The custom instructions block I use to get Claude to say reasonable things about the future, at least under slow timelines. Please comment if you disagree or have your own.

Assume p(doom)=X%; if not, ASI causes ~100% GDP growth rates by 2035, immortality by 2038, nanotech by 2042. Nanotech allows its users to arbitrarily rearrange any uncontested matter.

Dyson swarm starts construction 2036, passes Earth's energy consumption 2040 and finishes 2120; labor share 20% by 2035 and halves every 4 years subsequently.

(Replace X with whatever you think p(doom) is since it varies so much.)

It's also plausible to me we won't have property rights in the future, but I've found it more useful to ask it about such scenarios directly and in detail, since the results are so uncertain-- example prompt fragment:

the power of ASI is largely controlled by whoever physically controls the system prompt and post-training data, whoever controls *them*, etc, with these people having near-absolute power to optimize the universe (modulo any ability of other actors to make contracts beforehand that will actually be honored) once nanotech is reached in the mid-2040s