Oh, come on... maybe get some interest in history and dig through at least some of the things that you are touching.

Paper is written in 1944. None of that was true for that time and does not apply to modern days at all. It seems to be influenced by pre-war mystical New Ageish movements in Europe, that claimed many things... like, that Europeans came from Tibet...

I'm really confused about definitions here. What we define as Western, Chinese, Indian civilization and what we define as civilization at all.

You can like it or hate it, but modern Chinese nowadays belong to Western civilization - they use Western inventions(and they still steal them - no offense, but I think, it is a right thing to do for them to get into better economical position and you should do the same) - phones, computers, mechanisms, medicine, sanitation, building, use western clothing and even Mao spread western ideas... At this point Chinese civilization as such certainly does not exist and it is a myth. Same applies to others.

Let's clarify some things about Western civilization:
Western civilization does not apply exclusively to Western Europe.
Roman Empire, that was melting pot of nations and cultures was spread in northern Africa and for most of what is considered world of Islam.
Not bothering with colonies, core lands of ancient Greeks were in what is now called west of modern Turkey. Most of the world still does not know about great Chinese works, but they too don't predate works of ancient Greeks(as they were written more recently). There certainly existed even more ancient literature works in ancient China, but so did in civilization, what we consider western.

What you are talking about continuity of Chinese applies the same to Europeans as well, as they stem from steppe people, that were initially located in Eastern Europe and they even more efficiently than Chinese replaced local population. Heck, those steppe people even invaded civilization of Indus valley, eventually destroying it and replacing male population for most of northern India. Talk about continuity of ancient India - did you meant Tamil people or Harappans? Because if Harappans(Indus valley civilization) is considered Indian, then Tamil ancestors are thought to come from somewhere west of India and are not really native to India... unlike Veddas in Sri Lanka or Sentinelese of Andaman islands.

Now some nitpicks:
Goths did not left any traces of Gothic civilization in Italy - besides, how do you even dear to consider Goths not belonging to Roman Empire, as they were employed by Romans! As far as I know, Goths did not invade only Italy, but also invaded Spain and settled in most fertile part of Roman Empire - Africa, so they walked over whole Roman Empire.
There was no specific civilization of Britain during Saxon invasions. What did they even replace? And how do you differ them from Normans, Angles or even earlier Viking invasions? For all I know - all of them might belong to the same culture.
Because of Spanish conquest, Americas are now considered part of Western civilization. Aztecs came from deserts of modern USA and were rulers over natives, so what's your point? And even then Aztecs were not unique civilization, but only part of civilization region of what we call Mesoamerica.
Isn't is a hypocrisy to consider multiple states of China, that fought among themselves as continuous civilization(even today there are 2 Chinese states)... while looking on different European countries, who share the same civilization not consider them as continuous...