In Um…, I mention Mohamed Sami Anwar, a linguist who, in 1978, described a long tradition in Arabic linguistics of noting and collecting errors, a tradition that predated Sigmund Freud and Rudolf Meringer by many centuries. It was never clear to me that the Arabs were collecting slips of the tongue, and now I know that they definitely weren’t.
For nearly all of its history, the Koran has been read by Muslims only in Arabic. As Islam spread, people who didn’t speak Arabic natively had to learn it, which changed the language, much to the chagrin of speakers of Classical Arabic. So the “pure” Arabs became shocked at the corruption of the language, and collected examples of these corruptions:
Ziyad ibn ‘Abihi sent for ‘Abu l’-Aswad and said to him: ‘O ‘Abu l-‘Aswad, these foreigners have multiplied and corrupted the tongues of the Arabs. Couldn’t you compose something to correct their language and give God’s Book its proper decelension?’
‘Abu l’-Aswad refuses — he has other things to do. So Ziyad ibn ‘Abihi sends someone to casually pass by ‘Abu l’-Aswad and say something from the Koran, but to make some mistake.
‘Abu l’-Aswad was shocked. He returned immediately to Ziyad and said to him: ‘I’d like to comply with what you asked me to do and I think it would be best to start with the declension of the Qu’ran.
This is much elaborated in Kees Versteegh’s excellent books about Arabic and Arabic linguistics. As Versteegh explains, other explanations for the birth of Arabic linguistics are also founded in observations of mistakes that are perceived to corrupt the language.