Yesterday's post, by the way, was not meant in much seriousness. That is, it was perfectly accurate, but it was not a plea for sympathy. It was simply the quickest thing to post in response to a complaint that I hadn't been posting.
Over the past few weeks I have gotten a great deal of advice on my topic, some of it solicited and some of it not. Most of it has not been particularly useful, because every person brings with them a set of assumptions about how a dissertation should be done. But the way person A does a dissertation has so much less in common with the way person B does a dissertation that it's not useful. It's like telling a baseball player, "Now, get back in the game, and I really want to see you running with the ball." Now you might expect that this comes from friends and family who know only a little about getting a PhD, but it comes from faculty as much as anyone.
Before I started a PhD, I assumed that all dissertations (within one field, at least) would pretty much be the same. At the very least, there was some bar of quality that every dissertation had to meet. I quickly learned otherwise. Essentially, every doctoral student who reaches the point of defending a proposal can complete a dissertation if one can motivate oneself to do it. The committee won't stand in the way. Faculty have very different expectations for students, based on their assessment of the student's capabilities and career goals. I'm not going to get into whether that's fair; it's just the way it is.
Faculty also don't agree on how to approach the topic. One professor told me it didn't matter what topic I picked; the important thing was to pick the quickest thing I could and go get a job. Another told me the topic was the most important part of the dissertation; this person had chosen something they really weren't interested in, and it had taken years to shake off the association with it that they were growing sick of.
Finally, there are considerations of departmental politics that constrain me in ways people outside the department would have no reason to be aware of. Topic X or Approach Y simply aren't on the table if I want the backing of my faculty.
I'm in the department I'm in, so there's nothing I can do about that last point. When I chose my committee, and in particular my advisor, though, I made a commitment to approaching the topic and methods in a certain way. I chose to play baseball instead of football, so to speak. Yet when football-approach professors suggest something, they assume I'm playing the same game they are, even when they know who my coach is. Finally, regarding the level of expectations, at this point it is always possible to lower them, but not so much to do the reverse.
The point is that the most well-meaning (and even very expert) advice really isn't helpful here. The only people who are much help are my committee, and even they can't pick a topic for me. (Actually, they could. Asking them to do so would be the quickest way to lower expectations.) And I've been talking to people and bouncing things off of them, thinking it would help me, and it hasn't much. I appreciate everyone's willingness to help, of course, but in the end they've been better for moral-building than practical solutions. That's how it's supposed to be, I guess, at least in the social sciences. One student, going mano a mano against the void to wrestle something out of it.