考满分 toefl

1 .<-NARRATOR:->Listen to part of a lecture in a history of science class.

旁白：听下面一段科学史的课堂讲解。

1 .<-FEMALE PROFESSOR:->Ok, we've been talking about how throughout history, it was often difficult for people to give up ideas,which had long been taken for granted as scientific "truths," even if those ideas were false.

教授：好了，我们一直在讨论一个贯穿历史性的问题，人们往往很难放弃那些长期以来被认为是科学“真理”的想法，即使这些想法是错误的。

2 .In astronomy, for example, the distinction between the solar system and the universe wasn't clear until modern times.

比如在天文学上来讲，人们对太阳系与宇宙的区别的认知直到现代才逐渐清晰起来。

3 .The ancient Greeks believed that what we call the solar system was in fact the entire universe... and that the universe was geocentric.

古希腊人认为我们所谓的太阳系就是整个宇宙，宇宙是以地球为中心的。

1 .Geocentric" means Earth centered, so the geocentric view holds that the Sun, the planets, and the stars all revolve around the Earth, which is stationary，Of course, we now know that the planets, including Earth, revolve around the Sun, and that the solar system is only a tiny part of the universe.

顾名思义，地心说意味着以地球为中心，地心的观点认为太阳、行星及恒星都围绕地球来转，地球是静止不动的，当然了，我们现在都知道所有的行星，包括地球，都是围绕太阳来转的，而且太阳系也仅仅是宇宙的一小部分而已。

1 .So, why did the ancient Greeks believe that the Earth was the center of the universe?

那么，古希腊人又为什么认为地球是宇宙的中心呢？

2 .Well, it made sense to them—observations of the sky made it appear as if the Sun, the Moon, and the stars all revolved around the Earth every day, while the Earth itself stayed in one place.

其实他们这种想法也不无道理，当我们仰望天空的时候，给我们的视觉效果的确是太阳、月亮及星星，都每天围绕地球来转的，而且地球是原地不动的。

3 .And this view was also supported by their philosophical and religious beliefs about the origin and structure of the universe.

而且他们的哲学和宗教信仰都在支撑着这种对宇宙的起源和构架的认知。

4 .It was presented in the works of well-known Greek philosophers as early as the fourth century B.C.E.

这在公元前四世纪的希腊著名哲学家们的作品中都有体现。

5 .And the geocentric theory continued to prevail in Western thought for almost 2,000 years, until the seventeenth century.

而地心说的理论在西方思想中持续了近 2000 年，直到 17 世纪。

1 .Now what's especially interesting is that when astronomical observations were made that seemed to be inconsistent with the geocentric view, the ancient Greeks did not really consider alternate theories.

极其有趣的是当天文观察的发现与地心说有所出入的时候，古希腊人却没有真正的去考虑过其他的理论。

2 .It was so intuitive, so sensible that the Earth was the center of the universe ，that astronomers found ways to explain those seemingly inconsistent phenomena within the geocentric view.

天文学家们认为地球是宇宙的中心这种想法是那么的根深蒂固，以至于当他们发现与地心论不符的现象时，也会想办法找理由去解释。

1 .For example, Greek astronomers made excellent, very accurate observations of the movements of the planets.

比如说，希腊天文学家对行星的运动进行了非常精准的观测。

2 .But the observations revealed a bit of a problem.

但是观察中却显示出了一个小问题。

3 .The geocentric theory said that the planets would move around Earth in one direction.

地心说的理论是所有的行星都围绕地球朝着一个方向转动。

4 .However, astronomers noticed that at times, several planets seemed to stop moving in one direction and start moving backward in their orbits around Earth.

然而，天文学家们却发现，一些行星有时看上去似乎停止向一个方向移动，而且是绕着地球沿着轨道朝相反的方向转动。

5 .And they came up with the theory that these planets themselves moved in smaller circles, called epicycles, as they traveled around the Earth.

这时他们就得出一个理论，即这些行星在绕地球转动的同时也在沿着更小的圈转动，被称为“本轮”。

6 .Here's a picture of what they imagined.

这幅图就是他们想象中的画面。

1 .You see how this epicycle theory could account for the seeming backward motion of a planet.

你可以看到这个本轮理论表面上来讲就解释了行星倒行的这种现象了。

2 .Of course, today we know that this appearance of backward motion is caused by the fact that Earth as well as other planets all move in their own orbits around the Sun, and the relative movements of the planets with respect to each other can get quite complex.

当然了，现在我们知道这种倒行的现象其实是地球及其他行星在围绕太阳在自己轨道上公转时显现出来的，而行星间相对的运动也是非常复杂的。

1 .However, there were a few astronomers in Greece and other places ,who didn't agree with the geocentric view, for example, a-a Greek astronomer who lived in the third century B.C.E..

然而，希腊及其他地区也有几位天文学家，不相信地心说的，比如说公元前三世纪的一位希腊天文学家。

2 .He proposed the theory that our planetary system might be heliocentric.

他提出了我们的行星系统的日心说。

3 .His name was Aristarchus.

他就是阿利斯塔克斯。

1 ."Heliocentric" means Sun centered-that the Earth revolves around the Sun.

日心说就是指太阳是中心，地球围绕太阳转。

2 .Aristarchus recognized from his calculations that the Sun was much larger than the Earth and other planets.

通过计算，阿利斯塔克斯认识到太阳比地球及其他行星都大很多。

3 .It was probably this discovery that led him to conclude that the universe is heliocentric.

可能正是这项发现让他得出日心说的结论。

4 .I mean, isn't it more sensible to think that a smaller heavenly body would orbit a larger one, rather than the opposite?

也就是说，小型的天体围绕大型的天体转动不是更说得通吗？反之，则不然。

1 .However, his proposition was rejected, largely based on other scientific beliefs held at the time- which all made sense in a way, even if they were incorrect.

然而，他的提议却在当时得到了极大的打击，很大程度上是基于当时所持有的其他科学信仰，即便当时的科学信仰在并不正确，但是在某种意义上来讲也都说得通。

2 .Let me mention two objections Greeks made to Aristarchus' theory.

让我来提一下当时对阿里斯塔克斯理论的两个反驳。

3 .First, they believed that everything that moves creates its own wind, so to speak- everyone has this experience when you're running, right?

首先，他们认为一切运动的物体都会产生风，这么说，每个人在跑的时候都有所体会吧。

4 .So they thought that if the Earth itself was moving, there would have to be a constant wind blowing, sweeping them off their feet- and of course there wasn't.

所以他们认为如果地球在运动的话，那么就会不停的刮风，将他们刮倒，当然了，并没有风。

1 .And second, the idea of an Earth that moved didn't fit in with the ancient Greeks' understanding of gravity.

其次，地球运动的理论不符合古希腊人所理解的地球引力一说。

2 .They thought that gravity was basically a natural tendency of all things to move towards the center of the universe- which was the Earth, or the center of the Earth.

他们认为地心力就是所有物体被宇宙的中心所吸引，也就是地球，或者说地球的中心。

3 .So that explained why apples and other falling objects were falling straight down.

这也就解释了苹果或者其他掉落物体径直下落的原因。

4 .If the Sun was at the center of the universe, things would fall toward the Sun-and away from the Earth. Which of course they didn't. So these were some of the reasons they rejected the heliocentric theory.

如果太阳是宇宙中心的话，那么一切物体都会朝着太阳方向的去，而事实并非如此。所以这些就是他们反对日心说的原因。