Theories of the Medicean Planets Deduced from Physical Causes

These fibers, when they contract, pull the part attached to them, and in this way motion is created. No part endowed with motion exists that lacks these aforementioned fibers. In the same way, we see that nutrition occurs through countless tiny channels original: "canaliculis", referring to the microscopic vessels or pores believed to transport nutrients in the 17th century, such as veins, arteries, and lacteal and lymphatic vessels, as well as the roots of plants. We see that the preservation of life in animals depends on that principle of motion within the heart. Not a single animal will be found that lacks a heart, liver, or spleen, or a brain and other vital organs. Although some variation in the position, shape, and size of these organs occurs frequently, it is never possible to find any animal deprived of these principal members and organs. This clearly shows that nature neither knows how to, nor is able to, produce the functions of living things without these instruments and without those common principles by which the instruments themselves operate. From this it is deduced that if an animal were brought to us from a very remote climate, never before seen by our eyes, we could nevertheless predict—not just as a probability, but as a certainty—that it would have a perpetually beating heart, muscles serving its motion, a liver, a brain, and other parts.

Therefore, since both the Huygenian Moon The moon of Saturn, now called Titan, discovered by Christiaan Huygens in 1655 around Saturn, and the Medicean stars around Jupiter, revolve from west to east; and just as our Moon revolves around the Earth, and the primary planets the major planets orbiting the Sun, as opposed to "secondary planets" or moons revolve around the Sun from west to east; and since the Medicean stars complete their revolution in a shorter time the closer they are to Jupiter; and just as the primary planets finish theirs sooner the closer they are to the Sun; and since all planets, both primary and secondary, are carried around the significant globes of the world—namely the Sun, Saturn, Jupiter, and the Earth—it must indeed be established that the motions of such wandering stars are completed according to a universal rule common to all. For it is certain and established, as we have shown, that nature does not perform and operate similar effects and functions with different organs, but with the same ones. This is necessary...

tan- catchword: "tantum" (so much/only)