In 1665, a plague broke out in London, the universities closed, and students returned home. One of the students stayed at home for two years, during which time he developed calculus and discovered some optical principles and gravity

In 1665, a plague broke out in London, the universities closed, and students returned home. One of the students stayed at home for two years, during which time he developed calculus and discovered some optical principles and gravity, and this person was named Newton.

When the Black Death broke out in Europe, a group of young people in Italy took refuge in the city and gathered together every day to talk about yellow paragraphs for a total of ten days. Later, someone collected these passages and published a book that became a world famous book called "Ten Days Talk".