chapter 11

So much then for the voluntary movements of animal bodies, and the reasons for them. These bodies, however, display in certain members involuntary movements too, but most often non-voluntary movements. By involuntary I mean motions of the heart and of the privy¹ member; for often upon an image arising and without express mandate² of the reason these parts are moved. By non-voluntary I mean sleep and waking and respiration³, and other similar organic movements. For neither imagination nor desire is properly mistress of any of these; but since the animal body must undergo natural changes of quality, and when the parts are so altered some must increase and other decrease, the body must straightway be moved and change with the changes that nature makes dependent upon one another. Now the causes of the movements are natural changes of temperature, both those coming from outside the body, and those taking place within it. So the involuntary movements which occur in spite of reason in the aforesaid parts occur when a change of quality supervenes. For conception and imagination, as we said above, produce the conditions necessary to affections, since they bring to bear the images or forms which tend to create these states. And the two parts aforesaid display this motion more conspicuously⁴ than the rest, because each is in a sense a separate vital organism, the reason being that each contains vital moisture. In the case of the heart the cause is plain, for the heart is the seat of the senses, while an indication that the generative organ too is vital is that there flows from it the seminal⁵ potency⁶, itself a kind of organism. Again, it is a reasonable arrangement that the movements arise in the centre upon movements in the parts, and in the parts upon movements in the centre, and so reach one another. Conceive A to be the centre or starting point. The movements then arrive at the centre from each letter in the diagram we have drawn⁷, and flow back again from the centre which is moved and changes, (for the centre is potentially multiple) the movement of B goes to B, that of C to C, the movement of both to both; but from B to C the movements flow by dint⁸ of going from B to A as to a centre, and then from A to C as from a centre.

Moreover a movement contrary to reason sometimes does and sometimes does not arise in the organs on the occasion of the same thoughts; the reason is that sometimes the matter which is passive to the impressions is there in sufficient quantity and of the right quality and sometimes not.

And so we have finished our account of the reasons for the parts of each kind of animal, of the soul, and furthere of sense-perception, of sleep, of memory, and of movement in general; it remains⁹ to speak of animal generation.

The End

1 privy   

adj.私用的；隐密的

参考例句：

• Only three people,including a policeman,will be privy to the facts.只会允许3个人，其中包括一名警察，了解这些内情。
• Very few of them were privy to the details of the conspiracy.他们中很少有人知道这一阴谋的详情。

2 mandate   

n.托管地；命令，指示

参考例句：

• The President had a clear mandate to end the war.总统得到明确的授权结束那场战争。
• The General Election gave him no such mandate.大选并未授予他这种权力。

3 respiration   

n.呼吸作用；一次呼吸；植物光合作用

参考例句：

• They tried artificial respiration but it was of no avail.他们试做人工呼吸，可是无效。
• They made frequent checks on his respiration,pulse and blood.他们经常检查他的呼吸、脉搏和血液。

4 conspicuously   

ad.明显地，惹人注目地

参考例句：

• France remained a conspicuously uneasy country. 法国依然是个明显不太平的国家。
• She figured conspicuously in the public debate on the issue. 她在该问题的公开辩论中很引人注目。

5 seminal   

adj.影响深远的；种子的

参考例句：

• The reforms have been a seminal event in the history of the NHS.这些改革已成为英国国民保健制度史上影响深远的一件大事。
• The emperor's importance as a seminal figure of history won't be diminished.做为一个开创性历史人物的重要性是不会减弱的。

6 potency   

n. 效力，潜能

参考例句：

• Alcohol increases the drug's potency.酒精能增加这种毒品的效力。
• Sunscreen can lose its potency if left over winter in the bathroom cabinet.如果把防晒霜在盥洗室的壁橱里放一个冬天，就有可能失效。

7 drawn   

v.拖，拉，拔出；adj.憔悴的，紧张的

参考例句：

• All the characters in the story are drawn from life.故事中的所有人物都取材于生活。
• Her gaze was drawn irresistibly to the scene outside.她的目光禁不住被外面的风景所吸引。

8 dint   

n.由于，靠；凹坑

参考例句：

• He succeeded by dint of hard work.他靠苦干获得成功。
• He reached the top by dint of great effort.他费了很大的劲终于爬到了顶。

9 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。