Please help me to see whose seal this is. What are these words?

Cai's short answer? Know white

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Zuo yin Cai Bai zhi

Correct printing and understanding of white

Signature book (black words on the right)

The author Cai is a member of the National Association of Calligraphy and Painting for the Aged, China Literature Calligraphers Association and Yanbian Calligraphers Association.

Online dictionary seal: