Consider the Science Channel. As I learned all of those years ago, this channel is never going to appeal to more than 25 percent of television viewers, the information seekers. That means, over the course of a month, that of the 80 million households who receive Science perhaps 20 million will actually tune in. You can see that as bad news, but for me it is a positive: most companies can only dream about their product being useful to 25 percent of the entire population.