I would say it’s extremely unlikely that the Macedonian army could conquer China. However if Alexander managed to do so The entire of China would soon rebel. Their immense numbers would overwhelm and repel the Greeks.
我认为马其顿军队是不可能征服中国的。 但如果亚历山大企图这样做的话，整个中国都会很快反击。 他们的巨大人口将压倒和击退希腊人。
This was because the Greek army was extremely small compared to the population and cities in China. Population density in China is much larger than in Europe. A Greek army of 40000–50000 men was equivalent to any army of a medium state in China in the Spring-Autumn period.
这是因为希腊军队与中国的人口和城市相比起来极小。 中国的人口密度远远大于欧洲。 在春秋时期，一个4万至5万人的希腊军队只相当于中国的任何一个中等国家军队。
Once Alexander’s army was dispersed. The Chinese would turn violent and crushed the Greeks from cities to cities.
Chinese written language is ideograph. Chinese written language can accommodate variety of spoken languages. That’s one of the reason China is united while Europe is not.
China have a fair governance ideal named 王道 which view it subjects the same regardless race or ethnic difference. Chinese dynasty is not western empire. Western empire rule by racial or religious discrimination. The racial or religious discrimination existed in China not as major political mold nor as a ideal.
That’s why Chinese civilization is the only survivor of Human cradle civilization. If Han Dynasty conquered west the civilization of the west died. If Alexander the Great conquered China Greek civilization died and be replaced by Chinese civilization.
Assume in 320s B.C. Alexander the Great continued to march to China.