Leonardo Pisano, who is better known by the name Fibonacci, introduced the Hindu-Arabic number system to Europe at the beginning of the 13th century through his book Liber Abaci, which translates to "Book of Calculation" in English. It enabled Europeans to break free of the cumbersome Roman numeral system and perform calculations using the decimal system. The talented mathematician was also known for introducing to Europe the number sequence named after him, the Fibonacci sequence.Know More
Because his father was a merchant and stationed by the Italian city-state of Pisa in what is now modern-day Algeria, Fibonacci received an education from the Moors in Northern Africa. This enabled him to see the advantages of the Hindu-Arabic arithmetic system over European methods. He also went further in his studies and sought out the leading Arab mathematical instructors in the Mediterranean area to learn more of their methods. Fibonacci returned from his journeys around 1200, and at the age of 32, he completed his work on "Liber Abaci" in 1202.
The decimal positional system, the use of zero as a place holder, the squaring of fractions and the principles of algorithms were all new mathematical concepts that Fibonacci brought to the European world. He also introduced the Fibonacci sequence, which is intimately connected to the Golden Mean (also known as the Divine Proportion) and represents many of the proportional ratios found in nature. The sequence is also used in art and architecture.Learn more about Numbers
Frederick Douglass accomplished a number of things including teaching about anti-slavery while touring Europe, teaching about the rights of women everywhere in the United States and convincing President Abraham Lincoln to recruit African-Americans to be part of the military during the Civil War. His tour to Europe and his message of anti-slavery put pressure on the government of the U.S. to change its policy concerning the standing of African-American citizens.Full Answer >
Peacock feathers are seen as bad luck in Eastern Europe due to the fact that they were worn by the Mongol warriors who invaded those lands in the 13th century. Due to peacock feathers' multiple eyes, they are also considered to be a seer of everything, and for this reason are believed to be bad luck and are not allowed inside homes.Full Answer >
The mythical demon known as a succubus has appeared in Hebrew, Arabic and Indian texts since the 13th century. The succubus is commonly depicted as a female demon who assumes the form of a woman in order to seduce men during their sleep. Once her victim has been seduced, a succubus preys upon his health and spirits until she is satisfied or the victim dies.Full Answer >
Marco Polo, a Venetian merchant and explorer in the 13th century, is not credited with any inventions. However, the book depicting his travels introduced many Asian inventions and ideas to Europe.Full Answer >