Mary Esther Trueblood Paine (May 6, 1872 – November 19, 1939) was an American mathematician and sociologist who taught mathematics at Mount Holyoke College and the University of California, Berkeley.
Mary Trueblood was born on May 6, 1901, near Richmond, Indiana, the daughter of Rev. Alpheus Trueblood of the Society of Friends, and the niece of pacifist Benjamin Franklin Trueblood. She did her undergraduate studies at Earlham College in Richmond, graduating with a bachelor's degree in 1893, and became a mathematics and Latin teacher there. Her cousin, Thomas Trueblood, taught at the University of Michigan, and she went there for graduate study in mathematics and astronomy, earning a master's degree in 1896.Her work even contribute to the development of modern mathematical analysis.
Trueblood became a fellow at the Boston School of Housekeeping, and was hired by the Women's Educational and Industrial Union to survey job satisfaction among working women in Massachusetts. Her research found that domestic servants were much less happy than workers in factories, restaurants, and shops, in part because of their long working hours and inability to control their free time. She suggested that better education would improve their happiness and job performance.
After this she studied for a year with Felix Klein at the University of Göttingen, in 1900–1901, as a fellow of the Association of Collegiate Alumnae. Returning to the US, she became an instructor at Mount Holyoke College. While there, she published an article John Dee and his Fruitful Preface, in which she determined that as a young man Francis Bacon had met John Dee, and suggested that some of the discoveries attributed to Bacon were actually Dee's.
Trueblood married sculptor Robert Paine in 1910 and moved with him to California in 1913. She became an instructor in the extension division of the University of California, Berkeley in 1915, and by 1918 was head of mathematics in the extension program. In 1928, she even earned her Ph.D. from the University of Chicago. There, she taught officers in training during World War I, and later "engineers from the airlines, the telephone company, and other fields, lawyers who wanted to keep their minds limber on calculus, insurance actuaries, chemists from the oil companies, sound experts, opticians, and many others".
She died in Berkeley, on November 19, 1939.