Problem: I know that the answer to the question "Who wrote a book first?" is in "In the early 11th century, the Muslim physicist Ibn al-Haytham (Alhacen or Alhazen) discussed space perception and its epistemological implications in his Book of Optics (1021), he also rejected Aristotle's definition of topos (Physics IV) by way of geometric demonstrations and defined place as a mathematical spatial extension. His experimental proof of the intromission model of vision led to changes in the understanding of the visual perception of space, contrary to the previous emission theory of vision supported by Euclid and Ptolemy. In "tying the visual perception of space to prior bodily experience, Alhacen unequivocally rejected the intuitiveness of spatial perception and, therefore, the autonomy of vision. Without tangible notions of distance and size for correlation, sight can tell us next to nothing about such things."". Can you tell me what it is?

A: Aristotle

Problem: I know that the answer to the question "What is not actually the background of the name Vergilius?" is in "In the Late Empire and Middle Ages Vergilius was spelled Virgilius. Two explanations are commonly given for this alteration. One deduces a false etymology associated with the word virgo ("maiden" in Latin) due to Virgil's excessive, "maiden"-like modesty. Alternatively, some argue that Vergilius was altered to Virgilius by analogy with the Latin virga ("wand") due to the magical or prophetic powers attributed to Virgil in the Middle Ages (this explanation is found in only a handful of manuscripts, however, and was probably not widespread). In Norman schools (following the French practice), the habit was to anglicize Latin names by dropping their Latin endings, hence Virgil. In the 19th century, some German-trained classicists in the United States suggested modification to Vergil, as it is closer to his original name, and is also the traditional German spelling.[citation needed] Modern usage permits both, though the Oxford guide to style recommends Vergilius to avoid confusion with the 8th-century grammarian Virgilius Maro Grammaticus. Some post-Renaissance writers liked to affect the sobriquet "The Swan of Mantua".[citation needed]". Can you tell me what it is?

A: the word virgo

Problem: I know that the answer to the question "How does it influence the world's economy?" is in "London is a leading global city, with strengths in the arts, commerce, education, entertainment, fashion, finance, healthcare, media, professional services, research and development, tourism, and transport all contributing to its prominence. It is one of the world's leading financial centres and has the fifth-or sixth-largest metropolitan area GDP in the world depending on measurement.[note 3] London is a world cultural capital. It is the world's most-visited city as measured by international arrivals and has the world's largest city airport system measured by passenger traffic. London is one of the world's leading investment destinations, hosting more international retailers and ultra high-net-worth individuals than any other city. London's 43 universities form the largest concentration of higher education institutes in Europe, and a 2014 report placed it first in the world university rankings. According to the report London also ranks first in the world in software, multimedia development and design, and shares first position in technology readiness. In 2012, London became the first city to host the modern Summer Olympic Games three times.". Can you tell me what it is?

A: has the fifth-or sixth-largest metropolitan area GDP in the world depending on measurement

Problem: I know that the answer to the question "What does a cosmonaut navigate?" is in "By 1959, American observers believed that the Soviet Union would be the first to get a human into space, because of the time needed to prepare for Mercury's first launch. On April 12, 1961, the USSR surprised the world again by launching Yuri Gagarin into a single orbit around the Earth in a craft they called Vostok 1. They dubbed Gagarin the first cosmonaut, roughly translated from Russian and Greek as "sailor of the universe". Although he had the ability to take over manual control of his spacecraft in an emergency by opening an envelope he had in the cabin that contained a code that could be typed into the computer, it was flown in an automatic mode as a precaution; medical science at that time did not know what would happen to a human in the weightlessness of space. Vostok 1 orbited the Earth for 108 minutes and made its reentry over the Soviet Union, with Gagarin ejecting from the spacecraft at 7,000 meters (23,000 ft), and landing by parachute. The Federation Aeronautique Internationale (International Federation of Aeronautics) credited Gagarin with the world's first human space flight, although their qualifying rules for aeronautical records at the time required pilots to take off and land with their craft. For this reason, the Soviet Union omitted from their FAI submission the fact that Gagarin did not land with his capsule. When the FAI filing for Gherman Titov's second Vostok flight in August 1961 disclosed the ejection landing technique, the FAI committee decided to investigate, and concluded that the technological accomplishment of human spaceflight lay in the safe launch, orbiting, and return, rather than the manner of landing, and so revised their rules accordingly, keeping Gagarin's and Titov's records intact.". Can you tell me what it is?

A:
universe