The dangers of bone-headed beliefs Surely it's time for climate-change deniers to have their opinions forcibly tattooed on their bodies. Not necessarily on the forehead; I'm a reasonable man. Just something along their arm or across their chest so their grandchildren could say, ''Really? You were one of the ones who tried to stop the world doing something? And why exactly was that, granddad?'' On second thoughts, maybe the tattooing along the arm is a bit Nazi-creepy. So how about they are forced to buy property on low-lying islands, the sort of property that will become worthless with a few more centimetres of ocean rise, so they are bankrupted by their own bloody-mindedness? Or what about their signed agreement to stand, in the year 2040, lashed to a pole at a certain point in the shallows off Manly? If they are right and the world is cooling - ''climate change stopped in the year 1998'' is one of their more boneheaded beliefs - their mouths will be above water. If not OK, maybe the desire to see the painful, thrashing death of one's opponents is not ideal. But, my God, these people are frustrating. You just know that in 20 years' time, when the costs of our inaction are clear, the climate deniers will become climate-denial-deniers. ''Who me? Oh, no, I always believed in it. Yes, it's hard to understand why people back then were so daft. It's so much more costly to stop it now.'' That's why the tattoo has its appeal. Read more: The dangers of bone-headed beliefsScratch a leftist, find a tyrant.