Martin Heidegger and Jean-Paul Sartre share much in common. In addition to the fact that both were heavily influenced by Edmund Husserl’s phenomenology, while Sartre was a prisoner of war in World War II, he read Heidegger directly, finding much that would later make its way into his own writings. However, despite the similarities, their overall aims (and therefore the arc of their respective philosophies taken as a whole) were very different. This means that these shared themes and concerns sometimes appear with slightly different nuances in the two philosopher’s writings. This article will identify and briefly explore some of these ideas.
Heidegger’s philosophical goal was always singular in nature; the search for the meaning of being. He was questioning being as such, that is, that by which beings appear as beings in the first place, as opposed to the being of beings. This latter, Heidegger saw as merely uncovering what all beings shared in common, thereby never getting beyond beings. Along the way his project would take us through a thorough phenomenological analysis of the being of humans (what Heidegger called Da-sein) and the being of non-conscious objects, but his goal was always to transcend this level of analysis in search of a deeper, more mysterious quarry; being itself.
Sartre’s goal, by comparison, was relatively straightforward. He wanted to describe the different ways things could be in the world. His conclusion was there are two fundamental modes of being; being-for-itself (consciousness) and being-in-itself (non-conscious things) and his entire book is essentially a phenomenological exploration of these two ways of being. Sartre undoubtedly goes into more detail than Heidegger concerning the precise nature of human consciousness and our relations with other human consciousnesses (being-for-others) but in keeping his attention where he did, he ended up with a much more subjectivist and, by Heidegger’s standards, less foundational account of being.
Although both philosophers use the term ‘being’, they end up using it in very different ways. As mentioned, ‘Being’ for Heidegger refers to that which allows beings to appear, the source of meaningful presence (anwesen) in the world. This will obviously include conscious human beings (Da-sein) in some way, but also go beyond them.
In his later writings, Heidegger would characterise Being as the event of the appropriated clearing. Briefly, ‘event’ indicates that Being is an active process. It doesn’t describe a thing, a supreme being, for example. The ‘clearing’ is Da-sein as the site where beings first appear as beings, and where ‘when’ and ‘where’ first attain meaning. ‘Appropriated’ refers to the way that Da-sein has been taken up by Beyng, in order to bring about the revelation of beings. This means that giving meaning to reality (causing beings to appear as the beings they are) isn’t something that human beings do, it’s something that happens to us. The reason is that before the event of Being, there are no beings (including that of the human variety) to do anything. When human beings first give meaning to the world, they have already been thrown into it, indicating that they couldn’t have been the ‘thrower’. The event happens to Da-sein, but also needs Da-sein to happen. This is what Being means for Heidegger.
Although Sartre starts out following a similar path, it quickly becomes clear that his understanding of being is quite different. For him, being is simply ontology. What is. As I have outlined above, Sartre divided the world into two realms of ontology; being-for-itself and being-in-itself, but it isn’t quite this simple. As Sartre talks about the for-itself, we see that while it is indispensable in creating the world (a reality imbued with meaning and significance), it isn’t actually a thing. Instead, it is a perspective on things. He talks about consciousness being intentional, that is, always consciousness of something. Consciousness, in itself, has no content. It is what it intends, and nothing more (literally – we’ll talk about nothingness later). This means, strictly speaking, it isn’t. Ultimately then, Sartre uses the word ‘being’, as what is, to refer only to being-in-itself since the for-itself has no independent, substantial existence. Indeed, he will even come to define the for-itself as a modification of the in-itself.
Facticity actually has two meanings in Heidegger. First, he uses it to describe human existence, not as Da-Sein (the way we exist as sense-makers of the world), but as something objectively present; that is, as mere objects. Second, and more importantly for Heidegger, facticity describes one aspect of the being of Da-Sein; specifically, that aspect which roughly corresponds to the temporal past, or the way Da-Sein is always already thrown into a world which he/she did not make and which is already full of relevance and meaning that he/she didn’t give it. This temporal dimension to facticity as thrownness is crucial for the Heidegger of Being and Time because in that book he was seeking to ground the being of Da-Sein in the three ek-stases of Temporality; projection, making present, and having-been (the sources of our ‘vulgar’ understanding of time as future, present, and past).
Sartre’s use of ‘facticity’ is similar although he goes into more detail and whereas we saw Heidegger emphasise the past, Sartre emphasises the objective dimension of human existence. The being of human existence is consciousness, or the for-itself (which is absolutely free given Sartre’s paradoxical but intriguing description of consciousness as being what it isn’t and not being what it is), but this evanescent, content-less, fluid mode of being is also necessarily haunted by that mode of being that is fixed; i.e. the in-itself (the being of things, which, in contradistinction to humans, are what they are). This in-itself aspect of human being manifests in the contingent physicality (objective presence in Heideggerian terms) that is the human body. The past is also a part of facticity for Sartre but only in the sense that existence requires a physical locus. Facticity derives from this core in-itself dimension of the for-itself and it ultimately features more in Sartre’s philosophy as the brute facts which accompany human existence and which resist our freedom (although he is clear they don’t actually limit our freedom in any way).
Of course, freedom arises for Da-Sein in the sense that any of a number of possible projects in the future are open to us and we are free to project ourselves into any of them. However, Heidegger never attempts to justify this against the claims of determinism and he doesn’t really dwell much on this notion of freedom. I suspect he wouldn’t be particularly interested in this metaphysical debate.
There is another, more important, sense in which freedom appears in Being and Time though; namely, freedom understood in relation to authenticity. Da-Sein is originally in the world in an inauthentic mode of being, which means that the meanings we give to things, events, and actions are meanings we haven’t deliberately chosen for ourselves. Rather, we have inherited them from other people, people Heidegger collectively calls Das Man, through customs, social mores, traditions, etc. We do things this way because that is the way they do them. We say this or that because that is what they say. In overcoming this (and also accepting the inevitability of our death), Da-Sein frees itself to live authentically. This is really the main way freedom enters into B&T.
By contrast, in Being and Nothingness Sartre was completely absorbed by the endeavour to defend and preserve the absolute freedom of the for-itself. To safeguard freedom, Sartre explicitly argues against determinism in Being and Nothingness. There are two things he says to refute determinism. First, he appeals to the nature of the for-itself. Only things which are what they are (the in-itself) can be determined. They are a “plenitude of being”, fixed and whole as what they are, completely free of any lack or negation. The for-itself (consciousness), on the other hand, is transcendent; it is never what it is because it always, and necessarily, exists at a remove from itself. Being conscious of myself means I can never completely coincide with that self; rather than being a self, I am presence to self. Similarly, causes never fully determine me the way they do the in-itself because in being conscious of those causes, I transcend them, escaping them by my very existence.
Secondly, after our discussion of facticity one might think that these brute facts constrain or reduce our freedom in some way. Sartre denies this. He doesn’t see facticity as a limitation on our freedom because it is only in the face of facticity that we can exercise freedom in the first place. In fact, this points the way to a deeper truth. It is only by being in a (factical) situation with all its attendant difficulties and obstacles that freedom arises, but the opposite is also true; the situation (and its difficulties and obstacles) only gets its meaning through the freedom that the human being is. Brute facts lack meaning until the for-itself bestows meaning upon them.
For Heidegger, nothingness (the complete negation of the totality of beings) is apprehended in anxiety, which is a sense of unease not about this or that being, but about beings as a whole. In anxiety, we are anxious but we don’t know what we are anxious about because the feeling (which Heidegger calls ‘mood’ or ‘attunement’) is a profound indifference before all beings (i.e. existence itself).
What do we grasp then when we apprehend the nothing? Certainly not an object, a something, which could hardly then be nothing. We have seen that the experience of nothing is one in which beings as a whole lose all significance, they are in “retreat as a whole”. Heidegger’s insight here is that, rather than being a purely negative or destructive act, this nihilation of beings as a whole (the nothing) is actually what allows beings to exist in the first place, that is, “as what is radically other – with respect to the nothing.” Nothingness, far from being an empty logical concept or the opposite of being, turns out to lie at the heart of Being itself; i.e. that by which beings appear as beings in the first place.
In B&N Sartre launches his own investigation into nothingness; an investigation which nevertheless very closely parallels the one Heidegger embarked on in What is Metaphysics? Sartre’s account however, is narrower in scope and concludes by uncovering a much more subjective origin of nothingness.
He begins by noting that we are “encompassed with nothingness”. Perception affords us a simple example of this; the cup on my desk is not that book, I am not that cup. These negative judgements, being the explicit rejection of being, cannot therefore arise from pure being; i.e. the in-itself. That leaves consciousness, or the for-itself, as the source of negation. As I’ve already hinted at, for Sartre, the for-itself is nothingness itself. It isn’t a substance, a nugget, of something; instead, it is “lightness and translucency”, a modification of the in-itself which introduces nothingness into the world, but a modification that isn’t anything in-itself. Nothingness, for Sartre lies at the heart of being-in-itself, as the for-itself.
Heidegger doesn’t really explore the mitdasein (with-Dasein), our relation with other people, other Da-sein, in any great depth. This is because Heidegger’s project involves Dasein coming to an appreciation of Being, as an individual. Heidegger’s writings are replete with references to authenticity being something the individual must undertake alone and the call of conscience coming only to the individual. Still, we share the world with other people, in such a way that simply encountering things unavoidably directs us to them. Being-with features in Heidegger in two ways; concern and Das Man.
Concern is the way we relate to other people and its two positive extremes are “taking away care” and “giving back care”. The former is a leap in for the other, which displaces him/her so that they became dependent and therefore dominated. The latter is a leap ahead of the other, which helps him/her to understand their being in an authentic manner. The other aspect of being-with, Das Man, we have already encountered in the section on freedom.
Sartre took our being-for-others to a whole new level with a detailed phenomenological dissection he called ‘concrete relations with others’ in which he adopted the Hegelian master-slave model. For Sartre, the Other is an invading presence, a free consciousness which always transcends my own freedom, a foreign source of meaning in the world which I am unable to grasp and reduce to something in my world. Because my world is disrupted by this alien meaning-giving, the encounter with the Other, is inevitably one driven by conflict.
The conflict manifests in the attempt to reduce the Other to an object for me (as subject), thereby possessing, and nullifying, their freedom. If I can succeed in this, the threat the Other poses to my absolute freedom disintegrates. I subsume them in my world. The problem, of course, is that at the same time, the Other is also trying to reduce me to an object for them. This struggle underlies all of the relationships we form with other people, including love and desire. The irony in this conflict is that possession of the Other’s freedom is ultimately impossible precisely because a subjective freedom, by its nature, is ungraspable. This obviously renders all social interaction essentially futile.
‘Guilt’ in Heidegger is an existential concept which, since it is simply a part of what it means to be a human being, therefore has nothing to do with the moral sense of guilt one feels at having done something wrong. ‘Guilt’ in this sense then is our culpability for introducing negation into the world; that is, for being the ground of a nullity, the ground for a being which is determined by a not. With this definition in place, there are two senses in which Da-sein is guilty. The first has to do with its being thrown; the second, with the way it projects into possibilities.
Da-sein is guilty first because it exists but had no control over that existence. We are never existent before our ground. This means that as soon as we exist, and could therefore take full responsibility for something (in this case, our existence), we are already too ‘late’. This condition of human existence Heidegger calls thrownness and our guilt here is the “nullity of being-the-ground”. Da-sein is also guilty in a second sense because, as a continual projecting into possibilities, it is constantly not projecting into other possibilities. This is the nullity in the “structure of being of projecting”. Taking these two aspects of guilt together, Da-sein is the null ground of a nullity, and guilt therefore pervades human existence prior to any actions we take.
Sartre, on the other hand, talks about guilt in connection with our being-for-others. Recall that our relations with others centre around a struggle to possess the Other as an object. From this original relation, Sartre says we are guilty in two ways. First, when we are forced to assume responsibility for our own objectivity under the gaze of the Other, and secondly, when we constitute the Other as an object and instrument.
This first assertion might sound odd. Why should I be guilty for the Other objectifying me? You aren’t guilty for the Other’s action, your guilt arises because you exist but no longer ground that existence. The Other, in making you an object, in subsuming your freedom under theirs, has defined your existence, and yet you must ‘exist’ that existence, as if it were yours. In essence, you take on your existence without being the ground of that existence. Conversely (and more straightforwardly), in the second instance, you are guilty for reducing the Other to an object, thereby forcing them to experience that same alienation from their own existence.
As with Heidegger, we can never be absolved of this guilt, no matter how nicely we resolve to treat other people. Whatever you may decide to do for the Other in their capacity as a free subject, your every effort must necessarily end up positing their freedom as a transcendence-transcended. The original sin, as Sartre colourfully describes it, is simply to exist in a world with others.
Death represents something of a problem for phenomenology simply because the experience of death is, by definition, the end of all experience. However, Heidegger devises an ingenious approach to this limit situation. Since death isn’t something that is added to or taken away from Da-sein, he reasons its death must already be accounted within its being, as a not-yet. Just as Da-sein is its not-yet (its ultimate possibility) as long as it is, it also always already is its end, not as a being-at-an-end of Da-sein, but as a being-toward this end.
Since we can’t grasp death as one of our possibilities (because, unlike other possibilities, it is never realised by existent Da-sein) but we also can’t grasp it apart from our possibilities (because it is, nevertheless, Da-sein’s ultimate possibility), Heidegger concludes it must indirectly manifest in our relation to all of our possibilities. As a fundamental aspect of our being, death must pervade every aspect of our lives and indeed, it does. Although we tend to think of death as something that will happen one day in the distant future, the truth is it is an ever-present possibility which could be realised in any moment. In this sense, an unavoidable part of human existence is being-toward-death. To the extent that we have internalised this, we are able to live authentically.
Sartre explicitly rejects Heidegger’s highly individualised and personal account of death as a possibility I exist towards, insisting it is an always possible nihilation of my possibles which therefore lies outside my possibilities. One of the core structures of the for-itself is the way it transcends its past towards its future possibles. Death, in denying us the future, expressly removes meaning from life. In light of this, death is absurd. Where Heidegger posits death as something we exist towards, Sartre treats it as the exact opposite; i.e. facticity. Death, in ending all possibility, brings the for-itself to a close, locks it in being. It is then, the occurrence by which the for-itself becomes in-itself.
There is another interesting element to death for Sartre, which appears in his description of it as the “triumph of the point of view of the Other”. After death; i.e. after the passing of the consciousness who was able to recover, and exert control over, his or her meanings through the various specific projects he or she undertakes, this being, or this life, can now only derive meaning from the Other, who has become free to pass judgement on it, however he or she wishes. Death is a total dispossession effected by the Other. In light of these considerations, death, rather than belonging to the ontological structure of the for-itself, actually points to the in-itself and the Other.
The above is by no means an exhaustive comparison of these two existentialist thinkers. In truth, I have barely scratched the surface of a subject that could easily fill a book (and has already slipped about fifteen hundred words above respectable blog-post size, my apologies for that, but also my sincere thanks if you made it this far).
Although Sartre and Heidegger do sometimes traverse the same ground (unavoidable considering the relationship to each other and to previous philosophers), they deviate from each other much more frequently. The interesting thing though is that these deviations; rather than amounting to core differences in their ultimate philosophies, more often than not, end up complementing the other. It therefore, isn’t so much a case of having to work out who was right, as it is one of piecing them together to get a more complete picture of human existence.
 There is actually a third way of being, being-for-others, but rather than being a fundamental mode of being, this is more a modification of being-for-itself.
 Sartre actually calls this the transphenomenal being of the perceiver.