PREFACE.

...principles original: "principibus"; completing the word from the previous page. deduced a priori original: "a priori"; reasoning based on theoretical deduction or definitions rather than observation or experience., you will find those to be the very things into which all Euclidean Referring to Euclid of Alexandria, the ancient Greek mathematician; his "elements" of geometry were considered the pinnacle of logical certainty. elements are resolved, and from which those same elements—and indeed the whole of Mathematics original: "Mathesis universa"—derive all their clarity. Furthermore, the other philosophical disciplines expect their principles from Ontology original: "Ontologia"; the branch of metaphysics that studies the nature of being and existence. no less than mathematics does; without these principles, they are deprived of that evidence which alone is sufficient for firm conviction. It can hardly be expressed how much assistance these ontological notions—which may be drawn from the present work—provide to those who are meditating or teaching; for this reason, I have been accustomed to call them by the name of guiding notions original: "notionum directricium"; fundamental concepts that serve as a compass for the mind, directing it toward discovering further truths.. Moreover, many more things remain which could be added to these, but they must be deduced from the things we have already handed down. Therefore, for those who make our ideas familiar to themselves, it will be by no means difficult to progress to further matters once they have clearly perceived the laws of the scientific method original: "methodi scientificæ"; Wolff's rigorous approach to philosophy, which applied the demonstrative logic of mathematics to all fields of knowledge. and have learned to apply them in practice. The philosophical works that follow will speak clearly of the fertility of these ontological principles, since the things to be demonstrated in those works are resolved into these very same principles.