Evolution is fact, just as gravity is fact. We may not always be able to

Graeme
explain evolution or gravity to everyone's satisfaction, but that does not mean they aren't facts.

The big difference between the two though, is that ANY schmoe on the street can observe gravity in action. Not so with evolution, which (to whatever degree it happens) happens in a way that can only be observed by those with highly specialized training.

It's when its supporters begin thinking of it as something intuitively obvious that no one could doubt, like gravity, or the sunrise, or whatever, that they're in danger of turning it into a bad religion.