Thanks for posting this here as well as Jess's excellent questions! This seems like a nice place to continue the conversation around the paper, so I'll respond to what I take to be the most pertinent issues in the blog post here. As Jess notes, this is a relatively early attempt to formulate these ideas and the literature on longtermist institutional reform is extremely young, so the more conversation the better.

How will (short-term) vested interests try to capture these in-government research groups, and how will that be prevented? Why is this better done within the government rather than done in academia using grants from the government or philanthropists?

Most governments are swamped with expertise. It's not that they have too little of it, but that they are overwhelmed with it, can't absorb it, and don't know who to turn to as a reliable source of information. Governments need one or a small body of epistemically reliable and nonpartisan research groups that they can turn to which fill the function of synthesizing extant research into consumable reports for government. These research groups in turn need to have strong working relationships and good lines of communication with government. If an academic or privately-funded research institute could play that role, that would be fine, but it's harder to see how this would be possible, and in-government research groups and advisory boards have a good track record of playing this sort of role. (We use the OTA as one prominent example, but there are many others on smaller scale.) One additional benefit of research institutes that are set up by government is that when the government is perceived as legitimate, these institutes will also be seen as legitimate and reliable sources of information. It would be valuable for the described research institutes to have public legitimacy, so that if their publicly disseminated research were ignored by government this fact could precipitate public censure.

If public censure isn't enough to command the attention of government to the research, then a research institute with government authority could also have the "put-it-in-their-face-power" we suggest in the paper, forcing reading and a response by government.

Short-term interest capture is an important worry, and we see this already in privately-funded research groups as well as in academia. One mechanism we propose in the paper for preventing capture by interest groups and industry is to have researchers selected by professional associations or by lot. If the research body is large enough and its key members and leadership are shuffled frequently enough, this should prevent a great deal of corruption. But of course, we are open to other ideas depending on the additional concerns that arise.

What will incentivize the citizen assembly to actually benefit future citizens? Merely because they are “explicitly tasked with the sole mandate”, with no enforcement or feedback?

The citizens' assembly proposed doesn't have a strong mechanism for amplifying the concern of assembly members for future people. It is assumed that they already have some interest in doing this, as roughly all people do. The role of the citizens' assembly isn't to amplify personal motivation, but rather to i) reduce election and funding incentives that disincentivize the electorate from focusing on the long-term, ii) reduce the deleterious effects of polarization on long-term deliberation, and iii) create designated agenda time for long-term issues. All of these sources of short-termism hamper governmental motivation to focus on the long-term, so we should expect the citizens' assembly to be much more motivated to benefit future generations than existing government organs. The motivation comes from the citizens themselves, but it has far fewer obstacles to overcome than the motivation of the electorate.

That said, the literature on assemblies does suggest that participation in assemblies decreases citizen political apathy and increases empathy between deliberation participants, so there could be some salutary motivational effects of citizens' assemblies that we haven't considered here. Moreover, political decisions tend to operate with 2-5 year timelines, and the assembly members will in general live for much longer than this. Given that the citizens' assembly will be deliberative and better-informed than the general public, it is possible that it will function more rationally, seeking to promote the diverse interests of the diverse group of people within the assembly across their lifespans, rather than over the next 2-5 years, and this would significantly decrease short-termism. But this is rather speculative, and the central purpose of the assembly is not to increase this kind of motivation.

Does thinking that the citizen assembly would be effective imply that most government assemblies should be selected by sortition (which, right or wrong, has deployed pretty rarely worldwide)? Or is there something about the future and/or soft-power that makes sortition particularly well suited for this body? (Personally, I like sortition as a governing mechanism in general, but if we can’t get hardly anyone to use it generally, why might they here?)

Sortition has perhaps been deployed less rarely than you think! There have been at least 120 citizens' assemblies and citizen juries deployed worldwide, and sortition is regularly used for the selection of court juries. But it's true that they've rarely been used for the selection of long-lasting government positions.

The role of the citizens' assembly I mentioned above, I think, shows why sortition should be especially helpful here: it removes perverse election incentives to attend to the short-term, and it also reduces the effect of partisan forces, decreasing polarization. These seem especially important when considering long-term issues where our situation is epistemically precarious, but you're right to point out that they are generally very important. I am personally quite open to the idea that a very large proportion of political leaders should be selected randomly. My own dissertation supervisor, Alex Guerrero, is writing an excellent book defending this idea at this very moment.

On why we might be able to get government to use it here: citizens' assemblies have a relatively strong tradition of use for gathering information on the informed views of citizens, and have in the last decade become increasingly popular. As above, I would advocate for greater experimentation with sortition, but they have most popularly been used in citizens' assemblies that are similar to that which we describe, and we expect it to continue to be popular in these institutions.

Will prosperity impact statements obviously improve the long-term future more than it will be used to block/delay projects for near-term reasons? Certainly, environmental impact statements suffer from this problem, and EIS have the advantage that at least there is often some way to objectively check whether they were right or wrong in a reasonable amount of time.

This is the issue raised in the blog post that I find trickiest. It's certainly true that EIAs have frequently been used to block and delay projects on spurious grounds, and the point here that PIAs are less epistemically tractable is spot-on and important. One advantage of PIAs in the legislature is that many more resources can be put to ensuring that they are objective and accurate than can be put into, say, local jurisdictions, given the much greater resources of the federal government and the fewer number of items requiring assessment. An idea we considered but didn't include here is that an independent, non-partisan body such as the in-government research institutions we defend could perform the impact assessments, taking them out of the hands of politicians who might use them for more obstructionist ends. But I remain quite uncertain on the best mechanism for ensuring that PIAs fulfill their information-gathering and soft censure functions rather than becoming used primarily to fuel partisan obstructionism, and I'd certainly be interested in other ideas.