An Inconvenient Question?

12/20/2007 04:07 pm ET Updated May 25, 2011

It's 1964. You are a 25-year old pack-a-day smoker (OK, maybe a pack-and-a-half, depending on the day). You started in your teens, and never gave the habit much thought. Smoking makes you feel more alert and focused; it gives you confidence, helps you stay slim, and if you don't say so yourself, you look quite debonair with a smoke hanging jauntily from your lips.

But there's a problem. You've just picked up the newspaper to discover this headline: "Scientists Establish Smoking Link to Cancer." According to the article, there is now an overwhelming scientific consensus that smoking causes cancer. This conclusion is the result of an exhaustive analysis of the scientific literature on the subject. It is unequivocal, and carries the weight of the most respected scientific institutions.

Of course, you have been aware of the research for some time. However, until now, it's always been couched in the language of uncertainty. Now the results appear to be in, and the news is grim.

Granted, there are still some scientists who disagree with the research, (including a few not on the payroll of the tobacco companies). These experts say that a direct causal link has yet to be established. They say that additional research is still needed. A few even deny outright that such a link exists. However, they are in the extreme minority.

Now you have a decision to make. If you keep on smoking, according to the best information currently available, you're likely to get cancer, the consequences of which are horrible pain and an early death. On the other hand, you are not certain to get cancer. The existing science only establishes a greatly increased risk. And quitting smoking will certainly result in significant short-term pain: intense physical withdrawal symptoms, irritability, lack of concentration, possible weight gain. Besides -- maybe those few contrarian researchers are right.

What do you do? Please indicate your answer here:

[ ] CONTINUE SMOKING [ ] QUIT SMOKING

Have you made your choice? Good. Now let's move on to the present.

It's 2007. You are an advanced industrial nation. But there is a problem. You've just picked up the newspaper to discover this headline: "Scientists Establish Human Link to Global Warming." According to the article, there is now an overwhelming scientific consensus that human-generated carbon emissions are responsible for a rapid rise in global temperature, with potentially catastrophic consequences. This conclusion is the result of an exhaustive analysis of the scientific literature on the subject. It is unequivocal, and carries the weight of the most respected scientific institutions.

Of course, you've been aware of the research for some time. However, until recently, it has been couched in the language of uncertainty. Now the results appear to be in, and the news is grim.

Granted, there are still some scientists who disagree with the research (including a few not on the payroll of the energy companies). These experts say that a direct causal link has yet to be established. They say that additional research is still needed. A few even deny outright that such a link exists. However, they are in the extreme minority.

Now you have a decision to make. If you maintain current emissions levels, according to the best information currently available, you're facing global warming, the consequences of which range from drought, flooding, ecosystem destruction, disease, extreme weather, population dislocation, resource wars, or a planet inhospitable to human survival. On the other hand, you are not certain to face these consequences. The existing science only establishes an increased risk. And curtailing carbon emissions will certainly result in significant short-term pain: lower growth, reduced consumption, possibly even lower standards of living. Besides -- maybe those few contrarian researchers are right.

So...what do you do?