The article by Alan Lightman is about asking questions and finding answers rather than simply accepting was it already known as fact.
             The article by Lightman is about finally realizing that we have been accepting of many things without question. Lightman uses himself as an example, that due to his profession as an astrophysicist, he has been taught not to take things for granted, yet, that he in fact just realized that he did not know for certain whether the earth was flat or round.
             To further emphasize his point, Lightman uses Aristotle as a prime example of someone who is not just accepting of the facts. Aristotle firmly believed that the Earth was round and therefore set out to proof his belief. Therefore, he used science, mathematics, and astronomy to proof his belief. The article further explains Aristotles' proofs to his belief that the Earth was round.
             Aristotle used Astronomy in his first proof to show that the Earth was round. His proof stated that the shadow of the Earth during a lunar eclipse was always curved, a segment of a circle, therefore, the Earth must be round. He further explained that if the Earth was any other shape than round, the shadow it casts wouldn't be spherical.
             In his second proof, Aristotle again used Astronomy to proof his belief. His second proof used the rise and setting of stars. According to this proof, the stars rise and set sooner for people in the East than in the West. If the Earth were flat from east to west, stars would rise as soon for Occidentals as for Orientals. Again, proving that the Earth was round.
             Aristotle's third proof was theoretical. Again using mathematics and science to back up his belief, Aristotle stated that "even if the Earth had been formed from smaller pieces at some time in the past (or could have been so formed), its pieces would fall toward a common center, thus making a sphere," In mathematics, a sphere is
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