Japanese cultural isolation allowed for unique cultural development.

Evidence

But lying right at the end of all the great Asian trade routes and isolated by sea, Japan, unlike almost any other culture, was able to opt out of this interconnected world. — Neil MacGregor, A History of the World in 100 Objects, 919

Categorization

• corroborated: 2 independent passages support this claim — Neil MacGregor, A History of the World in 100 Objects, 919