I'm 46. I came up with my idea at 28 but it was complex and ambitious -- and it just kept growing and changing. It was chaos in my mind. But I would work on it, and then come up a level, see things from a higher perspective and everything would shrink and consolidate, gain order and orthogonality. This happened over and over, till I got it down to nothing. This took a huge amount of time and there is no way I could have come directly to it at 28.

I'm as creative and as smart as I was then, I don't think that has changed. But I'm wiser now -- about Computer Science, about systems -- and I have that perspective, which has made all the difference.