Book II chapter 39

On Bodies which mutually repel² one another.

W riters who have discoursed³ on the forces of bodies which attract others have also spoken about the powers of bodies which repel, but especially those who have instituted classes for natural objects on the basis of sympathy and antipathy⁵. Wherefore it would seem necessary for us to speak also about the mutual¹ strife⁶ of bodies, so that published errors should not creep further, and be received by all to the ruin of true philosophy. They say that, just as like things attract for the sake of preservation⁷, so unlike and contrary things for the same purpose mutually repel and put one another to flight. This is evident in the reaction of many things, but it is most manifest in the case of plants and animals, which attract kindred and familiar things, and in like manner reject foreign and unsuitable things. But in other bodies there is not the same reason, so that when they are separated, they should come together by mutually attracting one another. Animals take food (as everything which grows), and draw it into their interior; they absorb the nourishment⁸ by certain parts and instruments (through the action and operation of the anima). They enjoy by natural instinct only the things set in front of them and near them, not things placed afar off; and this without any alien force or motion. Wherefore animals neither attract any bodies nor drive them away. Water does not repel oil (as some think) because the oil floats on water; nor does water repel mud, because the mud, if mixed in water, settles down in time. This is a separation of unlike bodies or such as are not perfectly⁹ mixed as respects the material; the separated bodies nevertheless remain joined without any natural strife. Wherefore a muddy sediment¹⁰ settles quietly on the bottom of vessels¹¹, and oil remains¹² on the top of the water and is not sent further away. A drop of water remains intact on a dry surface, and is not expelled from the dry substance. Wrongly therefore do those who discourse⁴ on these matters infer an antipathy (that is, the force of repelling¹³ by contrary passions); for there is no repelling force in them; and repulsion comes193 from action, not from passion. But their greek vocables please them too much. We, however, must inquire whether there is any body which drives anything else further off without material impetus¹⁴, as a loadstone attracts. But a loadstone seems even to repel loadstone. For the pole of one loadstone repels¹⁵ the pole of another, which does not agree with it according to nature; by repelling, it turns it round in an orbit so that they may exactly agree according to their nature. But if a somewhat weak loadstone, floating freely on water, cannot readily be turned round on account of impediments, the whole loadstone is repelled¹⁶ and sent further away from the other. All electricks attract all things: they never repel or propel anything at all194. As to what is related about certain plants (as about the cucumber, which turns aside when oil is applied¹⁷ to it), there is a material change from the vicinity, not a hidden antipathy. But when they show a candle flame put against a cold solid substance (as iron) turn away to the side, and allege¹⁸ antipathy as the cause, they say nothing. The reason of this they will see clearer than the day, when we discourse on what heat is195. But Fracastorio's opinion that a loadstone can be found, which would drive iron away, on account of some opposing principle lurking¹⁹ in the iron, is foolish.

1 mutual   

adj.相互的，彼此的；共同的，共有的

参考例句：

• We must pull together for mutual interest.我们必须为相互的利益而通力合作。
• Mutual interests tied us together.相互的利害关系把我们联系在一起。

2 repel   

v.击退，抵制，拒绝，排斥

参考例句：

• A country must have the will to repel any invader.一个国家得有决心击退任何入侵者。
• Particles with similar electric charges repel each other.电荷同性的分子互相排斥。

3 discoursed   

演说（discourse的过去式与过去分词形式）

参考例句：

• He discoursed on an interesting topic. 他就一个有趣的题目发表了演讲。
• The scholar discoursed at great length on the poetic style of John Keats. 那位学者详细讲述了约翰·济慈的诗歌风格。

4 discourse   

n.论文，演说；谈话；话语；vi.讲述，著述

参考例句：

• We'll discourse on the subject tonight.我们今晚要谈论这个问题。
• He fell into discourse with the customers who were drinking at the counter.他和站在柜台旁的酒客谈了起来。

5 antipathy   

n.憎恶；反感，引起反感的人或事物

参考例句：

• I feel an antipathy against their behaviour.我对他们的行为很反感。
• Some people have an antipathy to cats.有的人讨厌猫。

6 strife   

n.争吵，冲突，倾轧，竞争

参考例句：

• We do not intend to be drawn into the internal strife.我们不想卷入内乱之中。
• Money is a major cause of strife in many marriages.金钱是造成很多婚姻不和的一个主要原因。

7 preservation   

n.保护，维护，保存，保留，保持

参考例句：

• The police are responsible for the preservation of law and order.警察负责维持法律与秩序。
• The picture is in an excellent state of preservation.这幅画保存得极为完好。

8 nourishment   

n.食物，营养品；营养情况

参考例句：

• Lack of proper nourishment reduces their power to resist disease.营养不良降低了他们抵抗疾病的能力。
• He ventured that plants draw part of their nourishment from the air.他大胆提出植物从空气中吸收部分养分的观点。

9 perfectly   

adv.完美地，无可非议地，彻底地

参考例句：

• The witnesses were each perfectly certain of what they said.证人们个个对自己所说的话十分肯定。
• Everything that we're doing is all perfectly above board.我们做的每件事情都是光明正大的。

10 sediment   

n.沉淀，沉渣，沉积(物)

参考例句：

• The sediment settled and the water was clear.杂质沉淀后，水变清了。
• Sediment begins to choke the channel's opening.沉积物开始淤塞河道口。

11 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

12 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

13 repelling   

v.击退( repel的现在分词 )；使厌恶；排斥；推开

参考例句：

• He saw himself standing up and repelling a charge. 他仿佛看见自己挺身而起，打退了敌人的进攻。 来自辞典例句
• Promote the healthy entertainment styles. Repelling the superstition, gambling, drugs and obscenity. 提倡健康娱乐。抵制封建迷信活动，拒绝黄、赌、毒。 来自互联网

14 impetus   

n.推动，促进，刺激；推动力

参考例句：

• This is the primary impetus behind the economic recovery.这是促使经济复苏的主要动力。
• Her speech gave an impetus to my ideas.她的讲话激发了我的思绪。

15 repels   

v.击退( repel的第三人称单数 )；使厌恶；排斥；推开

参考例句：

• His manner repels me. 他的举止让我厌恶。 来自《简明英汉词典》
• Her callous attitude repels me. 她冷酷无情的态度引起我的反感。 来自《简明英汉词典》

16 repelled   

v.击退( repel的过去式和过去分词 )；使厌恶；排斥；推开

参考例句：

• They repelled the enemy. 他们击退了敌军。 来自《简明英汉词典》
• The minister tremulously, but decidedly, repelled the old man's arm. 而丁梅斯代尔牧师却哆里哆嗦地断然推开了那老人的胳臂。 来自英汉文学 - 红字

17 applied   

adj.应用的；v.应用，适用

参考例句：

• She plans to take a course in applied linguistics.她打算学习应用语言学课程。
• This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。

18 allege   

vt.宣称，申述，主张，断言

参考例句：

• The newspaper reporters allege that the man was murdered but they have given no proof.新闻记者们宣称这个男人是被谋杀的，但他们没提出证据。
• Students occasionally allege illness as the reason for absence.学生时不时会称病缺课。

19 lurking   

潜在

参考例句：

• Why are you lurking around outside my house? 你在我房子外面鬼鬼祟祟的，想干什么？
• There is a suspicious man lurking in the shadows. 有一可疑的人躲在阴暗中。 来自《现代英汉综合大词典》