Last night I went to bed with the TV on. I thought I'd multitask, listening to a PBS documentary about Herbert Hoover and falling asleep at the same time. I was surprised to learn—and eager to tell people at cocktail parties from now on—that Hoover, a self-made orphan, rose to prominence because he actually invented a system for large-scale relief, feeding 9 million starving Belgians throughout World War I!

Oh, how I would have amazed my friends and confused my enemies by talking about how Hoover went down in history as an uncaring laissez-faire Republican who left Americans to starve during the Depression.

I would have, if I hadn't dozed off at about the 14-minute mark.

I tell another anecdote about adult learning and television when I give speeches on speechwriting. It illustrates why it's so important to focus speeches not on three ideas or even two, but rather one, and one alone. (Or, as James Carville once described his job as a communication aide: to "empty full vessels.")

One evening a few years ago I sat down with a glass of wine and started clicking through the channels. I lighted like a butterfly on the beginning of a PBS special on dogs. The documentary would specifically address, the sonorous narrator explained, why dogs, all descended from the wolf, now come in so many shapes and sizes.

Well that's a damned interesting question, I thought to myself, and worthy of the next hour of my life.

Then the narrator explained that there are two theories as to how a relatively homogeneous population of wolves begat the modern canine-ucopia.

Oh, damn, I thought. I know my mind, and I know I'm not going to remember two theories. I'm only going to remember one theory.

But I hunkered down anyway, and listened intently as the narrator explained the first theory. It guesses that when people started domesticating wolves, they picked only the gentlest ones, thereby causing an artificial selection process which mated gentle wolves with gentle wolves and created mutations that eventually led to the chihuahua and other biological abominations that scurry between our feet and bark at nothing and shake, shiver and shit on little pads in the corner. (Don't get me started.)

And what was the other theory? I ask the audience rhetorically.

I don't remember the other effing theory! I bellow in freshly felt frustration.

The lesson for communicators being: It's hard to get stuff into grownups heads. Grownups always go around calling kids "sponges." It's not that kids are sponges. It's just that kids can actually learn stuff. Why? Brain theories aside, they have other advantages: They're not too self-conscious to fully listen, they're not immediately packaging every lesson for some practical use, they're not terrified somebody's going to quiz them and humiliate them for not remembering, and they don't drink wine.

But why kids learn and grownups don't isn't the point.

The point is: If you're gonna get an idea into a grownup's head, you've got to hit hard, straight, often and from different angles.

And since getting ideas in grownups' heads is what we do for a living, it seems we ought to keep this squarely in mind.

Now, what was I saying about Herbert Hoover? Oh yes …..