To see what is right and not to do it is want of courage, or of principle.

Most failures of conduct are not confusion about right and wrong. You knew. What was missing at the moment of action was either the nerve to pay the cost or a conviction sturdy enough to make the cost irrelevant. Working out which of the two ran short is more useful than the general guilt that follows, because they are repaired differently.

Think of the last time you stayed quiet when you should have spoken. Ask whether you were afraid of the consequence or simply not certain enough to accept one. Then decide what would have to be true for next time to go otherwise.