I’m continuing a series of public speaking principles in the next few blog posts that are a summation of what I’ve learned about this fiendishly difficult art and science over three decades of practice, coaching, learning from others, and research, especially neuroscience.  Here are the next seven, about the conditions of speaking.

57.Props enhance a speech more than slides. In our information age, we spend too much of the time absorbing digital information, whether it’s via slide decks or email or pdfs. Adding a real, three-dimensional prop to illustrate a key moment of a speech will be far more memorable for the audience than another slide, even a picture slide.

58.Every speech at least implicitly addresses the three limitations of the form: the limit of the audience to retain information, the limit of the speaker to convey information, and the time limit. In this sense, every speech is always a triple failure – a failure of the speaker to convey a full picture, the failure of the audience to comprehend a complete story, and the failure of the speech itself to cover the material comprehensively.

59.The speaker and the speech are both in service to the audience. We reward keynote speakers handsomely, for the most part, because of their expertise and the difficulty of giving a speech. But that should not disguise that the most important leg of the triangle of speaker, speech and audience is the audience, because if that audience hasn’t heard and understood the speech, it might as well not have happened.

60.Prepare more material for a speech than you intend to give. You can always cut on the fly, but it is very difficult to vamp, so preparing more than seems necessary for the time allotted is the safer way to go.  While audience rarely complain if a speech ends early, meeting planners may feel cheated.

61.It is more important to move even one member of the audience than it is to deliver a perfect speech. The aim of a speech should never be perfection; rather, the speaker should strive to change the world, even if that means shocking, annoying, angering, or frightening the audience.  Human emotion is the important outcome, not flawlessly delivering your talk.

62.Success in public speaking, like everything else, follows the 80-20 rule. If you can move most of your audience to action, the speech can be rated a success.  You’ll never get 100 percent approval, and striving for that as a goal is to think about a speech in the wrong way.

63.The more successful a speech is, the more chaotic it will feel to the speaker and to the audience. That’s because a successful speech turns emotions loose in the minds of the audience, and channeling those emotions means letting the energy loose in action, a noisy and potentially chaotic process.  A great speaker understands this and doesn’t shy away from the ensuing chaos, but rather directs it in the right ways.

My goal in these principles is to explore the implicit rules of public speaking, the kind people rarely bring up in lists of the 10 rules for public speaking, which almost all start with “follow your passion” and end with “always end on time.”  Both are true and good bits of advice, but they don’t help speakers much beyond the absolute beginning steps.