Heidegger's phenomenology of Dasein, his existential analytic, is the laying bare, or letting be seen, of the fundamental structures of existence – the mode of being peculiar to Dasein. In so far as Dasein is, Dasein exists. But he does not just speak about the structures of existence. He also draws a basic distinction between existing authentically and existing inauthentically. Initially at least, his existential analytic is concerned solely with Dasein in what he calls its ‘everydayness’ (Alltäglichkeit). The structures of being which his phenomenology of Dasein claims to lay bare are, in the first instance, either indifferent to the distinction between authentic (eigentlich) existence and inauthentic (uneigentlich) existence or they are structures of inauthentic existence. So what does this distinction amount to? It first appears in § 4 (though at this stage the terms ‘authentic’ and ‘inauthentic’ are not used): ‘Dasein always understands itself in terms of its existence – in terms of a possibility of itself: to be itself or not itself. Dasein has either chosen these possibilities itself, or got itself into them [in sie hineingeraten], or grown up in them already’ (12). To exist authentically is to be myself, to choose my possibilities of being. The terminology is first used in § 9: ‘And because Dasein is in each case essentially its own possibility this entity can in its being “choose” itself, win itself; it can lose itself or never win itself but only “seem” to.

The being of Dasein is being-in-the-world. Dasein is not a worldless subject. Heidegger now wants to show that Dasein is not an isolated subject. (In fact Dasein is not, strictly speaking, a subject at all.) It is not just a matter of its being the case that I am not the only one of my kind. My being is essentially being-with-others. If this is so then another traditional problem of philosophy, the problem of our knowledge of other minds, turns out to be a pseudo-problem.

The traditional ‘problem’ arises from the assumption that I can only be directly aware of my own mind and its contents. Any knowledge I have of other minds is necessarily indirect. Assuming that it is possible to have knowledge of physical objects through sense-perception, I become aware that some of the physical objects I encounter resemble, both in appearance and behaviour, my own body. On the basis of this resemblance I infer the existence of a mind or consciousness like my own ‘behind’ the other body and its behaviour. The problem with such an analogical inference is that, in the nature of the case, it can only rest on a single case. I cannot use as a premise a generalisation to the effect that whenever I have encountered a body like my own it has been associated with consciousness, because this association is known only in my own case.

The Introduction to Being and Time is preceded by a short piece of text, later referred to by Heidegger as the Foreword, which starts with a quotation from Plato's Sophist. The Eleatic Stranger, a follower of Parmenides and Zeno, is depicted as saying: ‘For manifestly you have long been aware of what you mean when you use the expression “being”. We, however, who used to think we understood it, have now become perplexed.’ Heidegger asks whether we today (he was writing in the 1920s) have an answer to the question of what we mean by the word ‘being’ (seiend) and is emphatic that we do not. And it is not just a matter of being perplexed about the meaning. We lack the understanding for the significance of the question. The task of the Introduction is to reawaken this understanding.

Once this has been done the preliminary aim of Being and Time is the ‘interpretation of time as the possible horizon of any understanding of being’. This already gives us some indication of how we should understand the title of the work. The relationship between being and time is not one of opposition. Rather their relationship is such that the latter is the key to the meaning of the former. However, it will emerge that by ‘time’ Heidegger does not mean what we ordinarily understand by the term.

DISCLOSEDNESS

The impression might have been given that being-in-the-world is simply a matter of dealing with equipment. This can hardly be the case given that being-in-the-world is what is supposed to make any comportment to entities possible. In the Kantian language Heidegger favours, being-in-the-world is a condition of the possibility of comportment to entities as entities. He also comes to identify being-in-the-world with what he calls transcendence. The being of Dasein is transcendence is the sense that Dasein is a going beyond or transcending of what is (Seiendes) to being (Sein). It is in thus transcending entities that Dasein is able to comport itself to entities as entities.

That being-in-the-world is not simply a matter of dealing with equipment becomes clear when we turn to his analysis of being-in. We already know what it is not. But our knowledge of what it is is partial and incomplete. Concern (Besorgen) – engaged having-to-do-with equipment – is at most a way of being-in-the-world. But what being-in-the-world essentially is, is what Heidegger calls disclosedness (Erschlossenheit). Concern is a form of disclosedness in the sense that in our engagement with things, things are disclosed. But it is also a form of disclosedness of Dasein in the sense that Dasein discloses itself to itself in its engagement with things. For reasons of clarity, Heidegger uses the terms ‘uncover’ or ‘dis-cover’ (Entdecken) and uncoveredness or dis-coveredness (Entdecktheit) for the disclosing and disclosedness of entities other than Dasein.

My aim in writing this book is indicated by its title. I have tried to produce an introduction to Being and Time, rather than a page-by-page commentary. As well as being a very difficult book, Being and Time is also a very long book (though only half the length Heidegger originally intended). So it would have been counter-productive to produce an introduction of similar dimensions. What I have attempted to do is to convey the essence of the work, while at the same time attending to its detail. Inevitably I have had to be selective. It has not been my intention to present a particular interpretation of Heidegger (though by its very nature writing about philosophy is interpretive). There are, however, a number of considerations which have guided my approach. At this stage in his philosophical career Heidegger described himself as a phenomenologist. I have found it illuminating to keep in mind the relationship between Heidegger's conception of phenomenology and that of its founder, Husserl (though the main emphasis is on the differences between Husserl's reflective phenomenology of consciousness and Heidegger's hermeneutic phenomenology of what he calls Dasein). I have also been concerned to correct the widespread view that Heidegger is simply an existentialist. While there is no denying the pervasive presence of typically existentialist themes in Heidegger it seems to me that to treat him as simply an existentialist is essentially to trivialise his thought and to fail to recognise its significance in the history of western philosophy.

There are two translations of Being and Time (Sein und Zeit), one by John Macquarrie and Edward Robinson (first published in 1962) and one by Joan Stambaugh (first published in 1996). Both have their merits (the more recent translation is certainly the more readable of the two). For the most part, I have used the older translation (though I have frequently made what I regard as improvements). The Macquarrie and Robinson translation of key terms has become so entrenched in English language discussions of Heidegger that it seemed best to stick with it.

Whereas Husserl's phenomenology is a phenomenology of consciousness, Heidegger's phenomenology is a phenomenology of being. But because being is always the being of beings or entities it is also a phenomenology of entities in the sense that the letting-be-seen of the being of entities can only be achieved on the basis of a clear view of the entities in question. The entity with which Being and Time is principally concerned is Dasein, the entity whose being is such that it involves – indeed is – the understanding of being, its own being and the being of other entities to which it comports itself. Although some entities show themselves naturally and do not need to be made to show themselves, being does not normally show itself. In the analytic of Dasein Heidegger employs the phenomenological method to lay bare the being of Dasein. What is distinctive about Dasein is that in its being it understands being. So the phenomenology of Dasein is seeking to lay bare what is understood in this understanding. The being of Dasein comprises various basic structures, which, because the being of Dasein is existence, Heidegger calls existentials. The most basic of the existentials is being-in-the-world.

THE MEANING OF ‘BEING-IN-THE-WORLD’

The expression is hyphenated to emphasise the unitary character of the phenomenon. But this does not mean that we cannot distinguish and focus on certain constitutive elements. Initially I will focus on two of them: world and in-ness.

In its various modes of comportment to beings or entities – what is – Dasein uncovers (dis-covers, entdeckt) beings or entities. It lets them show themselves. Correlative to the uncovering of entities is the uncoveredness (Entdecktheit) of entities. But such uncoveredness of entities is only possible on the basis of disclosedness (Erschlossenheit) – the disclosedness of world. The disclosedness of world – which is not itself an entity – makes possible both the uncovering and the uncoveredness of entities. Heidegger will argue that these notions are the key to a proper understanding of the nature or essence of truth. This is the topic of § 44 (‘Dasein, Disclosedness and Truth’).

But first we need to say something about what lies behind Heidegger's treatment of this topic and the centrality he gives to it. Why does the topic of truth have such a prominent place in Being and Time? It is a topic which figures in logic but also in epistemology. But fundamental ontology is neither of these things. What does the question of the nature of truth have to do with the question of being? Heidegger begins by pointing out how historically there has been a connection between truth and being. The first discovery of the being of beings by Parmenides ‘identifies’ being with the perceptive understanding (vernehmendes Verstehen) of being. Aristotle defines philosophy as the science of truth but also as the science that considers beings as beings, that is, with regard to their being.

The question of the meaning (Sinn) of being (Sein) is the question which guides everything that is said in Being and Time and which determines the choice of topics to be examined. As we have already indicated, and as the very title of the work suggests, Heidegger thinks that the key to understanding being is time. Properly understood, time is the sense or meaning (Sinn) of being. But the book does not seem to be about being as such but about the being of particular beings or entities. So we have the detailed analyses of the being of those entities Heidegger calls Zeug (equipment): readiness-to-hand (Zuhandenheit); and the somewhat less detailed analyses of the being of things or substances: presence-at-hand (Vorhandenheit). But such analyses are all in the context of the analysis of the being of that entity which I myself am: Dasein. Properly understood, the analyses of readiness-to-hand and presence-at-hand are part of the analysis of the being of Dasein. This is because comportment to entities other than itself and understanding of the being of entities other than itself are integral to the being of Dasein: existence.

Being and Time not only provides an account of the basic structures of the being of Dasein (the existentials); it also claims to provide an answer to the question regarding the sense or meaning of the being of this entity. The being of Dasein is care (Sorge); and the sense or meaning of care is time.

BIOGRAPHICAL NOTE

Martin Heidegger was born on 26 September 1889 in Messkirch, a small town in south-west Germany, about 20 miles north of Lake Constance. From 1903 to 1906 he attended the Gymnasium in Konstanz, having secured a scholarship through Conrad Gröber, the Archbishop of Freiburg, who was also from Messkirch. Although he attended classes at the Gymnasium he lived in a hostel reserved for boys destined for the priesthood. In 1906 he transferred to the Gymnasium and seminary in Freiburg and in 1909 briefly entered the novitiate of the Society of Jesus (the Jesuits). However he left after only two weeks, ostensibly on health grounds. Still with the intention of becoming a priest he enrolled in the theology faculty at the University of Freiburg. Although theology was his main subject he was also required to do some philosophy, though in a form approved by the ecclesiastical authorities. However he had already developed an interest in philosophy independently, specifically in the question which was to dominate his thinking throughout his career – the question of the meaning of being. The first stimulus to this came from the study of a book given to him by Conrad Gröber while he was still attending the Gymasium in Freiburg – Brentano's On the Several Senses of Being in Aristotle. And in his final year at school he came across a work by the Freiburg theologian Carl Braig On Being: A Sketch of Ontology.

The subject matter of Being and Time is being – the being of Dasein and the being of entities other than Dasein to which Dasein comports itself. The method Heidegger employs in what, for a time at least, he called the science of being is phenomenology. We have seen that there are profound differences between Heidegger's conception of phenomenology and that of Husserl. However, despite the differences, it is still possible to see Heidegger's phenomenology as a form of transcendental philosophy. Viewed in this way it would be a radicalisation, rather than a straightforward rejection, of Husserl's transcendental phenomenology. In Heidegger's view it is not enough simply to describe the intentional structures of consciousness in order to be able to see how intentionality, or as he would put it, comportment to entities, is possible. Intentionality must be seen not as a structure of consciousness but as a structure of Dasein, the essence of whose being is the understanding of being. It is the understanding of being which makes intentionality possible. It is Heidegger's concern with the understanding of being as what makes comportment to entities possible which makes it legitimate to see his phenomenology as a form of transcendental philosophy.