Hugh MacColl and Christine Ladd-Franklin: 1877–1909

An outsider in the logic community, Hugh MacColl (1837–1909), achieved recognition of his work in logic belatedly in the nineteenth and early twentieth centuries. Together with George Boole, Augustus De Morgan, William Stanley Jevons, Charles S. Peirce, Ernst Schröder, John Venn, Christine Ladd-Franklin and others, MacColl considered logic as a calculus represented by the algebra of logic. In an article published in 1889 in The American Journal of Psychology, Ladd-Franklin wrote, “Nothing is stranger, in the recent history of Logic in England, than the non-recognition, which has befallen the writings of this author….it seems incredible that English logicians should not have seen that the entire task accomplished by Boole has been accomplished by Maccoll [sic.] with far greater conciseness, simplicity and elegance.” Examining some of her work and the work of her contemporaries, I explore the possible reasons she had for holding this opinion.