PREFACE.

so that there was almost no use for either the former referring to the obscure definitions mentioned on the previous page or the latter referring to the ambiguous rules or "canons". To this was added the abuse of these terms in the other parts of Philosophy, and even in what they call the Higher Faculties Higher Faculties In the traditional university system, these were the professional schools of Theology, Law, and Medicine, which sat "above" the Faculty of Philosophy (Arts).; from which arose that perverse opinion, as if Ontology were a barbarian philosophical lexicon original: Lexicon barbarum philosophicum, in which philosophical terms are explained that we could for the most part safely do without. Nor did it contribute a little to the contempt of First Philosophy that Descartes original: Cartesius, despairing of defining ontological terms which we cannot do without, declared that they need no definition, because in his opinion they belong to the number of those things which are better understood than defined.

As soon as I had proposed to myself to make philosophy both certain and useful to the human race, and for that purpose inquired into the reason for the evidence of Euclidean referring to Euclid of Alexandria, the ancient Greek mathematician whose "Elements" set the standard for logical proof demonstrations, I discovered that, besides the form which I recently outlined in my Logic, it mathematical evidence depends on ontological notions. For the first principles which Euclid uses are nominal definitions nominal definitions original: definitiones nominales; definitions that explain the meaning of a name or word, rather than explaining the actual essence or possibility of the thing itself., in which no truth resides by itself, and axioms self-evident truths that require no proof, most of which are ontological propositions. And so I understood that Mathematics original: Mathesin owes all its certainty to First Philosophy, from which it draws its first principles. When, next, [I arrived at] theorems in philosophy to be demonstrated...