阅读文本为 David Hume - A Treatise of Human Nature, DOVER PUBLICATION 2003版；中文译本为商务印书馆1980年关运文译本。
BOOK 1 OF THE UNDERSTANDING
Part2 of the ideas of space and time
the idea of EXTENSION 广延
- the idea of extension is nothing but a COPY of color'd points, and of the manner of their appearance
- omit the diffrences to shape the abstract idea of the assemble of the impression and take it as the resemblance.
we omit the peculiarities of color, as far as possible, and found an abstract idea merely on that disposition of points, or manner of appearance, in which they agree. (D.Hume:p25,2016)
- the impression of TOUCH is similar to the impression of SIGHT in the disposition of their parts
- e.g: a table 1. SIGHT (S)
2.TOUCH (T）
different color ➡ idea of COLOR
different feeling ➡ idea of FEELING
All abstract ideas are really nothing but particular ones, consider'd in a certain light; but being annex'd to general terms, they are able to represent a vast variety,m and to comprehend objects, which as they are alike in some particulars, are in others vastly wide of each other. (D.Hume:p25,2016)
- the abstract idea/quality is defined by difference in impression
-~~~ Ludwig Wittgenstein the concept of NUMBER （？
TIME (distinguish 2 concept: Co-existence vs Non-coexistence)
- the concept of TIME comes from the succession of impressions
- TIME is a kind of idea
- if there's no successive impression, we cannot feel time
- our perceptions have certain fixed bounds, beyond which external objects cannot exert an influence on our thought
- only perceivable succession of changebale objects define time (time cannot make itself appearance)
- THE PARTS of time (DURATION) are not co-existent, Co-existent PARTS consist of EXTENSION
- Separated - Distinguishable - parts
- THE IDEA OF TIME arises from the 【manner】 in which impressions appear to mind. No new emotion nor affection come into being but A NEW IDEA OF TIME.
- It may be hard to tell TIME if there's few distinguishable parts of a thing.
- original idea → contemplation （manner/form？：manner gives certain order of the impressions）→ the idea of the object → concenption of TIME
- The idea of 【DURATION】derives from a succession of changeable objects. Therefore the idea of DURATION is not the propriety or exactness of an object.
A disscusion of "the indivisible idea", taking EXTENTION as an example:
① The idea of time consists of the sense of SIGHT and the sense of TOUCH
② EXTENTION must be shown in the form of VISIBLE or TANGIBLE
③ VISIBLE or TANGIBLE are indivisible to the eye or to the feeling, eg.,maybe consist of atoms with color and solidity
④ the idea of ccolor or solidity compound the imagination of certain tangible parts - which can be conceived by our mind - composing the ideas of points/parts → composing the ideas of extention
⑤ Therefore we have the idea of an object through our sight or feeling, even if there's no concept of SPACE or TIME
⑥ There must be some real objets or existense in the indivisible moments of time，whose succession forms the duration.
Answering Objection 对反驳的答复
·The capacity of mind is not infinite - the idea of EXTENSION and DURATION cannot consist of infinit parts of inferior idea - SPACE and TIME are not infinitely divisible
· 思维有限，所以时空的观念并非无限可分 → 时空的观念会停留到不可分割的部分 → 但如果不可分割的部分并非实体或真实存在（sth real and existent）是难以想象的 → 时空观念是对象存在的方式或秩序（manner or order）
（无法现象没有物质广延(extension)，没有在实体中接续变化的时间）
·反驳经院派：广延无限可分，因为数学的点是个荒谬的概念，但数学的点是一个非实在物，无法与其他数学点结合起来形成一个真实存在。 （经院哲学：文艺复兴时期，力图用理性论证信仰，或者将理性范围和信仰范围严格区分。推动近代经验哲学和实验哲学。）
·反驳“相互渗透（penetration）”：人的想象不很容易构想单一的点那样的微小的对象。
· 反对广延可分：从数学的点线面入手，如同抓水银。如果我们有符合定义的、不可分割的点线面的观念，它们的存在就是可能的（possible）；但如果没有，就不可能有几何的证明。
· 重点在于：想象的最小概念；相等的标准
· 反对相等即相合（congruity）：把对象并列判断会出错（frequently correct our first opinion by a review and reflection）；转而用一种共同不变的尺度进行衡量。
Sound Reason - 要求我们相信除了感官前的物体还有更多微小的物体
False Reason - 要求我们相信还有无限的更微小的物体
· 曲线与直线：无法给出任何确切的定义（点→线→直线/曲线？），只能形成不知标准的模糊概念（看起来直不直）。
对于“两点之间最短距离是直线”——
①使用特性来定义（Definition vs Property, 亚里士多德式定义），则会变成两点之间最短距离的路线时总是最短的路线。
② 我们没有精确的“相等”与“不相等”的概念（同样较长、较短）。一个精确的观念不能建立在不确定之上（如平面的概念建立在直线的概念上）。
·休谟理论的基础在于人类理性标准薄弱的基础：
Our appeal is still to the weak and fallible judgment which we make from the appearance of the objects, and correct by a compass or common measure. (p37)
As the ultimate standard of these figures is deriv'd from nothing but the senses and imagination, 'tis absurd to talk of any perfection beyond what these faculties can judge of; since the true perfection of any thing consists in its conformity to its standard. (p37)
· 比例：无用的标准 - 从一些对象的一般现象中得出 - 不精确的标准 - 最初原则建立在想象和感官上
· 通过想象把两种有密切关系的观念联系到一起建立原理。现象是真实的，但说明可能是虚妄的。 类似 Resemblence, 接近 Contiguity, 因果 Causion
· 连接观念的过程是“灵的流动（spirit flow）”
· 人们常用“语词”代替“观念”，两者密切连接，但心灵容易把两者混淆。因果和类似造成了这种错误。（如用距离观念替代以某种方式分布的广延：假设了一种消灭，这种印象引起的观念（印象只能引起和它类似的观念）。）
· 与牛顿哲学相一致：
一个真空被肯定了；那就是说，物体被说成是出于这样一种方式，可以在他们中间接纳其他物体、而没有任何冲击或渗透。物体的这种状态的真实性质是不知道的。我们只认识到它对感官的作用和它接纳物体的能力。对于那个哲学来说，最适当的就是一种适度的温和的怀疑主义，同时坦率地承认对于超出一切人类能力的那些题材，我们一无所知.
· 洞察物体本性（nature）超出了人类执行范围，无法不借着感官外面的特性认识物体。← 康德
· 时间的观念来自于变化（时间本身不存在，是观念）。
存在也是一种观念，“存在的观念”与事物本身没有区别。
