Cao Zhang and the inscription on the left are recognized. The content is:
The doctrine of the mean says: a gentleman fears what he has not seen and what he has never heard of. Don't be invisible, don't be insignificant.
Cui Zimo Geng Yindong. ''
Such exquisite calligraphy should be the original of the famous calligrapher Cui Zimo.
You can try to offer a reward of 1000 wealth value and see if anyone is willing to help you find it. 1000 wealth convertible 1 yuan 4.3 points. But to understand these eight words, it may take most of the time of ordinary literati.
If you have time, you might as well look it up yourself. You can buy a Liu Shutong, and only this book can be found.