Both are divinatory texts that should contain 64 prognostications (although the Irk Bitig contains errors leading to 65 prognostications) and both are known from China. Is there any historical evidence for a connection between them?
I ching is 3000 years old, while Irk Bitig is only 1100. But its written in Uigur Turkish so it means being close to China. And also it was written by Buddhist Turks, so there is a connection.
However in content, I believe they're not related that much. It is also worth noting how it is similar to Modern Turkish, despite 1100 years and nearly 4,500 kilometers.
Old Uighur Turkish: Boz bulıt yorıdı / budun üze yagdı / kara bulıt yorıdı / kamıg üze yagdı
Modern Turkish: Boz bulut yürüdü / Halkın üzerine yağdı / Kara bulut yürüdü / Kamu üzerine yağdı.