Christine Ladd-Franklin

http://vcencyclopedia.vassar.edu/alumni/christine-ladd-franklin.html

http://en.wikipedia.org/wiki/Christine_Ladd-Franklin

http://www.feministvoices.com/christine-ladd-franklin/

Christine Ladd-Franklin (December 1, 1847 – March 5, 1930) was the first American woman psychologist, logician, and mathematician.

Early Life and Early Education

Christine Ladd-Franklin was born as Christine Ladd on December 1, 1847 in Windsor, Connecticut to Eliphalet Ladd, a merchant, and Augusta 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. Following the death of her mother in spring 1860 to pneumonia, Ladd went to live with her paternal grandmother in Portsmouth, New Hampshire where she attended school.

After the death of her mother Ladd’s father remarried in 1862 and produced her half-sister, Katherine (born 1862) and a half-brother, George (born 1867). Ladd was a precocious child who sought to find “a mean to continue her education beyond secondary school.”. Ladd’s wish was granted when her father enrolled her in a two years program at a coeducational Welshing academy in Wilbraham, Massachusetts where she took the same courses that prepared boys in furthering their education to colleges such as Harvard. In 1865 Christine Ladd as valedictorian graduated from Welshing Academy.

In the fall of 1866 Ladd enrolled in Vassar College with a loan provided by her late mother’s sister. She only studied at Vassar until the end of the spring term due to financial issues. During the time that she was not attending college Ladd worked as a public school teacher until her aunt aid allowed her to reenter Vassar and graduate in 1869. At Vassar Ladd was interested in physics but knew that the field was not open to women so she studied mathematics.

Early Career Development

After graduating, Ladd taught science and mathematics at secondary level in Washington, Pennsylvania. During this time, Ladd contributed seventy-seven mathematical problems and solutions to the Educational Times of London published. She also published six items in The Analyst: A Journal of Pure and Applied Mathematics and three in the American Journal of Mathematics.

Graduate Education

In 1878, Ladd was accepted into Johns Hopkins University with the help of James J. Sylvester, an English mathematician who remembered some of Ladd’s earlier works in London Educational Times. At this time Hopkins did not approve of coeducation so Ladd was only allowed in classes taught by Sylvester. After displaying exceptional work in Sylvester’s courses, Ladd was allowed to take other courses with different professors. Even though she was awarded a stipend, she was known as a fellow student. During 1879–1880, Ladd took classes taught by Charles Sanders Peirce who has been called the first American experimental psychologist. She wrote a dissertation "On the Algebra of Logic" with Peirce as the thesis advisor. The dissertation was published in Studies in Logic (Peirce, ed.) in 1883. Due to her studies with Peirce, Ladd became the first American woman to be involved in psychology, mathematics and logic. Since women were not allowed to graduate at Hopkins, Ladd was refused a Ph.D. in Mathematics and Logic, although she was the first woman to complete all the requirements for a PhD at Hopkins. However, Hopkins officially granted her a Ph.D. in February 22, 1926 (44 years after she had earned it) at the age of seventy eight.

Soon after completing graduate work at Johns Hopkins, she married Fabian Franklin (a fellow graduate student who received his Ph.D. in mathematics), hence she became Christine Ladd-Franklin. Ladd-Franklin had two children, one of whom died in infancy, the other Margaret Ladd Franklin, who became a prominent member in the women’s suffrage movement.

Major Contributions and Achievements

After leaving Hopkins, Ladd-Franklin worked with a prominent German psychologist G. E. Müller, where she carried out experimental work in vision. In addition to working with Müller, Ladd-Franklin was able to work in the laboratory of Hermann von Helmholtz, 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 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 vestiges of its earlier evolutionary development. She observed that the most highly evolved part of the eye is the fovea, 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) 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; the first Achromatic vision (black and white), blue-yellow sensitivity and finally red-green sensitivity. Since red-green sensitivity was the last to evolve it explains why many people suffer from red-green color blindness. 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 Ph.D. in mathematics and logic. 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 Prior.

Professional involvements

Ladd-Franklin was among the first women to be inducted into the American Psychological Association in December 1893. From 1894-1925, Ladd-Franklin presented ten papers at APA meetings. She was also one of the first female members of the Optical Society of America (OSA) in 1919. During the OSA meetings she presented six papers and two exhibits. She was also a prominent member of the women’s rights movement. Ladd-Franklin was included in the Who’s Who in America during 1901-1902 and 1914-1915. Ladd-Franklin remained a member of APA and OSA until her death on March 5, 1930 in New York, New York.

In 1948, Bertrand Russell wrote: "I once received a letter from an eminent logician, Mrs. Christine Ladd-Franklin, saying that she was a solipsist, and was surprised that there were no others. Coming from a logician and a solipsist, her surprise surprised me." (Russell, p. 180).

Published works

http://en.wikipedia.org/wiki/Christine_Ladd-Franklin#Published_works