"Man is Spirit. But what is Spirit? Spirit is the Self. But what is the Self? The Self is a relation that relates itself to itself; or it is, in this relation, that which relates it to itself (the Self is not the relation, but that the relation relates itself to itself)."First we might want to cut through the jargon of the first few sentences: what Kierkegaard wants to say is that the interesting or important thing about human beings is that they have a self. To have a self is to be a special sort of thing. Stones don't have a self. Artifacts, such as chairs and tables don't have a self. Plants don't have a self, and most animals don't either. But human beings have a self, and that is so essential to them that Kierkegaard straightforwardly identifies being human with having a self. It's what Man is — having a self.
Kierkegaard, The Sickness Unto Death
The thesis of The Sickness Unto Death is that almost every self that is in fact out there, that is, almost every human being's self in the world, past and present, is defective. A self that is fully in order is very rare; the typical condition of selves is to be defective. The defect takes various forms, but there is a collective term that is used throughout the book for them: Despair. Despair is a condition we're all in (or, at any rate, most of us are in); it's the name for that pervasive defectiveness of selves. Thus, in order to explain what Despair is, it's necessary for Kierkegaard to first state what a self is, for only then we can understand in what sense and in which ways such a self may be defective. That's the point of giving a definition of a self.
So now we have seen what the definition is for and what (intuitively) it is targeted at. We have some idea, that is, what we're talking about, what will be defined for us now. (It's only to be expected, of course, that our idea of a self will be changed in the process of understanding the definition. Part of the point of giving a definition is to clarify and sharpen our understanding of what's defined, and another part is to connect the idea of what is defined in the definition to other ideas. So we learn about distinctions and about connections to other concepts, and that will transform our overall view of things, including the thing that's talked about in the definition.)
|Mariana Varela, Inextricable|
Now let's sort this out carefully. I can have an attitude towards something. For instance, I can have an attitude to this armchair: that I find it inviting. I feel somewhat lazily drawn towards it, I imagine that it would be pleasant to be seated in it right now, and so on. I have an attitude of finding the armchair inviting.
Attitudes can be to objects like an armchair, or to other people, but I can also have an attitude towards myself. I might reflect, right now, and find that my attitude towards the armchair (my finding it inviting) reveals something about me, at least about what I am right in this moment, right in taking this attitude (of finding the armchair inviting). I take myself to be lazy, let's say. Now I'm taking an attitude towards myself, the attitude of taking myself to be lazy (in finding the armchair inviting).
Assume, for a moment, that this sort of episode happens frequently: I consider myself lazy quite often; and not only when faced with armchairs I find inviting; let's say I'm also reluctant to get out of bed each morning; I'm constantly drawn to over-extend my lunch break; I'm hesitant to go out in the evenings for my sheer inertness, and so on. Let's assume, for a moment, thus, that I'm a generally lazy person. In the episode described above, when considering myself lazy when finding the armchair inviting, I recognize an instance of my general laziness. In other words, I relate my attitude towards myself (my considering myself lazy) to other, similar attitudes I have registered in the past. In so relating my attitude, I give meaning to the predicate 'lazy' by putting my attitude towards myself in a class of related attitudes (which would fall under the same predicate). Thus what I do isn't just taking an attitude towards myself, it's also an attitude that contains a further reflective self-reference (in putting itself, as it were, in the category of being an attitude of laziness).
Let's now drop the assumption I've made in the previous section: that episodes like the one described (episodes of considering myself lazy) happen frequently. Let's instead assume that such episodes have never happened before at all. The new assumption thus is the first time ever that I consider myself lazy, in finding this armchair inviting; moreover, this is indeed the first time (we now assume) that I consider myself lazy at all.
Note that we have two options here:
i) It's in fact the first time that I could consider myself lazy; it's the actual first time in my life ever that I had occasion for it; never before was I in a situation where some attitude I took towards something (armchair or other) gave me the opportunity to consider myself lazy.
ii) Although in fact I had many episodes of attitudes towards external things already, the thought hasn't so far crossed my mind to consider myself lazy; only now this has occurred to me, for the first time.
In either case I can either become aware that I'm lazy or be aware that I've become lazy. (That is, we have four cases here: first, that I get into such a situation for the first time but take myself to have been in it for longer and assume that I've just become aware of the fact; second, that again I'm in the situation for the first time and also think of myself as having come into it for the first time; third, that I've actually been there before and now correctly but for the first time notice it; and finally fourth, that I've been in that situation before but got aware of it only now and thus take it, incorrectly, to be the first time.)
In any of these cases again I'm not just taking an attitude towards myself, but also an one that includes that additional reflective self-reference (putting the attitude itself in the category of being an attitude of laziness, one that I think of as either just having come about or just having come to my awareness). So it's not just an attitude, but it also brings with it a comparison with attitudes (that were taken or not, in which they at least might have been taken) at earlier times. These additional reflective self-references (that they are self-references of the attitudes themselves) make up what we call the self. Or, to put it differently, you're said to have a self only if your attitudes include some of that rather complicated variety. And that means that in some way or other, your past attitudes are built into your self. This build-up of reality on unreality is again a form of what I've called sedimentation.
 Perhaps there will be rather sophisticated artifacts at some future time which will have a self; think of a supercomputer with an 'intelligent persona' here, one which starts developing its own thoughts, goals and so on. Perhaps that sort of being will have a self in the relevant sense then. But as of today, that's still firmly an idea from the realm of science fiction, even though some progress towards it has been made in the branch of science and technology known as Artificial Intelligence. So for the moment, artifacts don't have a self, even if in principle they might, and in the future they possibly will, have one.
 Recent research, especially on primates, more and more suggests that we should ascribe a self in the relevant sense to at least some animal species, which again shows that there's no absolute gap between humans and other beings with respect to having a self: it's something that we might in principle share with animals and machines; though (to repeat) it is still not fully settled whether in fact, and at present, we do. And even if so, there are still obvious large differences in degree with respect to how far developed these selves are, and thus we have to be careful not to be carried away with conclusions from such findings. (A caution which, alas, many science journalists and some popularizing scientists have long thrown overboard, which will probably not help improving the image of science in the long run.)
 The plan of Kierkegaard's author (the book is written under a pseudonym, and that is always relevant with Kierkegaard; so I'll not assume from the beginning that we're discussing Kierkegaard's text, but one that he puts before us as the work of an author who is himself already a character) is to explore the concept of Despair. I've capitalized the word to indicate that Despair, Kierkegaard's term, is potentially different in meaning from the everyday word. It's a central term, and it takes much of the book to explain what is to be understood by it. (And this being philosophy, of course, it's not simply settled; part of the challenge is always to interpret central concepts such as this one, so in a sense there is no fixed meaning at all for the term. We always have to keep in mind its interdependency and interaction with our interpretation of the book which discusses it.)
Kierkegaard's Despair is a defect in the Self. Before his author starts exploring the nature of this defect, its various forms of appearance, and the meaning of the fact (which he claims is a fact, anyway) that this defect pervades our reality and is a defect to be diagnosed in pretty much everybody's Self — before he starts discussing all this, he tells us what a Self is, so that we can understand the idea of a defective Self. It's a compressed passage and so obscure and complicated that some commentators have thought that it isn't even part of the more serious work but rather a playful, parodistic introduction (satirically imitating the jargon of another philosopher, namely Hegel). I don't think that's likely, though, so I'll just take it seriously, and take it to be doing what it purports to be doing, namely: defining what it means to be a Self (so that we later on can learn what it means to have a defective Self, i.e. what it means to be in Despair). For me, of course, the interest is mereley whether we can learn something interesting about any of the forms of unreality from all this.