the Challenge of Translation

The Challenge of Translation
I saw a difficult translation task here, http://www.italki.com/notebook/entry/196315.htm. How to translate “不打不相識” into English? We may get a quick answer from the Internet. Here it is:
No discord, no concord.

In real life translation, this can hardly be achieved. How can we translate it into English ourselves? Here are some possible literal translations:
People will not know each other until they fight against each other.
Those who have never fought against each other do not really know each other.

I think personally these are Chinglish because they make no sense to native speakers of English. People are strangers to each other because they have never struggled against each other. Does it make sense? I do not know President Obama, and he does not know me. If we fight each other, injuring each other, disabling each other, we will no longer be strangers. Is that the case? Apparently, this logic does not work. I know my good friend, so we have fought each other. Does this make any sense? Clearly, it is ridiculous.

We translate Chinese into English for one purpose and one only: to let native speakers of English know the meaning without the knowledge of Chinese. The challenge here is that certain meaning is implied in this Chinese idiom and it is omitted because native speakers of Chinese know the meaning without conscious. However to make the translation accurate, even native speakers of Chinese should turn to a dictionary for help.

指经过交手，相互了解，能更好地结交、相处。

Here comes a better one.
It takes a fight for people to know each other better.

Still it is not perfect. Do we have to fight in order to know each other better? It could be, but it is not necessarily a must. In English, we may say:
It could take a fight for people to know each other better.

Yet it sounds odd to say people being hostile to each other might be more likely to be friends. We know, this idiom is from “Outlaws of the Marsh “(“水浒传”). According to story in the novel, I think personally this version can be the right one.

People might get acquainted more easily to each other after they have accidently engaged in a struggle against each other.

In this version, I supplied the implied but omitted information so that it reads reasonable and can be understood. Although this version is relatively long, it can be safer in logic and intelligence.