The Example of Jansenism
The meaning in a case of historical significance can be explained by a reference to the condemnation by Pope Innocent X of five propositions taken from the posthumous book of Jansenius, entitled Augustinus.
Could the pope define that Jansenius really was the author of the book entitled Augustinus? No, he may speak of it as the work of Jansenius, because, in general repute, at least, it was regarded as the work of Jansenius. The precise authorship of a book is called a personal fact.
The question turned on the doctrine of the book. The Jansenists admitted that the doctrine enunciated in the condemned propositions was heretical; but they maintained that the condemned doctrine was not taught in the Augustinus. This brings us to what are called "particular facts of doctrine". Thus it is a fact (in this sense) that God exists, and that there are Three Persons in God; here the same thing is fact and dogma. The Jansenists admitted that the pope is competent to deal with particular facts of doctrine, but not to determine the meaning of a book. The controversy was then carried to the meaning of the book.
The pope cannot define the purely internal, subjective, perhaps singular meaning, which an author might attach to his words. But the pope, in certain cases, can determine the meaning of a book judged by the general laws of interpretation. And when a book or propositions from a book are condemned, "in the sense of the author", they are condemned in the sense in which the book or propositions would be understood when interpreted according to the ordinary laws of language. The same formula may be condemned in one author and not in another, because, interpreted by the context and general argument of the author, it may be unorthodox in one case and not in another. In the strict sense, therefore, a dogmatic fact may be defined as "the orthodox or heterodox meaning of a book or proposition"; or as a "fact that is so connected with dogma that a knowledge of the fact is necessary for teaching and conserving sound doctrine".
That a book contains unorthodox doctrine, conveys that a certain doctrine is unorthodox; here we have close connection between fact and dogma.
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