I took Nathan to be referring to https://globalprioritiesinstitute.org/david-thorstad-three-mistakes-in-the-moral-mathematics-of-existential-risk/ and https://globalprioritiesinstitute.org/david-thorstad-high-risk-low-reward-a-challenge-to-the-astronomical-value-of-existential-risk-mitigation/ -- Thorstad’s blog (https://ineffectivealtruismblog.com/) has some summaries/further discussion, so far as I remember.
I took Nathan to be referring to https://globalprioritiesinstitute.org/david-thorstad-three-mistakes-in-the-moral-mathematics-of-existential-risk/ and https://globalprioritiesinstitute.org/david-thorstad-high-risk-low-reward-a-challenge-to-the-astronomical-value-of-existential-risk-mitigation/ -- Thorstad’s blog (https://ineffectivealtruismblog.com/) has some summaries/further discussion, so far as I remember.