DOCTA IGNORANTIA. - An expression derived from letter 130 of St. Augustine to Froba concerning the «quid oremus sicut oportet nescimus»; (Rom. 8, 26), who adds: «est ergo in nobis quaedam ut ita dicam d. i. sed docta spiritu Dei qui adiuvat infirmitatem nostram» (15, 28; PL 33, col. 505). The formula owes its fame above all to the work of Nicolò da Cusa entitled De d. i. (1440).
Taking up the ideas of pseudo-Dionigi and of the theologians of the Middle Ages concerning negative theology, and affirming the impotence of reason before the knowledge of intellectual truth, Nicolò endeavours to establish the claims of a higher, intuitive knowledge, freed from the laws of Aristotelian logic, and especially from the principle of non-contradiction, the only knowledge that enables us to attain God; all creatures that owe their existence to Him tend to draw near to Him, and man in particular, the microcosm that sums up within itself the whole of creation; this is possible only through Jesus Christ and the Church. Nicolò thus wished to free the science of his time from the yoke of nominalist Aristotelianism; but he was violently attacked, and not without reason, because his manner of expression seemed, at first sight, inspired by pantheistic doctrines. Yet the underlying substance of his thought is thoroughly orthodox, although he does not assign reason its due role in knowledge.