I've been to Canada, Mexico, Panama, Honduras, Philippines, Indonesia, S. Korea, Vietnam, Turkey, Iraq, and all over western Europe. I have supped with people in marbled halls and in mud huts.
It taught me that truth is impossible to know unless one knows all sides of it. Each side has their own version of the truth and have their own embellishments and their own embedded lies. Only when you put them all together and see what fits the physical evidence can you determine the truth of a matter. Meanwhile, each side only wants you to know their side and no one elses. There are a few who would rather kill you than to let you learn anoother side to their story.
I've learned that there are a few universals to human behavior. If we cannot overcome these universals, our species is doomed to extinction.