My native is Polish. As I live in the United States, I use mostly English, still imperfectly. Years back, I had a service business in Chicago with many Polish customers. Instant switching between the two languages was surprisingly very exhausting.

I fully agree that knowing other languages opens our minds. My halfway-decent knowledge of Russian gave me a window into the famous Russian soul.

Back in Poland, in college, we had many colleagues from Vietnam and East Germany. We did not know their native languages, but it was a great opportunity to peek into other cultures. When in Chicago, about half of my customers were people from all over the world. Again, intellectually stimulating experience for a curious person. Today, my family has members with a few different native languages. I live in Bolingbrook, Illinois, claiming to be the most ethnically integrated city in the United States. Let it be a consolation for Americans who speak only one language, talk to your neighbors.

But as Prof. Thomson writes, nothing can replace the knowledge of other languages because we live as many times as many languages we speak fluently.