The most basic ethical guideline for public speaking is this: tell your audience the truth. How do you feel when someone has lied to you or intentionally misled you? If you’re like most people, you resent it and feel manipulated. Audience members who discover that a speaker has deceived them seldom believe anything that person said—and they rarely do what he or she asked of them. They also remember being lied to. A known liar will have trouble ever convincing future listeners of his or her credibility or trustworthiness.

That being said, the words truth and truthfully are fairly subjective and elude precise definition. It is easier to describe truth in public speaking by examining what is not truth.