Okay, there's one phrase that absolutely drives me up a wall. I do my best in all public interactions to stay cool and respectful of differing opinions and approaches to understanding, but when I hear these two little words I instantly Hulk out and start (mentally) smashing things:

"Scientifically proven."

I guarantee that if you hear that spoken to you, then you can immediately dismiss the speaker as a charlatan, a fake, a con, and/or an outright liar. They're trying to sell you something, and they're abusing the respectability of the scientific profession to pull you in.

Science doesn't prove anything. Anything. Every single statement we make about the world around us using the scientific method is provisional. They're based on the current accumulated evidence. All of our models, laws, hypotheses, and full-blown theories can be abruptly and unceremoniously overturned in a blink of an eye if new evidence comes to light.

And if a statement can be shown to be wrong tomorrow, then it can't exactly be "proven" today, can it?

Sure, there are some things we're pretty dang sure about the universe, like, I don't know, evolution of species and conservation of momentum, so it's not like we're losing sleep worrying that we can't make any scientific progress, but the principle holds true.

And there can certainly be accumulated evidence and statements of observation or experiment that are bare facts of our natural experience, but those statements are true or untrue, not proven or unproven, and they're usually much less interesting than you would hope (e.g., "under a limited set of controlled conditions, and subject to experimental uncertainty, we observe a 40% increase in an observed property compared to a control population.")

The scientific method is inherently inferential: today we make reaching statements that are conditioned on the available data and evidence. But tomorrow is, as they say, a new day.

What makes it so hard to talk about climate science? Of course the short answer is "politics", but why is it political, and why does that prevent us from speaking clearly about the subject? It's a perfectly respectable field of science, on par with physics, biology, chemistry, and all the rest (and it strongly overlaps with those fields anyway). And yet the subject is, for the most part, only hinted at or spoken about in the most oblique ways.

And I'm not just talking about COSI - science communication efforts across the world seems hamstrung by this topic. Are we afraid of upsetting audiences? Or donors? Or sponsors? Are we worried we might say something so offensive that we won't be allowed to continue our mission?

Probably yes, and probably for a good reason.

Astronomers can debate the nature of, say, dark energy for decades with basically nobody caring or even noticing, because the results of that discussion don't have immediate real-world consequences. It's of only literally academic interest. But our increasing understanding of the nature of the Earth's climate and humanity's impact on it drives major policy decisions, with ramifications totaling billions (trillions?) of dollars and affecting real human lives.

So yeah, it gets messy, real quick.

I think the breakdown in climate discussions occurs because sometimes we go too far. It's one thing to talk about the science: how we know that the Earth is getting warmer due to human activities. And it's totally cool to use scientific reasoning to forecast impacts on climate from decisions that face us now. But is it our place to advocate for certain policy decisions? I honestly don't know - it's an open question.

I do know that when we push a certain choice of what to do about climate change, we enter into the complex, emotional, highly charged world of politics. And when people's politics are threatened, they get defensive - if they don't like the policy, they're going to fight against it. And the first place to strike is at the base: questioning the basic science that led to that policy.

It might be that the climate well is so poisoned by now that honest discussions of the raw science are nearly impossible, and it's best to just stay out altogether. But maybe not. Maybe there's an opportunity to engage audiences with the fascinating, wonderful world of our study of the Earth's climate, and let them come to their own conclusions.

If we want to be known as respected, impartial facilitators of all science, perhaps we could start by being respected, impartial facilitators of all science.

When it comes to science, perhaps the most dangerous form of bias is simple wishful thinking. Oftentimes the data are extremely hard to come by in the first place, requiring huge investments of time, money, and hardware. After all that effort you probably really, really hope that your hypothesis works out. If it does, you get to publish, speak at conferences, and have a shot of getting your grant renewed. If it doesn't, well, maybe you can come up with a new idea?

So I'm sympathetic to scientists who unconsciously try to make their results look as good as possible. They're working in a broken system, with the number of their papers and the size of their grants determining their fate. But that subtle incentive introduces an ugly bias into the body of scientific research: apparent results that simply aren't there.

It's the job of the rest of the scientific community to a) be aware of that bias, and b) fight against it. You may have heard that some fields of science are facing a "replication crisis", where the majority of results are not holding up to further scrutiny. This is good! It's a sign that the field is self-policing and actively working against the implicit biases that lead to junk research. Imagine a world where we didn't even know these fields were facing a crisis, and the results were simply taken at face value. Is that world better or worse than our current situation?

For example, the CalTech astronomer Mike Brown and his colleagues argue that there is evidence for an additional massive planet in the outermost solar system, but many other astronomers argue against that hypothesis and present their own lines of evidence to counter. And he doesn't blame them - he even admitted during a recent talk that had he seen a competitor publish those same results, he would've scoffed and worked to disprove them.

Fighting bias in science isn't some lofty high-minded virtue. It's a result of natural human grubbiness and our desire to prove our opponents wrong and to demonstrate our own correctness. Progress in science relies on a community of healthy skepticism and open debate - those are the core principles that drive advances in understanding.