text: If by nature you mean as a person is born, including heredity and genes, I believe this influences human behavior by about 50%.  However, the nurturing a human receives via parents, friends, teachers, and others a person meets and/or sees in life then influence a person's behavior by about 50%.  A person starts out with certain characteristics and learns to deny or appreciate, accept or seek out scenarios which then show that person what he/she enjoys or not.  Life is choices.  So I would need to say "both".