Thoughts
读书，有时是需要借助外部的辅助的。
就我自己而言，读书或多或少地会用到书中所提到的几种辅助源，这其实是学习生涯中所积累下来的经验罢了。但是本书在这里进行了相关的总结，详细的论述以及给予必要的建议和注意事项，对于在阅读上野蛮生长的我们，很有帮助。
Summary
4 types of extrinsic aids
1. relevant experiences
-common experiences
--relevant to fiction, philosophy books and history books
-special experiences
--relevant to scientific works and history books
2. other books
-read them according to time order
-fiction and plays can be read in isolation.
3. commentary and abstract
use them sparingly
2 reasons
-is not necessarily right
-is not necessarily complete
1 advice
-read them after getting through the book
4. reference books
4 kinds of knowledge
-have some idea of what you want to know
-know where to find out you want to know
-know how the particular work is organized
-know it is considered knowable by the author or complilers of the book
4.1. dictionary
find out how to spell and pronounce words
4 points about words:
1.words are physical things--writable words and speak-able sounds.
2.words are parts of speech.
3.words are signs.
4.words are conventional.
4.2. encyclopedia
look up dates and places and other simple facts
4 points about facts:
1.facts are propositions.
2.facts are true propositions.
3.facts are reflections of reality.
4.facts are to some extent conventianal.
Words and phrases
1. partake
This is because history partakes both of the fictional and the scientific.
2. exhaustive
3. at one's mercy
4. digest
5. creep in
