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Eratosthenes was the man to first accurately estimate the circumference of the earth. Pythagoras had first theorised in approximately 500 BC that the earth was a sphere
Eratosthenes' most famous discovery is his accurate prediction of the earths circumference. He did this by comparing altitudes of the mid-day sun at two places a known North-South distance apart. His calculation was remarkably accurate. He was also the first to calculate the tilt of the earth's axis (again with remarkable accuracy). Additionally, he may have accurately calculated the distance of the earth to the sun. and invented the leap year. He created the first map of the world, incorporating parallels and meridians based on the available geographic knowledge of his era.
Contrary to common misconception, the medieval church did not teach that the earth was flat. Thomas Aquinas introduced Aristotelian thought into medieval church teaching. Writing in the fourth century BC, Aristotle clearly taught that the earth was spherical. As indicated above, In the early second century BC, Eratosthenes accurately measured the circumference of the spherical earth. Claudius Ptolemy's Almagest, from the early second century AD, provided a useful model for calculating the positions of heavenly bodies. While this model was geocentric, it did not promote a flat earth, but instead was based upon a spherical earth. The works of Aristotle, Eratosthenes, and Ptolemy were all widely available and discussed in the late medieval period, and continued to be through the transition to the Renaissance. Given the clear record of history, why is it so commonly believed today that most people, and especially the church, thought that the earth was flat?
This misconception is easily traced to the writings of two late nineteenth-century skeptics, John William Draper and Andrew Dickson White, who invented the conflict thesis. The conflict thesis holds that religion in general, and Christianity in particular, held back progress. The contention of the conflict thesis was that medieval Europe was gripped with superstition that prevented intellectual advancement, and it was only after man's reason reasserted itself during the Renaissance that man slowly became unshackled from religious dogma, bringing about the Enlightenment. It is true that four centuries ago the Roman Catholic Church opposed Galileo's teaching of the heliocentric theory. According to the conflict thesis, it was the alleged geocentric teaching of the Bible that caused the Roman Catholic Church to oppose Galileo.
However, the historical record demonstrates that it was the teachings of Aristotle and Ptolemy that played the major role in that conflict That is, the Galileo affair was a battle between two scientific theories—geocentrism and heliocentrism—with the Bible playing a very minor role. Hence, the conflict thesis reinterpreted the Galileo affair into something that it was not.
The promoters of the conflict thesis also retold the story of Christopher Columbus. Most people today persist in the belief that at the time of Columbus, nearly everyone thought that the earth was flat. According to the story, Columbus was one of the few people who thought the earth was spherical, and he understood that on a spherical earth one could sail westward from Europe to reach India and China. Supposedly, Columbus had to argue against strong objections coming from those who thought that the earth was flat to get support for his expedition. Finally, according to the story, Columbus managed to complete a voyage to the New World, and when he returned to Europe, people realized that Columbus was right—the world was round and not flat. Really? How did sailing from Europe to the Caribbean and back to Europe prove that the world was spherical? It didn't. The truth is that no one told Columbus he could not reach the Far East by sailing west. Everyone knew that it was possible, because everyone knew that the earth was spherical. The problem was that the earth was very large. Most people understood that the distance westward from Europe to the Far East was far greater than going eastward (a look at any globe proves this). The question was not how possible it was to reach Asia by going westward, but rather how feasible it was. The belief was that the ocean between Europe and Asia was vast, with little or no land in between. At the time of Columbus, voyages over open water were very risky, and ships rarely sailed more than three days out of the sight of land. A voyage westward across the ocean to Asia would have required months, with no opportunity for resupply or rescue along the way if problems developed.
The facts of history refute the commonly held story about Christopher Columbus. Much of the work supporting a flat earth today uncritically repeats and builds upon this false view. The flat earth movement began in the mid-nineteenth century, the same time that the conflict thesis was being developed. While the skeptics were ridiculing the Bible for allegedly teaching that the earth is flat, early flat-earthers foolishly accepted this false claim. Undoubtedly, the recent surge of interest in the flat earth among Christians has been fueled by the (false) belief that the Bible teaches that the earth is flat. Those who have enlisted in the flat-earth movement of late apparently are ignorant of the fact that those who promoted the conflict thesis made the same arguments to discredit the Bible. This could be ironic, or perhaps it is not. It is possible that certain people promoting the flat-earth today are doing so to discredit the Bible and Christianity all over again. If so, then Christians who have been misled into believing that the earth is flat have foolishly fallen into the trap.
Apologies if you took it in that manner it was never meant that way nor did I IMHO imply that you were intellectually impaired.attitude addressing everyone else as an idiot. .
Dave, I think that it's actually the reverse. Columbus, et. al., thought that the Earth's was much smaller thus Asia could be reached by sailing westward. Thus INDIANS for the natives Columbus encountered. That the Earth was large enough for another entire continent to block his route was inconceivable.as they thought the globe was much larger than it actually is. I
Sooo....put the lid on tighter next time, so all the carbonation doesn't escape!I think that I should avoid this thread as it is leaving me flat.
Just to be clear, did they mean the Caribbean or India? How big exactly did they expect earth to be?GrauGeist said:Columbus (and his contemporaries) knew that the "Indies" could be reached by sailing westward. BUT, they assumed that the voyage would take months to accomplish, as they thought the globe was much larger than it actually is.
Wait... according to the definition of Stadion, that's 185-192 meters and that would mean thatmikewint said:Dave, The idea of sailing westward to India dates back to the early Romans. The Roman writer Strabo, not long after Erathosthenes and Posidonius, reported their results and noted:
"if of the more recent measurements of the Earth, the one which makes the Earth smallest in circumference be introduced--I mean that of Posidonius who estimates its circumference at about 180,000 stadia, then. . . "
and he continues:
"Posidonius suspects that the length of the inhabited world, about 70,000 stadia, is half the entire circle on which it had been taken, so that if you sail from the west in a straight course, you will reach India within 70,000 stadia. "
Notice that Strabo--for unclear reasons--reduced the 250,000 Stadia of Eratosthenes to 180,000, and then stated that half of that distance came to just 70,000 stadia. Handling his numbers in that loose fashion, he could argue that India was not far to the west.
Why weren't we taught this stuff in school?All these results were known to the panel of experts which King Ferdinand appointed to examine the proposal made by Columbus. They turned Columbus down, because using the original value by Eratosthenes, they calculated how far India was to the west of Spain, and concluded that the distance was far too great.
Just to be clear, did they mean the Caribbean or India?
Why weren't we taught this stuff in school?
lol Terry!No Dave, the plot flattens ............. and if the earth is flat, how come there are 'Round the World Yachtsmen' ?