Sor Juana Inés de la Cruz (1648-1695) is a legend in her native Mexico and elsewhere in Latin America. She is esteemed for the artistic and intellectual quality of her wide-ranging poetry, plays, and prose writings. She is renowned for her defense of the right of women to study, to publish their scholarship, and to teach, all controversial claims in her era of Catholic patriarchy. In recent decades, Sor Juana's work has finally become known to English-speaking audiences. To date, however, no thorough analysis of her conception of education has been published in any field of educational research. In this essay, David Hansen addresses that oversight by examining several of her key works in order to illuminate her philosophy of education. For Sor Juana, education is an endlessly demanding ethical undertaking, in the sense of making serious claims on the person's commitments and sense of direction. At the same time, education positions the person to articulate serious, public demands for justice in society.