Of course, society as a whole should (and does) work on both of these things. But one individual can really only pick one to make a sizable impact -- or at the very least, one at a time. Which do you guys think may be more effective to work on?

The core question is: "What kind of impact do you expect to make if you work on either issue?"

Do you think there work to be done in the space of solar power development that other people than yourself aren't effectively doing? Do you think there work to be done in terms of better judgment and decision-making that other people aren't already doing?

we need to develop solar power or whatever else before all the oil and coal run out,

The problem with coal isn't that it's going to run out but that it kills hundred of thousands of people via pollution and that it creates climate change.

I know CFAR is working on that sort of thing, but I'm talking about more genetic or neurological changes)

Why? To me it seems much more effective to focus on more cognitive issues when you want to improve human judgment. Developing training to help people calibrate themselves against uncertainty seems to have a much higher return than trying to do fMRI studies or brain implants.