The world is filled with countless other inventions. Scientists like the Doctor are the busiest of people. They are always trying to change the world. I’m not sure why they weren’t happy with the way things were before.

The world is clearly much different now than the one we remember. Not everything was invented in the beginning. Like sound and color, some things took time to take hold. Some of the most beautiful things, some of my favorite things in this world, were created as afterthoughts: like sunsets and shadows and the phases of the moon. You see, some inventions are truly wonderful.

And happiness, too – my favorite invention so far. Yes, even happiness was an afterthought. It happened quite accidentally. It started with a lovely sentence. One person said, "I love you." (I assure you this was a common phrase a long time ago, even if it has gone out of fashion lately.) But even though everyone began saying "I love you," you might be surprised to learn that the people were not truly happy yet. Saying "I love you" was apparently not enough. And saying it was difficult for many people.

This is especially true of the Doctor. She always seems more than a little troubled, so I try asking her to say "I love you," if only to the walls. She refuses outright. "Please don’t ask me to do that," she says. "This isn’t the time nor the place, especially for that." You have to believe me, I didn’t mean to offend her. I was not aware how busy the Doctor is. She hasn’t the time even to speak three words! Although she must certainly know what’s best for herself, I still think it’s strange to have to pencil in a time to say "I love you."

ii. secrets society One day, someone said, "I love you" – and added one thing more. "I love you," he said, "but you may never tell anyone!" That was the day when the curious takeover of secrets began.

I will admit, too, that saying "I love you" is not enough to make people happy anyway. Most people are not like you and I, Reader. Happiness came into this world in an altogether unexpected way. One day, someone said, "I love you" – and added one thing more. "I love you," he said, "but you may never tell anyone!" That was the day when the curious takeover of secrets began. They spread over the world faster than a blink of the eyes. Almost as quietly as wonder, everybody had told one another, "I love you," and whispered slyly, "but you may never tell anyone!"

That was a long time ago, but of course the Doctor does not remember. Even if she has forgotten, though, you can see it on all the people’s faces. It’s such a marvelous thing to see people happy. But they are strange creatures. Make no mistake about it: people are not happy because of the love, of course. That would be absurd! They are happy because of the secret.