Not quite a math post, but related. This summer I've traveled to three continents, attending conferences geared toward pure researchers, math educators and expositors, and mathematicians interested in using computers to advance their research. I have racked up a fair number of frequent flier miles (which I have decided I love). I have spent time away from my family and friends in foreign cultures and familiar cultures. I'm moving to a new position this fall and am preparing for that. In my travels I've spent a lot of time thinking about what shoes to bring and how to build a capsule wardrobe appropriate to the destination. Now I should think about that for the next year!
I've entered a phase of trimming: I have bags of clothes to give to charity and have thrown away many things that I usually hold on to because I'm thrifty and a bit of a packrat. Moving certainly discourages accumulation of stuff.
At the conferences I went to people greeted each other like old friends. Wait, they are old friends. Maybe they only meet up once a year in Madrid or Madison, but if they stay in the mathematical community they may meet up through marriages, divorces, births, deaths, and of course many moves. Mathematics and the mathematical community provide a certain stability. We move for college, grad school, postdocs, professorships, sabbaticals -- I don't think my undergraduate students or "lay people" understand the mobility that is almost required by academic mathematics. (I say almost required because a lucky few stay in one place forever if that's what they want, but if that's what you want you can't be too picky and you may have to sacrifice a lot.)
But you sacrifice a lot either way. I'm moving away from family because I want to try something a bit different and figure out what my place (if any) in academic mathematics could be. What I've tried doesn't fit, and I have the choice of changing myself to fit into an uncomfortable job or uncomfortably following opportunities that may fit better. Sometimes I wonder why I do this. What does it matter? Why should I have any ambition?
In any case, I'm packing.