Verb
(set phrase) To recognize that a statement or belief is false or doubtful.
(set phrase) To understand that certain behavior is wrongful, futile, or inappropriate.
Source: en.wiktionary.orgMeasure a man by his actions fully, from the beginning to the end. Don't take a piece out of my life or a song out of my music and say this is what I'm about, because you know better than that. Tupac Shakur
To grow wiser means to learn to know better and better the faults to which this instrument with which we feel and judge can be subject. Georg Christoph Lichtenberg
Don't tell me you don't know what love is When you're old enough to know better. Elvis Costello
Who should know better than a cosmetician that human beings are less than rational creatures? John Brunner
All gardeners know better than other gardeners. Chinese Proverb
All gardeners know better than other gardeners. American Proverb