请求详细分析一个句子的语法结构，并翻译

Question

原句子：for to every brain-modification, however small, we suppose that there must correspond a change of equal amount in the consciousness which the brain subserves.
上一句是：for an identical sensation to recur it would have to occur the second time in an unmodified brain.
背景文字：有些间接的推断认为，随着我们感知能力的变化，我们的感知也在不断发生根本的变化。根据大脑所发生的必然变化，必须补充另一种假设。即相应的感知也会随着大脑活动而发生变化。
不好意思，我问题中的“上一句”是“上上一句”，这句话的‘上一句“是But as this, strictly speaking, is a physiological impossibility, so is an unmodified feeling an impossibility;句末是是分号

Answer 1

for to every brain-modification,状语前置，但只是短语不是句子所以不是二楼说的那样是状语从句。
however small, 插入语
we suppose that there must correspond a change of equal amount in the consciousness which the brain subserves.主句。由定从宾从组成。suppose后由that带出宾从。宾从里又套一个定从由which带出修饰先行词the C。
翻译就是你背景介绍说的那段中文。

for an identical sensation to recur it would have to occur the second time in an unmodified brain.
for an identical sensation to recur目的状语前置。
it would have to occur the second time in an unmodified brain.主句。
你的那段话我粘贴过来了。

A、To these indirect presumptions that our sensations, 对于XXXXX 状语前置
following the mutations of our capacity for feeling, 主语
are always undergoing an essential change, 这个我也不知道是啥。估计是接前面的to那句。但不确定。其实这句才是我不懂的句子。
must be added another presumption, 主语的谓语动词must be added和宾语another presumption

based on what must happen in the brain.过去分词做后置状语。是must be added的状语。
B、Even sensation corresponds to some cerebral action.这句的主谓宾你不可能不懂吧。
C、for an identical sensation to recur it would have to occur the second time in an unmodified brain.这句上面解释了。
D、But as this, 但因为这个。
strictly speaking, 插入语。严格意义上说。
is a physiological impossibility, 生理上是不可能的。
so is an unmodified feeling an impossibility;所以这是对不可能性不变的感觉。分号。
for to every brain-modification, however small, we suppose that there must correspond a change of equal amount in the consciousness which the brain subserves.对每个大脑的变化，虽然是很小的变化，我们假设在大脑促进的意识中大脑回应的变化量都是一样的。
这句话的结构在开头解释了。
其实我在这些句子里发现了巨多语法也好表达也好的问题。但是也不知道是作者错了还是我错了。我先去问问别人再来回复你。

还有，你的这个句子在这里有参考。有个七级的高人回答的。
http://zhidao.baidu.com/question/320245205.html
但我很想知道为什么这么多人问这个句子啊？我感觉这个句子身世很神秘啊。三个对这个句子的提问都是同一天出现的。两人对这个问题提问。其中有一人对这个句子提问两次~！！！

追问

都是来自同一个辅导班的学员，呵呵

追答

你们是什么辅导班啊

Answer 2

？

Answer 3

we suppose that there must correspond a change of equal amount in the consciousness 这个句子是主句
which the brain subserves.
定语从句
for to every brain-modification, 状语从句
however small插入语 做补足语 修饰前面的 every brain-modification
主句又是一个含有宾语从句的句式。

翻译：对于每一个大脑的修正活动，尽管这个变化很小，我们认为在由大脑支配的感知中一定有个同等量变化的回应。