It’s a very interesting and funny traditional Japanese custom, existing around 500 years already and so beloved by all children.
In the previous article («How to Understand Each Other? Talk to An Infant») we studied, going into details, how people interact as intelligent beings. We “arranged” with you about speech origin as first attempt to share inner ideas and try to communicate. We came to conclusion that up-to-date optimal form of suchlike interaction is language.
But languages are different… Was it so all the time in the past?