分类不明:哪里来的那么多符号?

汉字(你现在看到的语言的书写体系),是从甲骨文甚至之前的文字演变而来的。严格意义上来说,现在的汉字不算是象形文字,算是语素文字,就是表意文字。

现代英语的字母是由腓尼基字母演变而来的罗马字母表的字母再演变而来的。其他字母文字大体上也是腓尼基字母的变体。请不要问我阿拉伯字母为什么会扭成那种样子。然后,日语的假名是汉字演变过来的字母文字,韩语/朝鲜语的谚文也参考了汉字,越南语的喃字就以下省略了。

化学就更尴尬了。古代中国还没有化学这个概念,你让字母文字写一长串?举个例子。

Phosphorus

你还敢说复杂的分子?

酚酞

Phenolphthalein

然后呢?

然后就是化学家跳不出象形文字的框框了。直到贝采里乌斯才有了现代的符号雏形。

物理基于数学,数学呢?

先从加号开始。

“et”,拉丁文的“和”,现在已简作“&”。这个“et”还演变成了加号,与塔塔里亚使用意大利语的“plu”的“μ”一样,都是草写成了加号,也就是“+”。

“-”号也一样,拉丁语的“minus”的m写草了写成了横杠,与我不谋而合。

简直了。

直到魏德美,德国数学家,正式于十五世纪确认了这两个符号。

乘号有不下十几种,现在只剩下了“×”与“·”两种。两个都有缺点。叉乘太像x,也就是一个未知数,点乘又容易看成一个小数点。

总之是会看成xx\left(x+1\right)=1.2的。

后来还有人说要用“\cap”表示相乘。这个符号现在用于集合论。

叉乘可由加号旋转得来,所以也被视为增加的符号,就保留了。点乘现在用于线段(也就是字母之间)的乘积,而叉乘与点乘在向量里面也有不同的意思。
“÷”一开始也是减号,直到有人用“:”表示比、除,用“—”(除线)表示除,才有了拉哈正式规定。

平方根曾用拉丁文“Radix”的首尾两个字母放一起表示。笛卡尔第一次用了“√”表示平方根,是字母“r”的变形,上方再加括线。

等于号“=”一开始表示两个量之间的差别,但是这么个平行又相等的线段,为什么不是等于呢?于是就变成等于号了。

“~”,莱布尼兹用它表示相似,下面加等号表示全等。

大于号小于号以及一堆括号就以下省略了。

任意/任取(全称量词)“∀”就是“Arbitrary”的“A”倒过来,同理,存在(存在量词)“∃”就是“Exist”的“E”翻过来写。

可见,这些符号的出现就是因为一个原因:

表达

可不是吗。

Lake桑

2019.1.6

思维导图:博客总结

点击下载使用 XMind 制作的博客总结的思维导图。

Lake桑

2019.1.6

每日一词:paradigm(转自 韦氏词典)

原文链接


Merriam-Webster’s Word of the Day for January 6, 2019 is:

paradigm • \PAIR-uh-dyme\  • noun

1 : example, pattern; especially : an outstandingly clear or typical example or archetype

2 : an example of a conjugation or declension showing a word in all its inflectional forms

3 : a philosophical and theoretical framework of a scientific school or discipline within which theories, laws, and generalizations and the experiments performed in support of them are formulated; broadly : a philosophical or theoretical framework of any kind

Examples:

“I was just obsessed as a kid with David and Goliath. It’s probably the ultimate conflict paradigm in literature. But I was always on the side of Goliath. I loved Goliath. I didn’t like David at all and I wished Goliath could win.” — Lee Child, quoted in The Spectator, 1 Dec. 2018

“Phoebe has a talent for taking a musical or poetic paradigm and tilting it, inverting the norm in a way that expands and challenges the boundaries of the standard. Her songs marry convention with experimentation, both with a musical arrangement and production, and in the actual poetry of the songs.” — Julien Baker, quoted in New York Magazine, 26 Oct. 2018

Did you know?

Paradigm traces to a Greek verb meaning “to show,” and has been used in English to mean “example” or “pattern” since the 15th century. Some debate exists, however, about what kind of example qualifies as a paradigm. Some people say it’s a typical example, while others insist it must be an outstanding or perfect example. The scientific community has added to the confusion by using it to mean “a theoretical framework,” a sense popularized by American scientist Thomas S. Kuhn in the second edition of his influential book The Structure of Scientific Revolutions, published in 1970. In that work, Kuhn admitted that he had used paradigm in 22 different ways. Some usage commentators now advise avoiding the term entirely on the grounds that it is overused.


Lake桑

January 06, 2019 at 01:00PM