He means that in every argument or so, we must take sides, and personally, I don't think his argument is effective.
Explanation:
I'm assuming that Wiesel meant that everyone must choose sides for everything, for example, an argument. But, his statement is not strong enough. One, he's lacking reasons and he must provide sufficient reasons to support his statement. Two, he should be more specfic about it, someone may be confused on what he meant.
