Open Access

Marco Toste

• Invincible ignorance is defined as the state in which one cannot overcome his ignorance, despite one’s utmost diligence, and hence cannot be blamed for the acts resulting from that circumstance. It is particularly relevant with regard to law and principles that one is bound to know. The main problem with the admission that such a state may occur results from the difficulty of assessing the subjective element present in such a state: How can we know that one applied his diligence to the utmost extent? This notion emerged in the 12th century. But while medieval theologians elaborated such a notion, they nonetheless stressed that in reality no one could be guiltlessly ignorant of natural and divine law. The arrival of the Spaniards to the Americas triggered the awareness that entire nations could, in fact, be invincibly ignorant of Christianity. The Spanish theologians then started to use this notion, admitting the existence of invincible ignorance of some principles of divine and natural law. Their argumentative strategy rested on emphasising the subjective element of invincible ignorance. In this article, I examine Vitoria’s Relectio de Indis against the medieval doctrinal background. I also analyse Vitoria’s, Domingo de Soto’s and Juan Gil de Nava’s unedited lectures on Aquinas’s Summa theologiae as well as the works by Matías de Paz, Juan López de Palacios Rubios, Juan de Celaya and Bartolomé de Las Casas.