Asher looked at Anita, warm and alive and innocently curious. He forced a smile.

It seems like he's trying to preserve her innocence in this sentence. A "not betray her curiosity by pushing her into deep waters when she can't swim and isn't expecting the shock of cold waters" type of situation.

CatherineCookmn: Larry Niven is goooooood...I'm halfway through The Integral Tree. Very exciting and adventurous science fiction.