A lot of people don't believe there's evil. If there's good in this world, then you're being intellectually dishonest, if you believe there's a good power, you've also got to believe there's an evil power, too. There are physical laws that are in place.
In the winter, things are dead and dull, but then there is an explosion of life. That's what He promises people who believe in His Son. That's what all the Robertsons are banking on.