On your first comment, the Takakura et al (2019) study I mention and other models estimate a climate damage function, which is independent of a discounting module. The social cost of carbon is a function of a socioeconomic module, a climate module, a damages module and a discounting module as shown in the schematic below
Source: Resources for the Future, The Social Cost of Carbon: Advances in Long-TermProbabilistic Projections of Population, GDP, Emissions, and Discount Rates, October 2021
It is true that some models discount future costs in part with pure time preference. But I am here talking about the damage module which is the undiscounted aggregate damages, not the social cost of carbon.
Also, it is not true that all studies have a positive rate of pure time preference. The Stern review is one prominent counterexample, for instance.
I agree that some (though not all) models typically only consider impacts up to 2100. However, impacts up to 2100 are long-term relevant. If climate-economy models suggested that climate change would cause extinction or civilisational collapse or stagnation before 2100 (as some people seem to think is plausible), this would be long-term relevant. I agree that to get a complete picture, we would need to consider impacts past 2100, but we can still learn a lot from models that only go to 2100. Moreover, it would be practically impossible to build a useful complete climate-economy model running eg 1 million years into the future. It is more informative to explore how climate change might affect proxies of things that might have long-term import such as the risk of civilisational collapse or extinction. If you think we are in the hingiest or most important century, then the impacts of climate change this century are in fact the main thing that determine its long-term effects
If you think we are in the hingiest or most important century, then the impacts of climate change this century are in fact the main thing that determine its long-term effects
This is untrue if the things that make this century hingey are orthogonal to climate change. If this century is particularly hingey only because of AI development and the risk of engineered pandemics, and climate change will not affect either of those things, then the impacts of climate change this century are not especially important relative to future centuries, even if this century is important relative to future centuries.
All the indirect effects of climate that you consider are great-power conflict, resource conflict, etc. I have not seen arguments that claim this century is especially hingey for any of those factors. Indeed, resource conflict and great power conflict are the norm throughout history. So it seems that the indirect effects of climate on these risk factors is not only relevant for the 21st century but all centuries afterwards.
Takakura does not have a discounting module but considering impacts only up to 2100 is functionally the same as discounting all impacts after 2100. Obviously impacts up to 2100 are relevant to longtermists—my point is that they could be a substantial underestimate of its long-term effects. And you can improve on that substantially with a model that considers 500 years or something similar. It’s a baffling dichotomy to say that you can either consider impacts up to 2100 or millions of years.
This is untrue if the things that make this century hingey are orthogonal to climate change.
I do not think this is true. If we are at a hingey time due to AI and bio, and climate does not affect the hingeyness of this century, then it does not have much impact on the long-term.
Takakura does not have a discounting module but considering impacts only up to 2100 is functionally the same as discounting all impacts after 2100.
You initially said that Takakura et al has a discounting module because it endorses pure time preference. I pointed out that this is not true. So, this seems like changing the subject
I did not say Takakura has a discounting module and this is not changing the subject. What I said was:
I have an issue with Takakura and other models. All models I’ve seen measure climate impacts in a) a social cost of carbon, whose value is based on a pure time preference discount factor, or b) impacts by the end of the 21st century, which ignores impacts into future centuries.
Takakura has the latter problem, which is my issue with it as you use it.
If we are at a hingey time due to AI and bio, and climate does not affect the hingeyness of this century, then it does not have much impact on the long-term.
This doesn’t seem right as a criterion and is also counter to some examples of longtermist success. For example, the campaign to reduce slavery improved the long term by eliminating a factor that would have caused recurring damage over the long term. Climate mitigation reduces a recurring damage over the long term: if that recurring damage each year is large enough, it can be an important longtermist area. My point is that the impacts of climate in the 21st century are probably a substantial underestimate of their total long-term impact. It’s totally possible that when you account for the total impact it is still not important, but that doesn’t follow automatically from climates effect on hingeyness.
I’m not sure I understand your second comment. ‘hingey’ means that we are living at the most influential time ever. This includes things like value change around slavery.
Hi Karthik thanks for this comment.
On your first comment, the Takakura et al (2019) study I mention and other models estimate a climate damage function, which is independent of a discounting module. The social cost of carbon is a function of a socioeconomic module, a climate module, a damages module and a discounting module as shown in the schematic below
It is true that some models discount future costs in part with pure time preference. But I am here talking about the damage module which is the undiscounted aggregate damages, not the social cost of carbon.
Also, it is not true that all studies have a positive rate of pure time preference. The Stern review is one prominent counterexample, for instance.
I agree that some (though not all) models typically only consider impacts up to 2100. However, impacts up to 2100 are long-term relevant. If climate-economy models suggested that climate change would cause extinction or civilisational collapse or stagnation before 2100 (as some people seem to think is plausible), this would be long-term relevant. I agree that to get a complete picture, we would need to consider impacts past 2100, but we can still learn a lot from models that only go to 2100. Moreover, it would be practically impossible to build a useful complete climate-economy model running eg 1 million years into the future. It is more informative to explore how climate change might affect proxies of things that might have long-term import such as the risk of civilisational collapse or extinction. If you think we are in the hingiest or most important century, then the impacts of climate change this century are in fact the main thing that determine its long-term effects
This is untrue if the things that make this century hingey are orthogonal to climate change. If this century is particularly hingey only because of AI development and the risk of engineered pandemics, and climate change will not affect either of those things, then the impacts of climate change this century are not especially important relative to future centuries, even if this century is important relative to future centuries.
All the indirect effects of climate that you consider are great-power conflict, resource conflict, etc. I have not seen arguments that claim this century is especially hingey for any of those factors. Indeed, resource conflict and great power conflict are the norm throughout history. So it seems that the indirect effects of climate on these risk factors is not only relevant for the 21st century but all centuries afterwards.
Takakura does not have a discounting module but considering impacts only up to 2100 is functionally the same as discounting all impacts after 2100. Obviously impacts up to 2100 are relevant to longtermists—my point is that they could be a substantial underestimate of its long-term effects. And you can improve on that substantially with a model that considers 500 years or something similar. It’s a baffling dichotomy to say that you can either consider impacts up to 2100 or millions of years.
I do not think this is true. If we are at a hingey time due to AI and bio, and climate does not affect the hingeyness of this century, then it does not have much impact on the long-term.
You initially said that Takakura et al has a discounting module because it endorses pure time preference. I pointed out that this is not true. So, this seems like changing the subject
I did not say Takakura has a discounting module and this is not changing the subject. What I said was:
Takakura has the latter problem, which is my issue with it as you use it.
This doesn’t seem right as a criterion and is also counter to some examples of longtermist success. For example, the campaign to reduce slavery improved the long term by eliminating a factor that would have caused recurring damage over the long term. Climate mitigation reduces a recurring damage over the long term: if that recurring damage each year is large enough, it can be an important longtermist area. My point is that the impacts of climate in the 21st century are probably a substantial underestimate of their total long-term impact. It’s totally possible that when you account for the total impact it is still not important, but that doesn’t follow automatically from climates effect on hingeyness.
Fair enough on your Takakura point, I misread.
I’m not sure I understand your second comment. ‘hingey’ means that we are living at the most influential time ever. This includes things like value change around slavery.