first female members of the ]Optical Society of America
Optica (formerly known as The Optical Society (OSA) and before that as the Optical Society of America) is a professional society of individuals and companies with an interest in optics and photonics. It publishes journals and organizes conference ...
in 1919. During their meetings she presented six papers and two exhibits.[ Ladd-Franklin was included in the '']Who's Who in America
Marquis Who's Who ( or ) is an American publisher of a number of directories containing short biographies. The books usually are entitled ''Who's Who in...'' followed by some subject, such as ''Who's Who in America'', ''Who's Who of American Wome ...
'' during 1901-1902 and 1914-1915. Ladd-Franklin remained a member of both scientific societies until her death.[ She was also a prominent member of the women's rights movement.
In 1948, ]Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, (18 May 1872 – 2 February 1970) was a British mathematician, philosopher, logician, and public intellectual. He had a considerable influence on mathematics, logic, set theory, linguistics, ...
wrote: "I once received a letter from an eminent logician, Mrs. Christine Ladd-Franklin, saying that she was a solipsist
Solipsism (; ) is the philosophical idea that only one's mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure; the external world and other minds cannot be known ...
, and was surprised that there were no others. Coming from a logician and a solipsist, her surprise surprised me."[Russell, B. (1948). Human Knowledge: Its Scope and Limits. New York: Simon and Schuster. p. 180.]
Published works
* "Quaternions", '' The Analyst'' v. 4, n. 6, pp. 172–4 (Nov 1877). Google Books ''The Analyst'
p. 172
i
n. 6 (November)
i
v. 4 (1877)
Also JSTO
"Quaternions" first page
(Several journals have been called "''The Analyst''". See The Analyst (disambiguation). Internet searches for ''The Analyst'', the one which became ''The Annals of Mathematics'', should use the search phrase "The Analyst" mathematics
, otherwise ''The Analyst'' about chemistry will dominate search results.)
* "On the Algebra of Logic" in '' Studies in Logic'', C. S. Peirce, ed., pp. 17–71, 1883. Google Book
Eprint
Internet Archiv
Eprint
* "A Method for the Experimental Determination of the Horopter" in the ''American Journal of Psychology'', v. 1, n. 1 pp. 99–111, November 1887. JSTO
* "On Some Characteristics of Symbolic Logic" in the ''American Journal of Psychology'', v. 2, n. 4, pp. 543–567, August 1889. Google Book
Eprint
Internet Archiv
Eprint
* "Epistemology for the logician" in ''Verhandlungen des III. Internationalen Kongresses fur Philosophie.'', pp. 64–670, 1908. Also separately as an offprint.
* "Charles Peirce at the Johns Hopkins", ''The Journal of Philosophy, Psychology, and Scientific Methods'' v. 13, n. 26, 715–723, December 1916. Google Book
Eprint (badly done)
an
seek the text
* "The Reddish Blue Arcs and the Reddish Blue Glow of the Retina; an Emanation from Stimulated Nerve Fibre." in ''VIIIth International Congress of Psychology: Proceedings and Papers'', 1926.
* ''Colour and Colour Theories'', Routledge, 320 pages, 1929.
See also
*Timeline of women in science
This is a timeline of women in science, spanning from ancient history up to the 21st century. While the timeline primarily focuses on women involved with natural sciences such as astronomy, biology, chemistry and physics, it also includes women f ...
References
References
*
*
* Hurvich, Dorothea Jameson (1975), "Ladd-Franklin, Christine" ''Notable American Women'', Vol. 2, 4th ed., The Belknap Press of Harvard University Press.
* Nubiola, Jaime and Cobo, Jesús (2000), "The Spanish Mathematician Ventura Reyes Prósper and His Connections with Charles S. Peirce and Christine Ladd-Franklin", Arisbe, Lubbock, TX
Eprint
Includes an English translation "Christine Ladd Franklin: American Mathematician and her influence on symbolic logic" of the paper "Cristina Ladd Franklin. Matemática americana y su influencia en la lógica simbólica" by Prósper published in ''El Progreso Matemático'', 12 (1891), 297–300.
* Spillman, Scott, "Institutional Limits: Christine Ladd-Franklin, Fellowships, and American Women's Academic Careers, 1880–1920," ''History of Education Quarterly'' 52 (May 2012), 196–221.
*''Notable Women in Mathematics, a Biographical Dictionary'', edited by Charlene Morrow and Teri Perl, Greenwood Press, 1998. pp 107–113
* Biography on p. 338-346 of th
Supplementary Material
a
AMS
/ref>
External links
The Christine Ladd-Franklin Diary 1866–1873
*''Vaughn, Kelli'' (2010)
Profile of Christine Ladd-Franklin
. In A. Rutherford (Ed.), ''Psychology's Feminist Voices Multimedia Internet Archive''
*Christine Ladd Franklin's 1921 letter to ''The New York Times
''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid ...
'' about the lack of women in the American Academy of Arts and Letters
The American Academy of Arts and Letters is a 300-member honor society whose goal is to "foster, assist, and sustain excellence" in American literature, music, and art. Its fixed number membership is elected for lifetime appointments. Its headqu ...
{{DEFAULTSORT:Ladd-Franklin, Christine
American psychologists
American women psychologists
American logicians
American women mathematicians
19th-century American mathematicians
20th-century American mathematicians
19th-century American women scientists
Vassar College alumni
Johns Hopkins University alumni
Charles Sanders Peirce
1847 births
1930 deaths
20th-century women mathematicians