It is a wise father that knows his own child.

[notletrest]

It is a wise father that knows his own child.
In China many English scholars once expressed their different understandings about it in a lot of magazines. My troubel is as follows:
1. What's the meaning of "know" here?
2.Is there any difference between it and others in the constructure of "It is somebody or somewhere or sometime that...." Is there any speciality of it and what is it in short ?
3.Which word ,father or wise , or a wise father,is stressed in it?
4.What's the real meaning of it?
Thanks a lot!

[Frank Antonson]

I am not sure if I understand all of your questions, but I would like to point out that "know" in English has a "semantic territory???" that includes what in both German and the Romance languages requires two words. In German, for example, wissen" means to know something like a fact, whereas "kennen" means to be to know something like a city or a person i.e. "to be familiar with". In your example, it would be the second meaning.