Then during the Abbasid era, House of Wisdom was established in Baghdad, where scholars from different parts of the world translated books into Arabic, Greek, Persian and Indian languages. ... He published his book Book of Optics, where he stated his famous vision theory that every point on the object being viewed emits rays of light that travel to the viewer's eye. ... It includes scientific theories and information. ... Moreover, they corrected Greek theories and added new information. ... They corrected theories and added assured ideas and knowledge. ...

• Word Count: 989
• Approx Pages: 4
• Grade Level: High School

This suggested to him that there must be something fatally incorrect about the Aristotelian/Ptolemaic universal theory. ... Suddenly, scientists were faced with mathematical calculations, as opposed to simply fervent speculation, in support of the heliocentric theory of the universe. ... Another factor is that the Catholic Church continued to allow him to teach Copernicanism as a mathematical theory, their opposition was solely to Galileo expressing his deduction that the Copernican theory was in fact true (Catholic Encyclopedia). ...

• Word Count: 4135
• Approx Pages: 17
• Grade Level: High School