Sentence:  'Do you think, sir,' said Mr Willet, ... 'do you think, sir, that I'm a born fool?'/ 'No, no, Johnny,' returned Solomon, looking round upon the little circle of which he formed a part: 'We all <WSD>know better</WSD> than that.' 
Meaning of the word marked with <WSD> tags:  To recognize that a statement or belief is false or doubtful.