Hearing develops before vision.
Hearing is one of the first senses to develop in a fetus. A baby can hear its mother's voice long before it is born. Vision comes at a latter stage. This was only known recently. However the Quran insists that God created our hearing before our vision.
[Quran 76.2] We created man from a fertilizing sperm, to test him; and We made him hearing and seeing.
[Quran 23.78] It is He who produced for you the hearing, and the eyesight, and the feelings. But little gratitude you show.
The Quran always refers to the "hearing" before the "seeing" which turned out to be their actual order of creation.
How could an illiterate man who lived 1400 years ago have known that hearing develops before vision?