The main ideas we associate with the Enlightenment. It was believed that during the Enlightenment, human reasoning could be used to discover truths about the world, religion, and politics and could be used to make the lives of people better. Another important idea was skepticism about received wisdom. Everything had to be tested and proven correct. Other Enlightenment ideas were religious tolerance and the idea that people should be free from coercion in their personal lives and consciences.

Leonhard Euler was a Swiss physicist, astronomer, logician, engineer, geographer, and mathematician. According to Wikipedia, he also “founded the studies of graph theory and topology and made pioneering and influential discoveries in many other branches of mathematics such as analytic number theory, complex analysis, and infinitesimal calculus.” He was alive from 1707 to 1783, so he was alive during the Scientific Revolution. According to csmonitor.com, “Euler was the first to introduce the notation for a function f(x). He also popularized the use of the Greek letter π to denote the ratio of a circle’s circumference to its diameter. Euler also made contributions in the fields of number theory, graph theory, logic, and applied mathematics.” Also, he was extremely good at math. He could do calculations in his head that does not seem possible to some people.

The Ptolemaic-Aristotelian view of the universe. According to Vassar College, “In this cosmology, the earth does not revolve around anything else or rotate around its own axis. It is surrounded by ten concentric spheres made of a perfectly transparent substance known as “quintessence.” These spheres revolve around the earth, carrying the other celestial bodies.” So, this is not what we associate with the universe today. In today’s world, we associate our universe (galaxy) as the sun in the center with eight planets and their moons revolving on their axis’s around the sun.