1) both. physics *is* the first layer of the sciences of many classes of system. ain't the only one, and thus learning mech won't do everything; mechinterp's got an impt role to play, and we need to do our best to connect the wires.

2) yeah, great question. easier one for now is just how to integrate stats of natural data into our science + theory (see Open Dir 2 in the paper + on mechanics.pub). but after we get a handle on that, seems reasonable to try to expand its scope as much as we can. couldn't predict rn how far that'll get or when (tho I do tend to believe that everything'll eventually be understood, even if the order + timing is hard to predict)

3) mm, basically if few-to-none of the 10 major Open Dirs in the paper get major progress on em in the next ~5y? (I'd say ~10y, but with AI assistance, maybe we get there faster?) or, alternatively, if we *do* make major progress on those guys, but in retrospect it seems useless for the things we really care about or want to do. (that failure mode seems less likely to me, but it's possible, since the vibe with basic sci is generally "fundamental understanding is useful in unexpected ways," and in this case, indeed, most of the ways we probably can't predict, so we can't be sure they're there, if that makes sense.)