Hi,
What does this sentence mean?
It’s a good father that knows his son.
To me, I think it means that (in the writer's opinion) if a father really knows his son's character and personality well, knows a lot about him, takes an interest in his life, then he is a good father.
According to its Chinese translation, it means "Even though he's a good father, he won't entirely know his son".
There's nothing in the English version to suggest that. There is nothing that equates to "Even though" nor does it say anything about "not knowing his son".
For your translation, you would need something like "Even the best father will never completely know his son".
When I first read Silver's sentence, I took it to mean 'If a father knows his son (well), then he is indeed a good father (and good fathers are rare)'.
Context is always important; labelling is rarely important.