The prisoner’s dilemma is a classic philosophy problem, well-known to undergrads everywhere.

It imagines two co-conspirators in adjoining jail cells with no way of communicating. They are asked to testify against each other. Because of the nature of their crimes and the evidence the police have against them, the crooks will only do a year of time if neither gives evidence. If one flips, he goes free and the other guy gets three years. But if they both flip, they each get two years.

It’s a thought experiment that describes lots of real-world situations where there’s a need for collective action and where, if everyone acts in their self-interest, everyone loses.

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The fight against climate change is a good example. Countries like Canada know that cutting emissions will hurt in the short term and only pay off in the long term if other countries do their part, too. Not knowing what other countries will do, they feel tempted to spare themselves the trouble. But if enough countries think that way, we get catastrophic global warming and a world of pain for everyone.

Right now, the position of too many Canadian conservatives is to flip on the guy in the next cell. Since big emitters like the United States and China can’t be trusted to do their part, we might as well save our own skin and not bother with the complications of carbon pricing, the most efficient and effective way to reduce emissions, or even bother to offer a realistic alternative.

That would be both immoral and ruinous for our future. If we listen to the do-nothing crowd, we would be playing this prisoner’s dilemma all wrong.

The argument that Canada is too small to make a difference in the fight against global warming, and so shouldn’t try, has a certain surface appeal. We contribute just 1.6 per cent of the world’s greenhouse gas emissions. Even if that’s three times our share of the global population, it’s still not a lot.

As we beaver away earnestly at reducing our relatively meagre carbon output, the rapidly growing economies of Asia are spewing with abandon. China and India alone account for about a third of the world’s carbon dioxide emissions. And emissions in both countries continue to grow.

That’s discouraging, especially if the goal is staying under a particular warming threshold. The United Nations suggests our target should be 1.5 degrees above pre-industrial temperatures. Any more than that and we face major ecological disaster. To achieve that target, we need to cut global emissions in half by 2030, and go carbon-neutral by 2050.

The bitter truth is that we will almost certainly breach that threshold and face the consequences – rising seas, species loss, mass heat waves and water shortages in some of the world’s poorest and most unstable places.

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This is where some throw up their hands and say action is pointless. That attitude couldn’t be more wrong. After all, there are degrees of disaster. Every half-degree of warming puts more lives at risk, so every bit of action is worthwhile.

Looked at this way, Canada’s bit is actually pretty significant. We are the world’s 10th biggest emitter, ahead of France, Brazil, Turkey and South Africa. Our example matters more than our gross emissions. That’s a difference between our dilemma and the prisoner’s: The nations of the world can communicate with each other. And by taking serious action, Canada says to them, “Acting on the climate just got a little less futile for you.”

It’s worth remembering that responsible smaller countries can jointly put a dent in climate change. If you add up the carbon-dioxide output of the dozen or so relatively progressive countries among the world’s top 20 polluters – countries like Australia, South Korea and Japan – you end up with more emissions than the United States pumps out. Our carbon tax just gave these countries more reason to stay honest.

Reports of Chinese and American lassitude on the climate are exaggerated anyway. The United States has slashed its annual CO2 emissions by almost 800 million tonnes in the past decade, mostly by moving away from coal. Beijing is taking action, too: Its coal consumption peaked in 2013, and it looks likely to meet its Paris Agreement targets.

Canada is taking a leap of faith right now. Our Liberal government is banking that its carbon policy will contribute to a meaningful global effort towards mitigating climate change, and that we won’t be left looking like suckers. That’s our prisoner’s dilemma. We’re doing the brave and generous thing. Lucky for us, it’s also a smart bet.