Here's why:
* Authorship: Some books were co-authored with other scientists.
* Editions: Many books have multiple editions, making it tricky to count.
* Types of publications: This includes scientific papers, textbooks, memoirs, and more.
However, some of his most well-known books are:
* The Double Helix: A personal account of the discovery of the structure of DNA (1968)
* Molecular Biology of the Gene: A classic textbook co-authored with other scientists (multiple editions)
* Avoid Boring People: Lessons from a Life in Science (2007)
To get a precise number, you would need to consult a complete bibliography of James Watson's publications.