The fact that educated Americans in general no longer share understandable background knowledge is a chief cause of their inability to communicate effectively.
意志疎通のはかり方は、文化によって決まるからである。
Knowing their languages is not enough to communicate effectively, because the methods of communication are determined by their cultures.
意志疎通によってお互いを知ることができる。
Through communication we are able to learn about each other.