Conversation so far:
What is meant by secular nature?
By the time of Horace Mann's leadership in education, various developments fostered a secular school system with a religiously passive stance.
What are some important aspects of secular nature?
Horace Mann stated that this position resulted in a near-universal use of the Bible in the schools of Massachusetts.

Question: Was Mann well known to a lot of people?
Self-contained rewrite: Was Horace Mann well known to a lot of people?