I have a book I really enjoy, The Lost Sutras of Jesus. The story goes that a around 600 C.E. a group of monks went to China to teach Christianity. Their teaching got blended with Eastern philosophy, producing a set of teachings that reflected both cultures. A few hundred years later the teachings were hidden as the political environment changed and they weren't discovered again until the 20th century.
One particular quote I like is "There is no single name for the Way. Sages do not come in a single form. These teachings embrace everyone and can be adopted in any land."
From the project management perspective, I see this as saying there is no one way to run a project. Just because we are using a PMBOK approach (for example), doesn't mean we have to criticize Prince2 or Agile or any other approach. We can learn from all of them. We should always be open to other people's ideas.