Many people think that Jia Baoyu's prototype is probably Cao Xueqin himself, which means that the story in A Dream of Red Mansions is Cao Xueqin's own family affairs. It is for this reason that Cao Xueqin can write this novel so realistically that it seems to be something around him after reading it.
Of course, for any author, when writing a novel, things in real life will not be written into the novel, and there will be subtle changes. This is a sublimation of literature, and it is this sublimation that can be called literature.
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After textual research, people found that, in fact, in addition to Jia Baoyu, many characters in it have prototypes in real life, such as Shi Taijun, then Cao Xueqin's grandmother, that is, Cao Yin's wife; Shi Xiangyun's prototype is Jia Baoyu's cousin;
Qin Keqing is the daughter of Emperor Kangxi, also known as the princess. Lin Daiyu and Xue Baochai have the same prototype.
It should be safe to say that every character in A Dream of Red Mansions can find the prototype in real life. Without these archetypal figures, Cao Xueqin could not have created such a great work.
Baidu Encyclopedia-Dream of Red Mansions