Agreeing with the author of the submitted article that learning a new language is a wonderful thing, and agreeing with you in your capsule summary of the Sapir-Whorf hypothesis (linguistic relativity hypothesis), I have to respectfully register disagreement with the strong version of that hypothesis. Most people are stuck in their thinking because of evolutionarily developed cognitive illusions that are not language-specific.
Many people can be very creative and think thoughts that have never been thought before by their fellow language-speakers even if they are resolutely monolingual. And many of the features of language that might seem to be the most influential on human thought (e.g., whether or not a language has strong concord for grammatical gender) in practice don't seem to lead to any differences in thinking.
That said, even though the strong version of the Sapir-Whorf hypothesis is wrong, it's still a good idea to learn a new language. That does, at the very least, expose a reader or listener to authors or speakers from a different cultural tradition, and that does tend to result in new ideas and new approaches to identifying and solving problems.
http://www.project-syndicate.org/commentary/stanovich1
Many people can be very creative and think thoughts that have never been thought before by their fellow language-speakers even if they are resolutely monolingual. And many of the features of language that might seem to be the most influential on human thought (e.g., whether or not a language has strong concord for grammatical gender) in practice don't seem to lead to any differences in thinking.
That said, even though the strong version of the Sapir-Whorf hypothesis is wrong, it's still a good idea to learn a new language. That does, at the very least, expose a reader or listener to authors or speakers from a different cultural tradition, and that does tend to result in new ideas and new approaches to identifying and solving problems.