Gnothi Seauton

The Oracle said Know Thyself.

Polonius said basically the same thing.

I really appreciate this take on it from Roger Ailes:

Another critical point: once you reach a comfortable, successful level of communications, you never have to change it, no matter what the situation or circumstances or the size of the audience. I define an audience as anyone other than yourself.

Whether there's one person or a thousand people listening to you, or if you're on television and there are millions watching [or if you're posting on the Internet and no one is watching - Dan] the essential principles hold true. The key element is that you not change or adapt your essential "self" to different audiences or different mediums. The thing that most confuses people trying to learn to be good communicators is the idea that somehow they have to act differently when giving an after-dinner speech than they would while being interviewed on television or for a job, or while conducting a staff meeting. They think they have to act all these different ways and nobody's given them the script to do this. Remember: You are the message, and once you can "play yourself" successfully, you'll never have to worry again.

Roger Ailes, in case that name is just vaguely ringing a bell, certainly has a track record of communicating effectively. These days he's blogging too, of course.

And I see Poor Richard muses (no, not that Poor Richard)

No need to reach for the stars, either, because when you know and are true to yourself, the stars are inside you. Love to cook and invent your own recipes, like Silence? So you’re not the next Emeril or Rachael Ray. Maybe you’ll end up giving the occasional lecture on garden-fresh cooking, as Silence does, to small but enthusiastic audiences. Maybe you’ll end up publishing a cookbook. Maybe you’ll just continue to delight family and friends with your creations. Whatever the end result, it’s the joy of cooking and creating the dishes that’s the real deal. Anything else is extra.

Bonus link: The Internet says The Oracle may have heard it (stolen it?) from Egyptians.