PREFACE.

...is able to weigh original: "perpendere valet"; this completes a thought from the previous page, likely suggesting that anyone who examines the author's reasons can judge for themselves.; such a person will sufficiently understand that our own work has been of more benefit to us in understanding the ideas of others, than the ideas of others have been in discovering our own. Furthermore, by this very fact, it becomes clear how our writings shed light on things said more obscurely by others, so that they may be understood most fully. This holds true not only in First Philosophy original: "Philosophia prima"; another name for metaphysics, the branch of philosophy dealing with the first principles of things, including abstract concepts like being, knowing, and substance., but in all other forms of knowledge. We have provided examples of this elsewhere, such as in the original: "oratione de Sinarum philosophia practica"; refers to the author's controversial 1721 lecture at Halle, where he argued that Chinese Confucian ethics were valid based on human reason alone. Discourse on the Practical Philosophy of the Chinese and in our Leisure Hours original: "Horis nostris subsecivis"; the title of a collection of academic and philosophical essays by the author.. We shall provide more in the future within these very pages, as well as in other philosophical works; and those who make our ideas familiar to themselves through untiring study will experience this for themselves.

If there should be any to whom the ontological principles original: "principia ontologica"; the fundamental rules or laws governing the nature of being and existence. proposed here seem sterile or of little importance, I would wish them to consider that the utility of principles does not appear until they have been applied to demonstrating other things. Thus, those who judge their use hasten to a conclusion before they have been concerned with applying them, or before any occasion for applying them has presented itself. The Euclidean Elements original: "elementa Euclidea"; the foundational geometry textbook by Euclid of Alexandria. seem much more "sterile," such that no one ignorant of the rest of Mathematics original: "Matheseos"; specifically the broad science of quantity and measurement as understood in the 18th century. could guess their utility. But once you have advanced into the other parts of Mathematics, you discover so great a use for them that you would never have allowed yourself to be persuaded of it by anyone else. Some principles concerning quantity, which here from the notions