> abandance of evidence where in formal publishing or software UI, every text of 看 was replaced with 睇.

How would you even know it was replaced there? It's not like you can compare what the person was saying and what the person ended up writing.

In places where you do have access to both Cantonese speech and written text (e.g. movie subtitles), you can easily find such examples.

> The meaning of 睇 was defined as in 礼记·内则 like "睇，倾视也。"

The meanings change. Look at another word¹ from your example, 也 jaa⁵. 也 jaa⁵ used to be sentence-final marker roughly² corresponding to “to be” (XY也 ≈ X is Y), now it means “also” (我也唔知 = I also don't know).

Should we say that 也 jaa⁵ means “is” and not “also”? I don't think it it's useful.

Similarly, we shouldn't say 睇 tai² means “to look sideways”: it means “to watch, to read” in modern Cantonese. Just like 也 jaa⁵, it's meaning changed, and it’s OK. That’s how all languages work.

(BTW, neither Wikisource's nor Ctext.org's editions of 禮記·內則 even have this phrase. Could you give the link to the version of 禮記·內則 from which you're quoting this?)

> Why are making shit up to appropriate a Chinese word as some kind Cantonese excluse invention and misleading people.

I'm not saying it’s a Cantonese-only invention. I’m saying 睇 tai² is a standard Cantonese word for “to watch, to read”, and its cognate is not used in this sense in Standard Mandarin. Its cognate is sometimes used in other senses (I even gave an example of 睇視 [睇视] di⁴shi⁴ in Mandarin), but it’s not a standard word for “to watch, to read” (that's 看 kan⁴ in Mandarin).

It's similar to saying that “pas” is a French word for negation³, and it’s not used in this sense in Portuguese. Does it mean meanings (notably, “step”) do not exist? They do! Portuguese does have a cognate of “pas”, “passo”, but it only means “step”, it’s not a negation word.

> More importantly, there does exist another type of written Chinese, simplified vs traditional

Simplified and Traditional is comparable to Roman and Fraktur in German. Mandarin and Cantonese is comparable to Luxembourgish and High German.

You can write Mandarin in both Simplified and Traditional. You can write Cantonese in both Simplified and Traditional script.

Similarly, you can write Luxembourgish with Roman and you can write it with Fraktur. You can write High German with Roman and you can write it with Fraktur.

The language and character forms are orthogonal. (Even though some forms have more letters than others. E.g. Fraktur distinguishes ſ/s, while Roman type usually doesn't. Likewile, Traditional distinguishes 繫/係, while Simplified doesn't.)

> Would you proceed to argue HK style writing is Cantonese and not Traditional?

As I've said, these things are orthogonal.

Let's look at example of Cologne:

Spoken language = Colognian, written language = High German, script = Roman type.
(You can write Colognian, but most people translate their speech into High German when writing.)

Similarly, in Hong Kong: spoken language = Cantonese, written language = Mandarin, script = Traditional characters.
(You can write Cantonese⁴, but most people translate their speech into Mandarin when writing.)

(There's also phenomenon of a mixed language with Cantonese pronunciation and Mandarin grammar and words, sometimes called “High Cantonese”. It can be compared to Russian izvod of Church Slavonic: combination of Russian pronunciation with Old Bulgarian grammar and words.)

> Or even further maybe Guangdong and Hongkong cantonese are
> different "language" ?

Guangdong is big. Standard Cantonese, as spoken in Guangzhou and Hong Kong, is clearly the same language.

But Hoisanese? Probably divergent enough to be considered a separate language.

_____

¹ Or morpheme. The usual caveats about “what is a word” apply.

² I say “roughly” because Classical Chinese had several words that can be translated “to be”. The pre-Classical phrase for “X is Y” was X誰Y也, where 誰 used to mean “is”, but later disappeared (except when it was extra-stressed to mean “only”), and 也 took the meaning of copula (it was originally a sentence-final marker fo continuous situations). Even in ancient Chinese the meanings were already changing!

³ Interestingly, the development of Classical Chinese meaning of 也 jaa⁵ “to be” (X誰Y → X誰Y[也] → X[誰]Y也) is similar to development of French meaning of pas “not” (X ne Y → X ne Y [pas] → X [ne] Y pas).

⁴ You can find some books in Written Cantonese here: https://cantoneseforfamilies.com/free-online-cantonese-liter...