"I would never die for my beliefs because I might be wrong" - Bertrand Russell (philosopher)
Doubt is healthy. It is prudent to be flexible to adjust your beliefs or be open to somebody else’s view, as we expect other people to also be open and flexible to new ideas. But at the same time, you cannot doubt everything, all the time - it is simply unworkable (Are you sure that the sun rises tomorrow? Is it true that eating 3 hamburgers a day makes me obese?). That's why doubt should come in those healthy doses.
There is a huge amount of skepticism created around the issue of global warming, particularly whether is it anthropogenic (man-made) or just a natural phenomenon. Leading climate scientists are publishing study after study to demonstrate that our CO2 emissions are in fact the main reason that the planet is heating up. And at the same time, there are numerous publications trying to argue that the opposite is true: "You have nothing to worry about, simply continue what you were doing". If you look at our news headlines (and then I mean all of them, not just the ones that we have cherry-picked through your RSS and Twitter feeds) there can be only one conclusion, there is still doubt.
According to the scientific community and most environmental activists, this means the so-called climate skeptics or deniers have already won the debate. Because they don't have to prove the contrary, they just need to create the doubt. As long as the general public believes that the proof of man-made global warming is still inconclusive, our governments remain inactive.
I am arguing that this is no excuse for inaction. There is doubt and uncertainty about everything in our lives: Our relationships, our jobs, our competencies, our health. Yet we do not remain inactive. Instead, our brains deal with those uncertainties by assessing the chance (probability) of something happening, and its consequences, and then take the best decision. All of us are risk managers: while some of us literally make difficult decisions by writing the chances and consequences down, we all continuously risk assess in our heads about the choices we need to make on a daily basis. Whether you jaywalk to cross the street to save time or insist to search for the nearest pedestrian crossing is a choice you make after you have assessed the risks.
Sometimes we need to make important decisions but we are forced to rely on input from others in order to make our risk assessment: "Do I continue smoking or do I believe the medical experts who tell me that I am increasing the chances of a heart attack?" Even though most people do not have the skills or the knowledge to calculate the increased risk of a heart attack in relation to smoking, they are willing to follow the advice from medical experts. Why? Because the scientific community has built up a great reputation over the years and we know we can rely on peer-reviewed scientific research. They only make recommendations to the general public after elaborate research accompanied by extensive test results. Such tests are never 100% clear, but statistically they have sufficient value for society to let lives depend on it. Modern day medicine completely relies on this principle.
Of course scientists can make mistakes, so it is always good to keep that healthy dose of skepticism. That is why most of us look at the pros and cons of changing our behavior: "If the scientists are right and I don't quit smoking, then they say there is a high chance that I will die young. However, if I do quit, but the scientists turn out to be wrong, then the only risk is that I have deprived myself of the pleasure of smoking for no reason." So most rational people decide to quit - although not all: for some even risking their own life can be worth enjoying certain pleasures.
When it comes to our children though, then we all want them to stay safe, we want to minimize any possible risk. There has to be only one scientist who claims that playing with certain toys increases the chance of cancer and within weeks the whole country is aware, the toys are banned and the company goes out of business. We only want the best for our kids, right?
Now back to global warming: 97-98% of climate scientists worldwide agree that global warming is man-made. So even though, statistically, we should have enough confidence in these conclusions to accept them as true, maybe you are someone who believes that Fox News is a reliable news source or you think that politicians can give unbiased views on this matter that somehow outweigh the majority of scientists in the world. So maybe you feel the above conclusion is not 98% certain, but only say... 50% certain.
OK in that case let's look at the pros and cons of acting against global warming: If the scientists are wrong, then the risk is that we are forcing ourselves to stop using fossil fuels while we don't need to - at least we don't need to do it so quickly because eventually we will run out anyway - if not in the next 50 years then for sure in the next 100 after that.
Now if the scientists are right however, we will bring catastrophic and irreversible damage to our global climate once the levels of CO2 in the atmosphere reach 450 ppm. Today we are at 395 ppm and at the current rate we will hit 450 within the next 20 years. Once the climate spins out of control, billions of lives will be affected and our modern society as we know it will most likely cease to exist.
So with the information we have today we need to risk assess and decide on behalf of our (future) kids: Are we going to ignore man-made global warming, or are we going to do everything in our power to stop it, beginning today?