I believe that bilinguals are smarter because of the positive effects of juggling two languages. The NYT article "Why Bilinguals are Smarter" writes that, Previously bilinguals were assumed to be cognitively hindered by the interference presented by the second language. Now several studies have shown that that interference actually improves brain functioning in problem solving, ignoring distractions, and holding information while switching attention between subjects. Also, The explanation for this benefit seems to be that suppressing one language in order to speak another “requires keeping track of changes around you in the same way that we monitor our surroundings when driving,” Bilinguals not only performed better on multiple tests but did so more efficiently.
I believe that, the process of changing ideas from one culture and one language to another is a big step and in this process the mind works better for bilinguals. also the ability to store and memorize too many words is a very hard thing, and if bilinguals were not smart enough, it would not be possible for them to learn more.
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