"Whenever your silence can be understood by others as agreement with what was said, you have an obligation to speak the truth. This way no one will mistakenly think that you agree with what was said.
Moreover, you can never tell; perhaps you will be successful in influencing others to make positive changes. A person who is not very assertive might find this difficult. However, learn from the person who says things that should not be said. If he is able to say something that he shouldn't, you certainly have a right to say those things that should be said. He is not afraid to say something improper; you should have the courage to speak up out of idealism!"

....I know this picture has nothing really to do with this post, but I love it and just had to post it anyway...