Christine Ladd-Franklin

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

Early life and education Christine Ladd, sometimes known by the nickname "Kitty", 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. Before Ladd turned five, her mother had taken her to a lecture given by Elizabeth Oakes Smith, a well-known proponent of women's rights. Additionally, her father was a graduate professor who was supportive of his eldest daughter's education.

In 1865, Ladd graduated from Wesleyan Academy and pursued further education at Vassar College, supported by her family.

In the fall of 1866, Ladd enrolled in Vassar College, financed by a loan from her aunt Juliet Niles, Mitchell was also a suffragette 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. Because women in nineteenth-century America were prohibited from working in physics laboratories, Ladd chose to study mathematics. When they did realize her gender, the board tried to revoke the offer, but Sylvester insisted that Ladd should be his student, and so she was. (44 years after she had earned it) when she was seventy-eight. 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. 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 of pneumonia

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. 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. During their meetings, she presented six papers and two exhibits.

Ladd-Franklin was included in the Who's Who in America during 1901–1902 and 1914–1915. Ladd-Franklin remained a member of both scientific societies until her death.

A limerick for Dr Christine Ladd-Franklin, 'The Lonely Solipsist', by William Grey. Dr Christine remarked, "It is queer, When the solipsist truth is so clear, I'm alone in my view That the theory is true Since there's no other solipsist here!"

Published works "Quaternions", The Analyst v. 4, n. 6, pp. 172–4 (Nov 1877). Google Books The Analyst p. 172 in n. 6 (November) in v. 4 (1877). Also JSTOR "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 Books Eprint. Internet Archive 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. JSTOR . "On Some Characteristics of Symbolic Logic" in the American Journal of Psychology, v. 2, n. 4, pp. 543–567, August 1889. Google Books Eprint. Internet Archive 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 Books Eprint (badly done) and 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.