I visited a behavioral psychologist friend’s home in the U.S. about a year ago. While there I got a call from someone back home. We had been speaking English but of course my phone call was in Japanese. He mentioned to me that very often when a person who speaks several languages associates a language strongly with a specific culture, place and social group that person actually changes when they switch languages for more than about a sentence. He mentioned this because he watched me closely while I was on the phone and found the Jekyll/Hyde thing interesting to observe first hand.
The whole idea seemed very odd to me at the time, but he insisted that inside of us are a bunch of different flavors of our own psyche, or several semi-conflicted psyches all cohabiting — and our external personality is a sort of amalgamated manifestation of psychological combinations we find appropriate for a given situation. Or something like this. I’m not a psychologist, so this is probably a horrible mangling of an idea he explained quite succinctly to someone (me) that doesn’t grok the first thing about this.
He went on to explain that (again, bad paraphrasing) language is the gateway to many thought processes, because at very high levels of consciousness we abstract complex ideas behind words, even in our own heads most of the time, and that unspoken context and meaning carries a lot of weight as well — but that since we cannot “hear” this context in the monologues of our mind, we just don’t give it much conscious consideration. So basically, switching languages also switches the context of your thinking to some degree, and context is how you pick which flavors of your psyche are appropriate to manifest at a given moment, and so on. So switching languages also makes you sort of switch programs in your head.
Anyway, he’s an expert, so I take this into consideration, and that was that. Fascinating idea, isn’t it?
I just realized today something interesting when a friend (who doesn’t speak Japanese) asked me “what is takoyaki” and I realized that, explained in proper English, it doesn’t sound very good. “Sort of like hushpuppies or donut-holes with pickled ginger in the batter and octopus pieces inside” is a rather unsatisfying explanation. It only gets worse if you explain what 鰹節（かつおぶし） is and explain that no, it is not leftover shavings from carpentry work (though it is made using a planer…).
But! If I explain using a few loan words, it is great: “Like a hushpuppy with beni-shoga and tako inside!” See? No trouble.
たこ焼き and イカ焼き sound delicious. “Octopus” and “squid” not so much. That’s probably why Americans order “fried calamari” instead of saying “fried squid” — scores way lower on the Captain Nemo’s Dinner Horror Scale.