It's possible:
* You've misspelled the name: There might be a sociologist with a slightly different name, and the misspelling has led to confusion. Could you double-check the spelling?
* It's a local figure: Perhaps "Fr. Valentin Marin" is a prominent figure in a specific region or community, but not a widely known sociologist.
* It's a fictional character: It's possible you've encountered this name in a book, movie, or other fictional context.
To help me understand better, please provide more context:
* Where did you encounter this name? (e.g., a book, an article, a conversation)
* What was the context? (e.g., was he mentioned as a sociologist, a priest, or something else?)
With more information, I can try to assist you further.