Why don’t people care as much as you?
When you are committed to a cause it's easy to think that the only reason other people don't feel the same is that they don't understand.
Your reaction might be to bombard them with evidence – facts, figures, statistics – anything that supports your position.
The only trouble is that this is exactly the sort of information that is likely to act as a barrier to your unengaged prospects.
Though your most committed supporters might be happy to wade through an avalanche of information, few others have the interest or the time.
Instead, they want you to do the hard work for them and provide an arresting and emotionally rewarding route in to your charity.
This facet of human nature was neatly summarised in diagramatic form by a chap called Poliakov in his Pyramid of Engagement published by the CoFSiM Research Centre.
So rather than than trying to create a 'rational' argument for your next mailing pack, focus on moving someone emotionally instead.
If you need some statistics to back this up, you can find them here.