There is a difference between how things are and how they should be. What I mean is not the obvious, that things (generally speaking) are not how they should be, but that the question 'how are things?' is a different kind of question to the question 'how should things be?'
In philosophical terminology, 'how are things?' is an empirical question - it seeks information about the world, and is answered by using our senses, our scientific methods, and so on. 'How should things be?' is what we call 'normative'. For present purposes, though, I'll refer to this divide as the practice/principle divide; this can be made explicit by extending the two questions into 'How are things, in practice?' and 'How should things be, in principle?', both of which are relatively familiar from an idiomatic point of view.
Philosophy is preeminently the study of questions of principle. It may - indeed, should - take account of matters of practice, because principles that turn out to be irrelevant to the world aren't much good to anyone, but a philosophical analysis is an analysis of principles, and the skills that ten years of studying philosophy equips one (specifically, me) with are the skills of this kind of analysis. It's not a subject aimed at establishing how things are, or even about predicting how things will be.
Why bring up this distinction? Well, in the first place, I've had several brangles with people over the life of this blog, both here and elsewhere, because we were unclear which side of the principle/practice divide we were talking about. Most people, quite rightly, think in terms of practice first. From the perspective of actually living, it is less essential to think about principle, but that doesn't mean it's not important to have some people who think about principles - which is what I try to specialise in.
The particular reason and context for talking about this now is that the distinction neatly characterises the responses I got to my blog post last month about privacy. In that post, I asked for reasons to be concerned about violations of my privacy. I (quite deliberately) didn't make a principle/practice distinction; I wanted both kinds of reasons.
I got some very interesting practice-based reasons, and I am now less complacent than I was about practical matters of privacy. But I got no response based on a general principle. The closest I got was the point that the specific case of PRISM clashes with the principle of the rule of law, because the US government is supposed to be bound by the 4th Amendment, which PRISM clearly violates (thanks to Rafe for this point). That's entirely correct and I agree wholeheartedly, but because it refers to a specific case, it's still a point of practice rather than principle. The question of principle would be 'Is the 4th Amendment justified?'
A common theme among the practice-based answers I got was, in a way, principle-directed, in that it asked 'If there was no principle of privacy, where would infringements of privacy stop?'. An example of this is the question 'Would you still not object if the government put a camera in your bedroom?', the implicit point being that this is surely something that would make me object on privacy grounds.
It's true that I would feel deeply, powerfully self-conscious and uncomfortable with a camera in my bedroom. But, to turn this into something that is truly a question of principle, we can ask whether I should feel uncomfortable in this way. I am uncomfortable with my own body, to be sure, and don't really like having other people see it (even relatively commonly-exposed bits of it, like my arms - and it's very rare to see me in shorts or with bare feet), but this is because of a whole bunch of negative messages society is throwing at me, possibly combined with a pathological psychological condition or two.
I like to believe that, were all those factors removed (none of which I consider to be essential to who I am, so we're not talking about changing me in anything I consider to be a significant way), I would be entirely happy to be seen naked. I would like to believe, perhaps even, that I could be proud of my body, and thus untroubled by the idea of a camera recording me getting dressed or whatever.
The 'What about a camera in your bedroom?' question gets its emotive force from the fact that many of us are ashamed of at least something that such a camera would record - whether it's getting undressed, or dancing around the bedroom in our underwear, or watching My Little Pony, or whatever. But we can argue that this shame is a result of an unjust stigmatisation, and that (so long as they are not harmful), the things that we do for pleasure/fun should, in principle, never be subjects for shame. If you love My Little Pony, it should be a subject for pride, a part of your identity, rather than something you dislike about yourself.
The really interesting question, from a principled point of view, is whether you can ever do something you're proud of and still want it kept private. I think I'm going to have to split this topic there, though, and tackle the link between secrecy and privacy separately.
Let me be clear about one thing: the fact that there is a question of principle hanging over privacy does not invalidate practice-based arguments for privacy. In particular, it doesn't invalidate democratic decisions; if most people still want privacy, our governments ought to be legally bound to uphold it, because the principle of the rule of law is very clearly desirable, and that means democratic governments doing what their people want.
If we do, in our next installment, conclude that there isn't a principled ground for privacy, then we can still say that privacy is a temporary necessity, and the need for it a symptom of a deeper illness (society's tendency to shame and stigmatise, or even outright punish, certain activities and kinds of activities). The situation is analogous to going to war - we abhor, from a principled point of view, the killing and destruction, but we must sometimes cause some killing and destruction (so the theory behind military responses goes, at least) to prevent greater atrocities.
I'm not saying we should all happily install cameras in our bedrooms tomorrow. I'm just saying that the question of why we shouldn't has a deeper answer than the purely emotional one.