How does one properly tell someone they are blantly wrong, if you have been taught the subject so well?

Question

I had a discussion with a friend of mine on the subject of nationalism, and how it is relatively new. It is derived from colonization, India is a great example, and it is basically a group of people with a mechanized purpose, as the great Tagore put it. I was taught this well in my Global Studies class, a friend who enjoys arguing stayed firm on her belief that nationalism existed in ancient times, which is not possible since it is a direct creation of Capitalism. Yes, some may have used Capitalist elements, but the large society did not use them, or even share Adam Smith's notion of how wealth is measured (Labor). As you could imagine, I was greatly irritated by her objections. The basic fact is she was making a complete fool of herself and would sound completely ridiculous in front of someone who knew the subject well. I tried as best I could to explain this to her, but she just was not listening. Is there any way to change her mind on these facts or should I simply quit?

Answer 1

Ask her to give examples.