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urges that they should be cast aside. Good God, how great is the sharpness of intellect in this man! He has crept into and penetrated the very marrow of the teachings of such great men, after so many centuries have passed, just to observe their mistakes, so that he might finally purge the world of errors that have remained hidden for so long. Or perhaps the speculation of the ancient world was so crude that, before this time, it was unable to look into the errors of the Ancients in Astronomy and Music.
But let us now return to his own self-love original: "philautiam," from the Greek philautia, meaning excessive conceit or vanity. and his vast inspection of nature. We find two impressions of this matter in this context; the first is: I draw the material of my harmony from the nature of things, and establish it from its very foundations. The second: I proceed in a natural order, so that all things are corrected according to the laws of nature, and confusion is avoided; and thus I do not even apply established rules to the opinions of the Ancients, except where no confusion follows. Since he boasts that in his books on the Harmony of the World he has opened the sanctuary of nature, and has found in it the true and natural harmony of things above all others—extracting it from the very womb and foundations of nature—it will certainly be right to leaf through his books. From there, we may gather whether such a revelation of nature was actually made there or not; and similarly, whether he proceeds by a method and order so natural as to correct the "confusions" of other Authors.
He distributes his first book into geometric definitions and propositions concerning multifaceted surfaces with equal sides, which he calls "regular." With these, he makes a more ready entry into the composition of his "regular solids," from whose proportions he seems to elicit his harmony. These plane figures, which he treats in this book, he makes either perfectly regular (in which all sides and angles are equal); and these he divides again into "primary and radical" figures, or "augmented" ones—those which exceed their sides when the non-adjacent sides of some radical figure are continued until they meet. These he calls "stars" This refers to Kepler's discovery of star polygons, now known as Kepler-Poinsot polyhedra.. Or he calls them less perfect or "semi-regular," which vary in their angles even if their sides are equal, such as Rhombs. Here he reviews many degrees of knowledge pertaining to angular figures.
He also has many propositions pertaining to the sides of the Square, the Octagon, the Sixteen-sided figure, the Triangle, the Hexagon, the Heptagon, the Dodecagon, and its star; the Decagon with its star, the Pentagon with its star, and other such regular angular figures. Similarly, he treats the circle and its various sections, and here he ends that book. In it, we find nothing pertaining to the true Harmony of the world’s nature; rather, he makes a certain Geometric comparison between one angular figure and another. If this indeed be harmony, it is certainly "analogical" and named so by resemblance, and not in truth—or rather, it is a Mathematical and imaginary Harmony, not a Natural one, which consists of the benevolent interactions and perfectly disposed passions of the world-soul term: "anima mundana" (World Soul). In Fludd's philosophy, this is the spiritual force that animates the universe. with its material substance. It was never the intention of the Philosophers that natural harmony should consist of Geometric dimensions, since the acting soul does not admit of a visible measurement.
In the second book, he treats the "congruence" term: "congruentia" (congruence). The way shapes fit together to fill a space without gaps. of figures, which he applies either to a plane—making this either "perfect," when the individual angles of multiple surfaces meet at a point so that no gap is left and all that meet are similar (this being a congruence of figures of the same species); or "imperfect," where there is a similar mixture of figures of different species. Or he applies it to solids. This is "most perfect" when the angles of figures (whether regular or semi-regular) of the same species meet; or "perfect but of a lower degree" when figures fitting at the angles are of different species; or it is an "imperfect congruence" when, other things remaining the same, a larger figure is found no more than once or twice. In planes, therefore, he says the Triangle fits with the square, and likewise the pentagon with its star; Hexagons also fit together; so too the Octagon and Decagon with their stars, and the Dodecagon with its star, etc. In semi-regular bodies, he describes congruence in Propositions 27 and 28. Regarding the most perfectly regular ones, he treats them in Propositions 25 and 26. In Proposition 25, he describes those five "most perfect and regular bodies" These are the five Platonic Solids: the tetrahedron, cube, octahedron, dodecahedron, and icosahedron., about whose properties the Pythagoreans, Plato, and Proclus sang so much. And here he believes the force of the world’s harmony consists; and so this is the force of his Book 2. Here we see that this harmony of his, which he calls the "congruence of figures," is entirely imaginary; he interprets Plato’s intention through a mystical allusion to those five regular bodies.
In the third book, he treats first the discovery of Music, Pythagorean numbers, and the Pythagorean Tetractys The "Tetractys" is a triangular figure consisting of ten points, a sacred symbol for Pythagoreans representing the organization of space and the universe. through definitions, axioms, and many propositions for inquiring into the causes of the "delays" likely referring to rhythmic durations or rests of musical consonances. Similarly, he treats the discovery of harmonic proportions from various sections of a string. He also treats harmonic means, the origin of suitable intervals (where he strives to refute the opinions of the Ancients), the division of consonant intervals into suitable ones, the types of Song (Soft and Hard note: "Molle & Durum." These terms refer to the hexachord system; "Molle" (soft) used B-flat, while "Durum" (hard) used B-natural, roughly correlating to minor and major qualities.), the number of intervals in the Octave consonance original: "Diapason", the division of the Monochord, the composition of systems, "adulterine" meaning false or impure consonances, naturally suitable Song, the modes of melodies, and other such things. Thus, in this book, we find nothing except mere "artificial music" gathered from the books of many Ancient Authors; we find nothing of his own here, except that he delights in contradicting the Ancients' reasons for the discovery of intervals.
In these first three books, therefore, the Author has neither drawn the material of his harmony from the nature of things, nor established it from its foundations, as he promised; nor has he proceeded naturally so that anything might be corrected by the laws of nature to avoid confusion. Let us proceed, therefore, to his fourth book, in which, before he arrives at the full flow of his subject,