One of my favorite bumper-stickers reads, don’t believe everything you think.
Science is built on applying this sentiment. Doing science requires not quite believing things until you test them - over and over again. As a very simple example, think about a toddler dropping things off the side of her high chair. She is doing science and testing her emerging theory that things fall when pushed off the edge of the tray. But, like all good scientists, she isn’t quite ready to believe everything she thinks – so she needs to do more tests. Maybe the left side is different? How about the back? Does sliding or tossing make a difference? It is the persistent tests – and not quite believing the result of any single test – that make her overall theory more believable.
The same is true for more complicated ideas. Newton developed an idea of gravity, relating motion to the masses of objects, and it seemed to work pretty well. We tested it in lots of ways, from an apple off a tree (or high-chair) to predicting the motion of the planets around the Sun. And it mostly worked – but some people still didn’t entirely believe it. One person, Einstein, was particularly troubled that Newton’s ideas didn’t really explain the motion of Mercury. In fact, Mercury moves in a way that was very slightly different than what Newton’s idea predicts. Einstein came up with a new idea, general relativity, that works well at explaining Mercury, explains everything Newton’s idea did, and predicts all kinds of new things – most of which have been verified by experiment. So, we believe it, for the most part and for now.
This idea of not believing everything you think is so important to science that we’ve made it part of our culture and our way of working. The best scientists try to question their results all the time, but just in case we have a peer-review system in which friends and rivals sit around and try to disprove your ideas. At the end of the day, you get credit if your ideas survive.
This absolutely applies to climate change. Climate scientists at NCAR and elsewhere spend a lot of time trying to test the idea of climate change and look for holes or mistakes. Some research suggests they actually are more cautious in their predictions than they need to be. In other words, they are really living up to the adage “don’t believe everything you think.” If anything, they are underestimating future change.
As important as this skepticism is to the progress of science, it has its downfalls. Science isn’t for the faint of heart. If your friends are trying to prove you wrong all day, imagine what your rivals are doing.
Given that, I wonder if we scientists can be a little more encouraging to each other. Especially when we are working with new scientists we need to be careful to be skeptical of people’s ideas without being skeptical of the people themselves. Also, it is worth remembering that skepticism is a job skill, not necessarily a life skill. Critical questions are great in a seminar room, but much less endearing durring a romantic dinner.
The “don’t believe everything you think” philosophy means that there is always some level of uncertainty in science. But even following this philosophy can be dangerous if not believing everything you think turns into not believing anything you think. This can paralyze action.
Thanks to Newton’s theory of gravity, we could be pretty sure that apples would continue to fall from trees even if there was uncertainty about how gravity applied to the orbit of Mercury. Today, we are in a similar situation when it comes to the science of climate change - there are aspects about which we are uncertain, but overall we get the big idea. Just as apples will fall down and not up, climate is warming today and we need to decide as a society how to respond.
Not to get metaphysical (or is it episitemological?) we can even believe too much in the value of not believing everything: we scientists can be too dismissive of other ways of knowing about, and interacting with, the world – and we can be especially dismissive of those ways of knowing that don’t follow all the methods of science. This can isolate us from the very issues to which we could contribute. For example, I am not sure it does a climate scientist any good to be dismissive of the economic and political concerns and issues associated with mitigating climate change. In some ways, the bumper sticker is a good reminder. Because you think science is a good way of learning about the world, don’t fall into the trap of believing that it is the only way of learning about the world.
For me, it comes down to being questioning. Don’t believe everything you think means challenging your ideas - subject them to tests and you’ll be doing good science. At the same time it means avoiding the temptation to believe exclusively in the process of science. Recognize that unrelenting skepticism can be alienating, paralyzing if it dismisses the need to act, and isolating if it diminishes other ways of knowing.
At least, I think that’s what it means....