When visiting South Africa, Daniel the Englishman asked a South African the question:
"Why is it that some South Africans say 'Ja' (pronounced as "ya") while others say 'Yes' if they have the same meanings?"
"Clever people say 'Yes' while stupid people say 'Ja'," was his reply.
"So, are you clever?" asked Daniel.
"Ja," replied the South African.