Although she had no doubts of her own powers to sustain a role indefinitely, she had too much common sense not to recognize the force of Mr. Carter's arguments.
Mr. Carter has no doubts of her own powers but she doubts herself.
mnli hypothesis: Mr. Carter has no doubts of her own powers but she doubts herself. premise: Although she had no doubts of her own powers to sustain a role indefinitely, she had too much common sense not to recognize the force of Mr. Carter's arguments.