Summary: Being and Time (page 2)

What Heidegger seeks to revive in this work is a very ancient question, formulated at the very dawn of Greek thought: the question of being.

Already, a few years before Socrates, Parmenides was asking about the difference between being (einai, εἶναι) and non-being in his famous poem.

For example, in this passage:

Come, I shall tell you, and you shall hear,
which are the only paths of inquiry open to the mind:
one, that being is and that non-being is not
– the path of certainty, which goes hand in hand with truth;
the other, that being is not and that non-being somehow is
– a road, I tell you, on which you must by no means let yourself be led.
For you cannot know what is not, you cannot grasp it or speak of it;
for what is thought and what is, are one and the same.¹

Later, Plato takes up this question again, especially in the dialogue of the same name, Parmenides, devoted to the relation between the One and Being, and then in the Sophist, where he examines the links between being and non-being. For example, here:

Let us first be clear about being. Philosophers do not agree on how many beings there are: some admit three, others two, the Eleatics only one; the Muses of Ionia and Sicily claim that being is at once one and many. In truth, we understand being no better than we understand non-being.
Let us question these philosophers. You who claim that the whole is hot and cold, what do you mean by being? Is it a third principle added to the other two? Or do you reserve the name 'being' for one of the two, or for the pair together? But then you are saying that the two are only one.
And you who claim that the universe is one, you say there is only one being. Is this the same thing as the One? Then you are using two names for a single reality. And the whole – do you say that it is other than the One, or that it is identical with it? 'Identical', you will reply. But if it is a whole, it has parts and therefore it is not the One itself, which has no parts; it merely participates in unity. […]
These are inextricable difficulties, and many more would arise for anyone who claimed that being is two, or that it is only one!

Aristotle is a third key thinker of the question of being.

He is in fact the first to conceptualise the discipline that takes being as its object of study—the science of being as being—in this famous passage from the Metaphysics:

There is a science that studies being as being, and also the essential attributes that belong to it as such. This science cannot in any way be identified with the other, so-called particular, sciences, since none of them studies being universally as being; each of them, having carved out a part of being, limits its investigation to the properties that can be observed in that particular part. This is what mathematics does, for example.

Nowadays, we are more likely to speak of 'ontology' to designate this discipline that takes being as its object—a relatively recent term, dating from the seventeenth century.

What we have just sketched is, of course, only a brief overview of the many reflections that have taken being as their object since the dawn of Greek thought.

But it allows us to recall how these three thinkers—Parmenides, Plato, and Aristotle—perform an inaugural act: they raise the question of being.

Yet, according to Heidegger, this question sinks into oblivion at the very moment it is raised.

He holds that as soon as being came into view and was taken as the thematic field of reflection, that reflection lost its way by confusing being with what is—that is to say, with beings.

What does this fundamental distinction refer to?

Just as the act of believing cannot be confused with the believer, or as the act of walking is distinct from the walker, being is different from beings.

This is what we must first become aware of, if the question of being is to appear to us in its own right: being is not the same as beings. What is, is something quite different from the fact of being, and calls for a wholly different kind of thematisation.

Heidegger expresses this with particular clarity in The Basic Problems of Phenomenology, a course given at the University of Marburg a few months after the publication of Being and Time, in which he takes up and develops, often in a more pedagogical way, some of its central themes:

We can always, at any moment and without difficulty, call to mind and bring before us a being belonging to this or that domain. […] A being is something: table, chair, tree, sky, body, words, actions. All that is 'beings'. But being? […] Can we form any representation at all of something like being? Does not anyone who tries to do so feel dizzy? And in fact we are at first at a loss, and grasp only emptiness.

Or again: Ontology—we have said—is the science of being. But being is always the being of a being. By its very essence, being is different from beings. How are we to grasp this difference between being and beings?

This essential distinction between being and beings is what Heidegger calls the ontological difference:

We must be able to mark clearly the difference between being and beings if we are to take something like being as the theme of our research. This is not just any distinction; it is only through this difference that the theme of ontology can be won. We call it the ontological difference—that is, the split between being and beings.

¹ Our translation. The references for the quotations are available in the book Heidegger: A Close Reading