Quote from : The Sunday Philosophy Club Book

She had argued for a broad interpretation, which imposed a duty to answer questions truthfully, and not to hide facts which could give a different complexion to a matter, but on subsequent thought she had revised her position. Although she still believed that one should be frank in answers to questions, this duty arose only where there was an obligation, based on a reasonable expectation, to make a full disclosure. There was no duty to reveal everything in response to a casual question by one who had no right to the information.