Great to hear this has been useful!
I think if γ is around 1 then yes, spreading longtermism probably looks better than accelerating growth. Though I don’t know how expensive it is to double someone’s consumption in the long-run.
Doubling someone’s consumption by just giving them extra money might cost $30,000 for 50 years=~$0.5million. It seems right to me that there are ways to reduce the discount rate that are much cheaper than half a million dollars for 13 basis points. Eg. some community building probably takes a person’s discount rate from around 2% to around 0% for less than half a million dollars.
I don’t know how much cheaper it might be to double someone’s consumption by increasing growth but I suspect that spreading longtermism still looks better for this value of γ.
How confident are you that γ is around 1? I haven’t looked into it and don’t know how much consensus there is.
I just looked at the one paper. I’m not sure if other sources disagree.
Even if γ was 2 though, I still feel like it would be cheaper?
It’s hard for me to think about changing individuals, but if I think of governments: there some government department which is responsible for the welfare of some population. We have 2 options:
Convince them to update their models to move their discount rate from 2% to 1%, or
Convince them to adopt some policy which doubles the consumption of everyone within that population
Surely the first one is easier? If only because it’s at least in principle possible – even if the US government would magically do whatever I said, I don’t know if I could suggest a policy change that would double consumption.
Yeah, that seems right to me.
On doubling consumption though, if you can suggest a policy that increases growth consistently, eventually you might cause consumption to be doubled (at some later time consumption under the faster growth will be twice as much as it would have been with the slower growth). Do you mean you don’t think you could suggest a policy change that would increase the growth rate by much?
That’s a fair point. I guess the thought experiment could be something like: the department is responsible for some set of people’s welfare 50 years from now. We have to either convince that department to have a lower discount rate 50 years from now, or adopt some measures such that the people born 50 years from now will have doubled the consumption (relative to the counterfactual)?
If that’s right, the discount rate thing still seems easier. It seems hard to double consumption over a 50 year period, though definitely easier than doubling it immediately.