Previously Unpublished Works, Fascicle 16

[The human mind] cannot investigate those things by its own power, as Aristotle teaches, and I have demonstrated this in my Metaphysics. Similarly, no other things that I have listed (or elsewhere named) can be taught by any specific science, because they are common and general to all particular sciences.
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For this reason, they are reserved for the "common science" Bacon refers to "common science" (scientia communis) as a foundational branch of knowledge, often identified with metaphysics, that provides the basic rules and definitions used by all other specific subjects., whose proper role is to shape and form all other sciences and to show how they ought to be constructed (or otherwise known) and taught. And because a human being errs in many ways, and there are certain universal causes of human errors that greatly hinder us in every science, life, and business, this universal science precedes them so that they may be avoided in all particular sciences. Therefore, desiring to treat mathematics within the roots of metaphysics—just as I did with logic, which mathematics follows immediately—I wish, as I ought, to refrain for the most part from the demonstration of those things which I have already verified in that other common science. However, I will recount many things verified there that are useful for mathematics by way of narrative description, as is suitable for mathematics. Sometimes, though rarely, I will bring forward certain metaphysical proofs in specific cases when there is a great necessity, so that I do not propose anything with too much novelty without its proper reason, especially when the opposite is commonly accepted as true. In this way, I will effectively take up the office of the metaphysician, as Aristotle did at the beginning of his Sophistical Refutations original: "Elenchorum" and Physics and elsewhere, either by proving that the subject of a science exists, or by proving a principle or some other necessary cause, according to what the matter to be explained requires. It is not surprising that many of the same things are touched upon in different sciences, for all sciences are connected to one another, and it is certain that they agree on many points. I have shown this with certainty in my works on metaphysics, and there is no need to doubt this in any way.

Second part of the first chapter.

I HAVE INDEED DECLARED in the Metaphysics that "mathematics" is spoken of in two ways. One is a part of philosophy, and the other is counted among magical and erroneous follies. For that which is erroneous is neither a part of philosophy nor of any wisdom.

Line 11: The editor uses "precedes" (precurrit), while the manuscript reads "runs through" (percurrit).