The Book of the Four Parts of Ptolemy, that is, of the four treatises: on the rooted discernment by the stars concerning the future events of construction and destruction happening in this world. In the first treatise of this work, there are 24 chapters. It begins:

Chapter One: On the collection of the understanding of the science of the judgments of the stars.

Preface.

From the books of St. Geneviève. 1753.

Of original: "Rerum". The letters following the decorative 'R' are partially obscured by the woodcut frame those things in which the prognostic science of the stars consists, we ought to consider that there are two great and principal parts. Of these, one—which precedes and is the more powerful—is the science that demonstrates the configurations of the Sun and Moon, as well as the five wandering stars The "wandering stars" are the planets known to the ancient world: Mercury, Venus, Mars, Jupiter, and Saturn.; it is manifest that these occur because of their movements and the relationship of one to another and of them to the Earth. The other part is the science by which are explained the changes and works which happen and are completed because of the natural figures of their circuits upon those things which they surround. But since of the two aforementioned, the first is indeed a science in itself and unmixed with the other, it is necessary that the investigator of science should seek it out and learn it for its own sake and receive its fruit here, even if he does not add the second of the sciences. Since in truth it is manifest that this is so, and having already completed for you the first science in itself in a volume Ptolemy refers here to his earlier work, the Almagest, which dealt with mathematical astronomy. in which we proceeded reasonably according to our ability: in this book we shall explain the second science, which is by no means explainable in itself, as physical reason demands. It is necessary, however, for its investigator to follow this intention: that he proceed in it by a straight path and a truthful way. Yet he should not wish to liken the manner of arriving at this science to the manner by which one arrives at the other, which is always of one and the same mode. For he will set aside and deny this science if he compares them. For the brief delay of the accidents in the matter in which this science is occupied is the occasion of the change of this second science. For this matter never perseveres in the same state; therefore, the foreknowledge of this science is attained with difficulty. For this reason, however, it should be set aside by no one because of laziness, since he should strive to know from it what is possible to be known. It is indeed plain that that which surrounds us is the primary occasion of the accidents and changes occurring in this world. Since, however, it is the habit of many to despise difficult things for investigation, some—out of blindness of mind and ignorance—were setting aside the first part of the science by accusing it, while others did so to the second. The occasion distracting them to these things is perhaps this: they are either like those who, because they cannot know something due to its excessive difficulty, think that others can by no means know it; or perhaps they repudiate it even though they are able to know it, because it easily flows away from the memory. For these reasons, therefore, despising this science, they reputed it as nothing. We, however, before we manifest the particulars of this science, will briefly strive to prove what is in it, and what can be known of the science of prognostication, and what fruit follows; and from these two we will begin to explain how much it is that we can reach from this science.

Chapter Two: How we can arrive at the prognostic science of the judgments of the stars, and how much it is that can be known from it.

It is clear that some labor exists in the matter which, reaching even to earthly things, compels them to change—indeed, it forces them—and those same things likewise naturally receive changeability from...

LIBRARY OF ST. GENEVIEVE