As a fellow language lover I second the suggestion, but not the reasoning. What's your evidence for "some thoughts only make sense in a given language"? From what I've read, this isn't agreed upon in the linguistic community. As for Esperanto, it's heavily biased towards Western speakers, so it wouldn't necessarily be easy to start with for someone whose native language is non-Western.
On the most superficial level:
It's easier to talk about snow or numbers in languages that have more words for these concepts than in languages that have less.
Languages with lots of words for snow tend to be used places where there is lots of snow to talk about. Languages with few words for snow tend to be used in places that don't get much snow and thus don't need to talk about it.
In short, if you need to talk about any subject learn the local language (whatever that is) so you can talk to the locals about the topic.
Having recently listened to John McWhorter's lectures on the history of human language, I was surprised to find out that there is no reliable evidence for the Sapir-Whorf hypothesis (that language affects thought). The Wikipedia article on linguistic relativism states:
> The strongest form of the theory is linguistic determinism, which holds that language entirely determines the range of cognitive processes. The hypothesis of linguistic determinism is now generally agreed to be false.
English includes a lot more words than most people use regularly. I imagine that's the same in any language. Just expanding one's working vocabulary in one's native language would probably be quite helpful for thinking and expressing oneself more fluently—not that learning another language isn't valuable.
I'm told that English will create words for where other language create grammar. (which can be anything, from a new tense to prefixes to other things I cannot imagine because I don't know the language)
