As mentioned in ‘First, let’s get things straight‘, this isn’t a difficult rule to apply. It doesn’t mean “be devoid of preconceptions“. It just means “get rid of the ones you have the ability to notice“. And as mentioned in ‘First, let’s get things straight‘, that’s easy to do. You don’t have to change your beliefs or anything. You just have to explicit your preconceptions. That way, when someone else comes along and looks at your science, you’ve done your best to ensure they are not locked out of it for the wrong reason that they don’t share your beliefs.