I might indeed ask at the outset how such complete ignorance of scholasticism were possible: an ignorance not of its manifold varieties and the tangled forest of its distinctions--that would be comprehensible: but of no less a matter than the fundamental criterion of its theory of knowledge, the starting-point of modern thought and as such, it would seem, inevitably familiar to every student of the elements of philosophy. But since it is always useful to suspect oneself of ignorance, or even to believe oneself more ignorant than one really is, I will make so far as concerns myself a voluntary display of humility. I find it less easy, I confess, to extend the accusation of ignorance to all who, like myself, have failed to run Vico's criterion to earth in the scholastic lumber-room: Jacobi for instance, who on reading it as expressed in the _De antiquissima,_ sees in it the first manifestation of Kantianism and absolute idealism:[2] or the Catholic theologian Baader, who finds its later development in Schelling's philosophy of identity:[3] or the learned and subtle Spanish Thomist, Jaime Balmes, who treats it as a unique idea and attacks it from the scholastic point of view:[4] or the equally learned Catholic Bertini, who accepts and develops Jacobi's observation:[5] or the eminent historian of philosophy Wilhelm Windelband, who, while unacquainted with Vico's doctrines, on coming across indications of a similar thought in Sanchez's _Quod nihil scitur_ was greatly struck by it and endorsed its value by the assertion that it was to bear fruit at a later date and in the hands of a greater philosopher, Immanuel Kant:[6] or again the specialist in the history of scholasticism, Karl Werner, the author of a careful monograph on Vico,[7] who nowhere notices the alleged scholastic character of Vico's theory of knowledge. Scholasticism must indeed be a difficult and mysterious doctrine, if it is inaccessible to all these students, qualified and bound though they are to understand it. But we cannot pause on the threshold to speculate: we must plunge straight into the argument. In what part of scholasticism can we find Vico's criterion converting knowledge with creation? The Thomistic saying, "truth and reality are convertible," _ens et verum convertuntur,_ has been quoted:[8] but quotations of this kind are perhaps more calculated to confuse by words than to convince by facts. The same value attaches to the statement that Vico himself confessed the scholastic origin of his principle, since the very first chapter of the _De antiquissima_ begins with the words "in Latin, the truth and the fact reciprocate, or, as the scholastic mob says, convert," _"Latinis verum et factum reciprocantur, seu, ut scholarum vulgus loquitur, convertuntur."_ Here it is perfectly clear to any one on a moment's thought that Vico, Latinist as he was, meant simply to substitute the Ciceronian "_reciprocari_" for the barbarous "_converti._"