# Christine Ladd-Franklin

Christine Ladd-Franklin (December 1, 1847 – March 5, 1930) was an American psychologist, logician, mathematician, and pioneering activist for equal educational and career opportunities for women. She is known for her theory of evolution of color vision.

## Quotes

* I shall adopt the convention by which particular propositions are taken as implying the existence of their subjects, and universal propositions as not implying the existence of their subjects. Mr. Jevons would infer that the two propositions The sea-serpent is not found in the water, The sea-serpent is not found out of the water, are contradictory; bur Mr. McColl, Mr. Venn, and Mr. Peirce would infer that the sea-serpent does not exist. With this convention, contradiction can never exist between universal propositions nor between particular propositions taken by themselves. A universal proportion can be contradicted only by a particular proposition, and a particular only by a universal. The above premises are inconsistent with The sea-serpent has (at least once) has been found. With this convention, hypothetical and categorical propositions receive the same formal treatment. If a, then b = all a is b = a implies b. (Peirce.)
** "On the Algebra of Logic by Christine Ladd". Studies in Logic. Boston: Little, Brown, and Company. 1883. pp. 17–71. (quote from p. 23; edited by Charles Sanders Peirce)
* What gives significance and value to truths is that they permit of interesting predictions.
** "Epistemology for the Logician by Christine Ladd-Franklin". Bericht über den III. Internationalen Kongress für Philosophie zu Heidelberg, September 1908. Heidelberg: Carl Winter's Universitätsbuchhandlung. 1909. pp. 664–670. (quote on p. 669; edited by Prof. Dr. Theodor Elsenhans)
* Peirce … was of the brooding type. He sat when he addressed his handful of students (who turned out afterwards, however, to be a not unimportant handful) and he had all the air, as has been noted by Professor Jastrow, of the typical philosopher who is engaged, at the moment, in bringing fresh truth by divination out of some inexhaustible well. He got his effect not by anything that could be called an inspiring personality, in the usual sense of the term, but rather by creating the impression that we had before us a profound, original, dispassionate and impassioned seeker of truth. No effort was made to create a connected and not inconsistent whole out of the matter of each lecture. In fact, so devious and unpredictable was his course that he once, to the delight of his students, proposed at the end of his lecture, that we should form (for greater freedom of discussion) a Metaphysical Club, though he had begun the lecture by defining metaphysics to be the “science of unclear thinking.”
** (December 1916)"Charles S. Peirce at the Johns Hopkins". The Journal of Philosophy, Psychology and Scientific Methods 13 (26): 715–722. DOI:10.2307/2012321. (quote from pp. 717–718; edited by Frederick James Eugene Woodbridge and Wendell Ter Brush)

## Quotes about Christine Ladd-Franklin

* In their attempts to get around these artificial barriers and inconsistencies, early women scientists developed a great many strategies. These tended to be of two sorts. One was the idealistic, liberal-to-radical, and often confrontational strategy of demanding that society reject all stereotypes and work for the feminist goal of full equality. This involved writing angry letters and otherwise documenting the "unfairness" of the unequal opportunities open to men and women. The most prominent and successful strategist of this school was Christine Ladd-Franklin, a Vassar College graduate of the 1860s, would-be physicist turned mathematician, psychologist, and logician, who for fifty years, worked shrewdly and tirelessly for educated women. Her greatest triumph was in opening graduate schools to women in the 1890s, and thus allowing women to earn the same doctorates as men.
** Margaret W. Rossiter, "Introduction". Women Scientists in America: Volume One. Struggles and Strategies to 1940. John Hopkins University Press. 1982. p. xvii. ISBN 0-8018-2509-1.

## External links

* Encyclopedic article on Christine Ladd-Franklin on Wikipedia
* Media related to Christine Ladd-Franklin on Wikimedia Commons
* Christine Ladd-Franklin '1869. Vassar Encyclopedia.