Simon Critchley, The Guardian, Monday 22nd June, 2009.
I talked in my first blog entry about Heidegger's attempt to destroy our standard, traditional philosophical vocabulary and replace it with something new. What Heidegger seeks to destroy in particular is a certain picture of the relation between human beings and the world that is widespread in modern philosophy and whose source is Descartes (indeed Descartes is the philosopher who stands most accused in Being and Time). Roughly and readily, this is the idea that there are two sorts of substances in the world: thinking things like us and extended things, like tables, chairs and indeed the entire fabric of space and time.
The relation between thinking things and extended things is one of knowledge and the philosophical and indeed scientific task consists in ensuring that what a later tradition called "subject" might have access to a world of objects. This is what we might call the epistemological construal of the relation between human beings and the world, where epistemology means "theory of knowledge". Heidegger does not deny the importance of knowledge, he simply denies its primacy. Prior to this dualistic picture of the relation between human beings and the world lies a deeper unity that he tries to capture in the formula "Dasein is being-in-the-world". What might that mean?
If the human being is really being-in-the-world, then this entails that the world itself is part of the fundamental constitution of what it means to be human. That is to say, I am not a free-floating self or ego facing a world of objects that stands over against me. Rather, for Heidegger, I am my world. The world is part and parcel of my being, of the fabric of my existence. We might capture the sense of Heidegger's thought here by thinking of Dasein not as a subject distinct from a world of objects, but as an experience of openedness where my being and that of the world are not distinguished for the most part. I am completely fascinated and absorbed by my world, not cut off from it in some sort of "mind" or what Heidegger calls "the cabinet of consciousness".
Heidegger's major claim in his discussion of world in Being and Time is that the world announces itself most closely and mostly as a handy or useful world, the world of common, average everyday experience. My proximal encounter with the table on which I am writing these words is not as an object made of a certain definable substance (wood and iron, say) existing in a geometrically ordered space-time continuum. Rather, this is just the table that I use to write and which is useful for arranging my papers, my laptop and my coffee cup. Heidegger insists that we have to "thrust aside our interpretative tendencies" which cover over our everyday experience of the world and attend much more closely to that which shows itself.
The world is full of handy things that hang together as a whole and which are meaningful to me. In even more basic terms, the world is a whole load of stuff that is related together: my laptop sits on my desk, my spectacles sit on my nose, the desk sits on the floor, and I can look over to the window at the garden and hear the quiet hum of traffic and police sirens that make up life in this city. This is what Heidegger calls "environment" (Umwelt), where he is trying to describe the world that surrounds the human being and in which it is completely immersed for the most part.
Heidegger insists that this lived experience of the world is missed or overlooked by scientific inquiry or indeed through a standard philosophy of mind, which presupposes a dualistic distinction between mind and reality. What is required is a phenomenology of our lived experience of the world that tries to be true to what shows itself first and foremost in our experience. To translate this into another idiom, we might say that Heidegger is inverting the usual distinction between theory and practice. My primary encounter with the world is not theoretical; it is not the experience of some spectator gazing out at a world stripped of value. Rather, I first apprehend the world practically as a world of things which are useful and handy and which are imbued with human significance and value. The theoretical or scientific vision of things that find in a thinker like Descartes is founded on a practical insight that is fascinated and concerned with things.
Heidegger introduces a distinction between two ways of approaching the world: the present-at-hand (Vorhandenheit) and the ready-to-hand (Zuhandenheit). Present-at-hand refers to our theoretical apprehension of a world made up of objects. It is the conception of the world from which science begins. The ready-to-hand describes our practical relation to things that are handy or useful. Heidegger's basic claim is that practice precedes theory, and that the ready-to-hand is prior to the present-at-hand. The problem with most philosophy after Descartes is that it conceives of the world theoretically and thus imagines, like Descartes, that I can doubt the existence of the external world and even the reality of the persons that fill it – who knows, they might be robots! For Heidegger, by contrast, who we are as human beings is inextricably bound up and bound together with the complex web of social practices that make up my world. The world is part of who I am. For Heidegger, to cut oneself off from the world, like Descartes, is to miss the point entirely: the fabric of our openedness to the world is one piece. And that piece should not be cut up. Furthermore, the world is not simply full of handy, familiar meaningful things. It is also full of persons. If I am fundamentally with my world, then that world is a common world that experienced together with others. This is what Heidegger calls "being-with" (Mitsein)