Introduction to Astronomy

After the Sun, the Moon comes to the testimony of things. For to many, even of the common people, it is not in doubt that the approaches of the Moon to the Sun and its recessions—that is, its risings and settings—and the increases and decreases of the air and seas in animals, grasses, and metals, are accompanied by movements of qualities and quantities. This is subject to the increases and decreases of moisture in the menstrua of animals and the daily fluctuations of the sea, or the approaches and recessions of the lunation through weeks. Many also obtain through numerous experiments that different times are affected by various qualities according to the different mansions of the Moon; as from this one, the ancients understood clouds; from that one, rains; and other things of this kind.

After the Sun and the Moon, certain effects of all the stars are then established. Besides the fact that they are not as widely approved as the virtue of the luminaries, it is by no means unknown even to the common people that the qualities of the times are altered between the increases and decreases of the stars through a certain participation with the Sun and the Moon. If this participation were not the cause of these movements, summer would never be hotter than summer, nor winter colder than winter. It is certain, therefore, that in every nation, through all climates, the generations and corruptions of things are moved by the alterations of the seasons. Moreover, the cause of these alterations is the Sun and the Moon, and the aids of the stars. First, indeed, from the experiments of the long lives and vigilant investigations of our predecessors, reserved until the memory of posterity. Second, from those things which were established by relating kindred things to those that were less evident, thereby leading the ingenuity forward. Since, therefore, ingenuity more readily grants a reason, it seems to be asserted that the causes of experiments are not inept in the investigation of things. For every craft has in its own kind the faith of experiments, from things passed to those that follow. Thus, indeed, the farmer, the pastor, and the sailor, in their own office, predict convenient or inconvenient hours from the positions of certain stars. The farmer, indeed, for sowing and grafting; the pastor for the mating of herds and flocks, for stable conceptions and healthy births. The sailor, nonetheless, foresees friendly and hostile winds from the experiments of the past. For all these, the experiments of the Sun and Moon and the courses of the stars make faith through the movements of the elements and the alterations of the seasons. In grafting, the farmer foresees from the hour and time of grafting among the types of trees: these to increase, those to accelerate fruits, others to indulge in fruits, others in one way or another. From which, if we seek a place of argument, the use of experiments pretends nothing that is ambitious. This is akin to the predictions of midwives, to which experiments give faith. For the experienced person first foresees whether she is pregnant. Secondly, they discern the sex; then, from the firstborn—which they call virginal births—they foresee whether the mother will give birth again, counting the future births themselves. Having had a suspicion of pregnancy, when it is to be discerned by experiment, they mark the nipples. If they appear suffused and clasped, and her...