万事无不可以人力为之者。15世纪,人们知道地球是圆的,但还不知道它有多大、大海有多宽。25岁的哥伦布站在葡萄牙的海岸上想:只要这茫茫大海比马可·波罗跋涉过的陆地窄一些,我就有必要搞一艘船到那盛产黄金和香料的东方大陆去发掘。通过阅读托勒密的《地理学》,他得知欧亚大陆 Everything can be human. In the 15th century, people knew that the earth was round, but they did not know how big it was and how wide the sea was. Columbus, 25, stands on the coast of Portugal and thinks that as long as this sea is narrower than Marco Polo’s land, I need to find a boat to explore the eastern continent where gold and spices are abundant. After reading Ptolemy’s Geography, he learned about Eurasia