Mystery
Mystery can be seductive. If we are not careful it can lead us into god-of-the-gaps thinking. We can be lulled into thinking that because something is so lacking in explanation we can explain it away as miraculous. This is bad science, bad theology and bad philosophy. Mystery can point to common sense. And mystery can establish criteria.
All too easily some of us who are religious can be lulled into thinking that because something lacks an explanation it must be miraculous. Such thinking is bad science, bad theology and bad philosophy. Mystery can point us towards common sense. Mystery can challenge us to find answers. But it is never ever proof of anything.