I’m sorry for mixing terminologies. But moving goalposts isn’t adequate to describe the full hilarity of the kinds of arguments denialists make. For instance, the goalposts never have to be moved when they require evidence that places them somewhere in the land before time. What I mean is the use, by denialists, of the absence of complete and absolute knowledge of a subject to prevent implementation of sound policies, or acceptance of an idea or a theory.
So while moving goalposts describes a way of continuing to avoid acceptance of a theory after scientists have obligingly provided additional evidence that was a stated requirement for belief, impossible expectations describes a way to make it impossible for scientists to ever prove anything to the satisfaction of the denialist. They’re related though so we’ll group both together.
Let’s take the example of the global warming deniers. One finds that they harp endlessly about models, how much models suck, how you can’t model anything, on and on and on. True, models are hard, anything designed to prognosticate such a large set of variables as those involved in climate is going to be highly complex, and I’ll admit, I don’t understand them worth a damn. Climate science in general is beyond me, and I read the papers in Science and Nature that come out, blink a few times, and then read the editors description to see why I should care. But with or without models, which I do trust the scientists and peer-reviewers involved to test adequately, that doesn’t change the fact that actual measurement of global mean temperature is possible, and is showing an alarmingly steep increase post-industrialization.
The next thing the global warming deniers harp on is about how we don’t have enough records of temperature to make a educated statement about whether our climate is really heating up that much as the instrumental record only goes about 150 years back. Then you show them proxy records that go back a thousand years, and after they’re done accusing people of falsifying, they say it’s still not enough, then you go back a few tens of thousands of years, and it’s still not enough, then finally you go back about 750 thousand years and they say, that’s just 0.0001% of the earth’s history! That’s like a blink of the eye in terms of earth’s climate. Then you sigh and wish for painless death. I’ll let real-climate fight the fights over proxy records and CO2 lag, because, simply, they know a lot more than me, and if you really want to argue with global warming denialists I recommend reading A Few Things Ill Considered’s Faq first. But what I can recognize is the tendency of the global warming deniers to constantly move the goalposts back and back, and once they whip out the argument we’ve only got proxy measurements for a fraction of earths life (a mere few hundred thousand years), you know they’ve graduated to impossible expectations.
A person who wasn’t just obviously stonewalling would say after you’ve shown them this much data that maybe we should take the data as is before we’re all under water. You don’t need to know the position of every molecule of air on the planet, throughout the entire history of earth to make a prudent judgement about avoiding dramatic climate change. (If they say that we don’t know what ideal is say, “yeah, but Florida will still be under water). You don’t need to know the position of every molecule in the galaxy before deciding you need to jump out of the way of a speeding train. Similarly, we don’t need to have a perfect model of the earth’s climate to understand that all the current data and simulations suggest decreasing carbon output is of critical importance right now, and not when humans have obtained some impossible level of scientific knowledge.
The honorary gif for making these tiresome arguments is – the goalpost (and no Chris you may not animate it).
P.S. This does not mean that I endorse all efforts to model complex systems. In the future I’ll probably complain about some modeling implementation of systems biology which I tend to think is total BS. I’ll explain the difference then.
P.P.S To see an example of some really hilarious creationist goalpost moving see our post on Michael Egnor demanding biologists provide an answer for something he can’t even define.