There is a blobby, rounded shape and a sharp, spiky shape. Which shape is the bouba and which one is the kiki? In tests, more than 90% of the participants will call the shapes with soft edges the bouba, and the pointy shape the kiki. Strangely enough, these answers remain consistent even among people from different cultures and who speak different languages. As reported by Psychology Today, "The bouba-kiki effect was discovered by German psychologist Wolfgang Köhler almost a century ago, and it has been tested in many languages, always with the same result." So, what gives? These two words are literally nonsense...

The bouba-kiki effect is an illustration of sound symbolism—the idea that certain sounds have certain primal meanings. Psychology Today explains, "Noted neuroscientist V.S. Ramachandran proposes that some degree of synesthesia is a core component of the human experience. Thus, as our pre-human ancestors began shaping their first words, they created sound symbols that in some way resembled the things or events they were referring to. Eons later, sound symbolism based on synesthesia was abandoned as vocabularies became large and unwieldy, leading to the arbitrariness in word forms seen in modern languages." Sure, calling a shape a bouba is goofy, but it tells us a lot about the history of language and meaning.

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