If you looked at my positions on the issues, you'd probably call me a progressive. I've worked for years for gay rights and womens rights, even when that work was unpopular, at least in the case of gay rights, within my own party, to say nothing of the country at large. I've organized for, and belonged to, a union for which membership wasn't mandated. I've worked against the self-styled Christian right, worked for immigrant rights as a member a Sanctuary Church in the eighties. I've walked the walk, arguably more than I talk the talk.
On the other hand, I am an unapologetic supporter of fission-based nuclear energy. I'll be glad to support conservation and alternative energy, but I don't think they are solutions to our energy problems. I am an apologetic supporter of better and more efficient meat and milk production methods; I don't care if there's rBST in the milk I get sold, and I don't think it should be labeled as such either way.
I am not a progressive. I am a pragmatic empiricist.
I spent a part of my career as a psychologist -- not a therapist, but the kind of person who studies animal models of cognition. I like to think that I advanced the state of knowledge, and that my studies of the role of the central nuclei of the amygdala in learning will make the world a better place. I won't live long enough to know, though, and, to some extent, it doesn't matter. I've lived the life I've lived, and it has had the effects it has had, and I have no control over anything else.
During that time, I learned a hard lesson about the world: we can measure much more than we like to believe we can. We can't measure "joy", "love", or "hope", perhaps, but we can measure the biochemical correlates thereof. Similarly, we can't measure "hate", "fear", or "disgust", but, yes, we can count, weigh, and measure their biochemical correlates. We can do that so well that we can predict emotional responses on the basis of those metric themselves with high reliability -- and that means that even though we can't measure an animal's soul, we can measure things which tell us a lot about its state.
Now, psychologists and neurobiologists are clever men and women, and they've spent many decades finding these things to measure. But, if you think about it, so are sociologists and economists. Guess what? They measure things, too -- things which reflect the properties of your society, and tell you things about what will happen next. So are engineers and physicists. Now, if I can tell you a lot of inconvenient truths about the way your mind works that you might not like, and certainly wouldn't want to believe about yourself, shouldn't I take the measurements of those other clever people as seriously I would want my own measurements taken?
So, as a consequence of my work, I came to be an political empiricist. If we can measure it, and the measurements don't support my beliefs, then my beliefs are wrong. If I'd rather oppose nuclear energy, I will accept that I'm wrong, simply because the numbers don't add up any other way. If rBST has no measurable effects on milk, then I will oppose stigmatizing its use.
I will not put principle ahead of reality, and, in the modern world, that means I am not a progressive.