Speaking two languages rather than just one has obvious practical benefits in an increasingly globalized world. However, in recent years, scientists have begun to demonstrate that the advantages of speaking more than one language are even more fundamental than the ability to converse with a wider range of people. Being _________, it turns out, makes you smarter. It can have a profound effect on your brain, improving cognitive skills that are not related to language and even shielding against dementia in old age.