Marietta Kies distinguished herself as one of the first American women to earn a Ph.D. in philosophy. She was also one of the first women to become a professional academic philosopher in the United States, teaching at the college level at four institutions. She was a member of the idealist movement in American philosophy, which imported into the United States the basic principles of German thought, particularly that of Georg Wilhelm Friedrich Hegel and his contemporaries, along with their progressive educational ideas. While Kies's female colleagues in the idealist movement focused almost solely on pedagogy or on feminist theory in their published work, she discussed matters unrelated to education or to women's issues and developed a political philosophy in which altruism is a central concept.

Kies was born on 31 December 1853 in Killingly, a small town in the northeast corner of Connecticut, to William Knight and Miranda Young...