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Pascal’s proof of God and climate change

Todd Whitcombe Science and You Three centuries ago, the mathematician Blaise Pascal came up with an argument in favour of believing in the existence of God.

Todd Whitcombe

Science and You

Three centuries ago, the mathematician Blaise Pascal came up with an argument in favour of believing in the existence of God.

It was set out in note 233 in the posthumously-published collection entitled "Pensees," which was a work on Christian apologetics. It took advantage of Pascal's mathematical genius and pioneering work on probability.

In essence, the argument comes down to drawing a table in which there are two rows and two columns. The first row represents the proposition that God exists. The second row represents the proposition that God does not. The first column is the proposition that one believes in God. The second is that one does not.

This leads to four possible outcomes: (1) God exists and you believe, (2) God exists and you don't believe, (3) God doesn't exist and you believe, and (4) God doesn't exist and you don't believe.

The essence of Pascal's argument is that believing costs you nothing but the payoff is everything if, in fact, there is a God. After all, it is only outcome (1) that would see a person get into "heaven," while outcomes (3) and (4) are neutral and outcome number (2) would see a person end up in "hell."

To Pascal this represented an irrefutable argument in favour of believing in a divine being, but that is not the topic for today.

Rather, the same sort of analysis can be applied to "doing something about climate change."

For climate change, we would use the same table of two rows and two columns. The first row is the proposition that anthropogenic climate change is occurring, while the second row is the proposition that it is not. That is, the first asserts that human activity is actually causing the climate to shift, while the second says that this is not the case.

Note that this doesn't mean that climate change isn't occurring - just that it is not a consequence of human-based activity.

The columns hold the propositions that "We do something about it" or "We don't do something about it."

All of this leads to four possible outcomes.

The first is that anthropogenic climate change is occurring and we do something about it. This will involve changing the way that we use energy - at all levels. We use about 30 to 40 times as much energy in our lives as people did a century ago. We have cell phones that are unnecessary and have computers left on 24 hours a day. We drive two blocks to the store instead of walking. And we live in cold climates instead of where it is warm.

We also live in single-family detached dwellings and build buildings out of concrete instead of wood. We waste heat energy instead of re-using it and we don't take advantage of free energy such as geothermal.

The list of things that we should change is long and will cost money, time, energy, and require ingenuity. But for the sake of the planet, this outcome would argue that we should take some action.

The second outcome is that climate change is not anthropogenic but we still do something. While it will still cost a lot of money, time, energy, and require ingenuity, this is not money, time, energy, and ingenuity wasted. Rather, it is working toward changing the energy consumption balance that we have with the planet. With fossil fuels running out and an increasing human population, these changes would be a "good thing" regardless of whether or not climate change is occurring.

The third outcome is that climate change is not anthropogenic and we do nothing. This isn't going to cost us a lot of money - provided the changes that occur are manageable. However, even "natural" climate change is going to do damage. It is going to result in increased rain fall in some areas and droughts in others.

Doing nothing to solve these problems is the most Darwinian of social practices - saying that only those who can afford to cope should survive.

The fourth outcome is the complete disaster scenario - climate change is anthropogenic but we do nothing about it.

In this case, our children and grandchildren will be left with the task of cleaning up our mess. Cleaning up a catastrophic environmental mess is not something that we should leave to future generations.

As with Pascal's proposition, the outcomes are clear. Doing nothing should not be an option - because it courts complete disaster.

The detrimental impact of the fourth outcome outweighs the expenses incurred in any of the other three.

Or, at least, that is the conclusion that logic and probability would lead one to believe.