Mary Calkins, American philosopher and psychologist (d. 1930)
Mary Whiton Calkins (; 30 March 1863 – 26 February 1930) was an American philosopher and psychologist, whose work informed theory and research of memory, dreams and the self. In 1903, Calkins was the twelfth in a listing of fifty psychologists with the most merit, chosen by her peers. Calkins was refused a Ph.D. by Harvard University because of her gender.

Calkins is a key figure in the history of women psychologists. At Wellesley College, Calkins established the first psychological laboratory for women. She was the first woman to complete the requirements for a doctoral degree in psychology with the unanimous support of the Harvard University psychology faculty, although the University refused to bestow it on the grounds that Harvard did not accept women. She later became president of the American Psychological Association and the American Philosophical Association, and was the first woman to be president of both.

She taught psychology and philosophy at Wellesley College for four decades, and conducted research there and at Harvard University for the majority of that time.