During this period of just over a hundred years there was more creativity and realism than ever before and it appeared in the publications of three innovators. These recorded the observations of Leonardo da Vinci (1519), and the calculations by Copernicus (1540) and Galileo (1632).
The first was by one of the greatest of all observers, Leonardo da Vinci (1452-1519), with his many drawings of living things. Much of what he saw and interpreted holds good today, the animals and plants varying slightly over space and short intervals of time, their environment changing, the earth’s landmasses moving about the globe. During the early Renaissance, science and art were intermingled, with artists like da Vinci making observational drawings of anatomy and nature, and many of the diagrams of his skilled medical dissections are still well-known today. He also went on to make controlled experiments, involving water pressure, relativity movements and aerodynamics.
da Vinci’s helicopter, The Annunciation 1475-1480, human embryo and foetus 1510:
The processes he began were much like the holistic approaches to science that are becoming popular again today. For example, at one stage he intimated that biological structures were part of some self-organised complex system. Da Vinci died at peace with himself and with these amazingly advanced thoughts, as well as with the God of his early sixteenth century Florence.
This was also the time when the Polish astronomer Nicolaus Copernicus (1473-1543) was gathering data from his astronomical observations and calculating that the earth was not at the centre of the universe. It wasn’t too hard for the church in Krakow to adjust to his work, mainly because they liked the man for who he was, and didn’t fully understand the implications of his work.
In 1543 Copernicus presented his major theory: On the Revolutions of the Celestial Spheres and it had seven major conclusions:
“1. There is no one center of all the celestial circles or spheres.
2. The center of the earth is not the center of the universe, but only of gravity and of the lunar sphere.
3. All the spheres revolve about the sun as their mid-point, and therefore the sun is the center of the universe.
4. The ratio of the earth’s distance from the sun to the height of the firmament (outermost celestial sphere containing the stars) is so much smaller than the ratio of the earth’s radius to its distance from the sun that the distance from the earth to the sun is imperceptible in comparison with the height of the firmament.
5. Whatever motion appears in the firmament arises not from any motion of the firmament, but from the earth’s motion. The earth together with its circumjacent elements performs a complete rotation on its fixed poles in a daily motion, while the firmament and highest heaven abide unchanged.
6. What appear to us as motions of the sun arise not from its motion but from the motion of the earth and our sphere, with which we revolve about the sun like any other planet. The earth has, then, more than one motion.
7. The apparent retrograde and direct motion of the planets arises not from their motion but from the earth’s. The motion of the earth alone, therefore, suffices to explain so many apparent inequalities in the heavens.”
A hundred years later, the technical improvements in optical instruments enabled Galilei Galileo (1564-1642) to discover much more evidence for those same ideas, and he did run into difficulty with the church in Rome. With great publicity he defended the views by writing his most controversial work, Dialogue Concerning the Two Chief World Systems. It was published in 1632 and it caused him to be arrested and tried before the Inquisition. That powerful group of churchmen found him “vehemently suspect of heresy” and he was forced to recant.
He spent the rest of his life under house arrest.