the mode of being of Dasein, existence, is essentially determined by being-in-the-world. "World" is that particular whole toward which we comport ourselves at all times. The personal relation of one existence to another is also not a free floating cognitive relation of an I -self to a thou-self, as if they were isolated souls; but rather each is a factical self in a world, and the being of the self is essentially determined by its comportment to this world.
By contrast, a material thing—a rock or any item for use, like a chair—has no world; its mode of being is devoid of any comportment toward a world. This kind of being is merely extant. What is extant is of course one of those beings toward which we can comport ourselves. This being may be extant within our world, it may belong to what we come across in the world and be an innerworldly being; but it does not have to be that way. When we say about a being that it is innerworldly—like nature, for example—this being still does not have the mode of being which comports itself toward a world; it does not have the mode of being of being-in-the-world. It has the mode of being of extantness, to which additionally the determination of innerworldliness can accrue when a Dasein exists which lets that being be encountered as innerworldly in Dasein's being-in-the-world. Physical nature can only occur as innerworldly when world, i.e., Dasein, exists. This is not to say that nature cannot be in its own way, without occurring within a world, without the existence of a human Dasein and thus without world. It is only because nature is by itself extant that it can also encounter Dasein within a world.
For an initial orientation regarding the structure of Dasein and being-in-the-world, let us keep in mind the explicit difference between human beings and rocks. Rocks have no world; humans are affected by a world toward which they comport themselves. With this rough differentiation we are still far from a genuine philosophical understanding. In the course of interpretation of the Critique, we shall see how the very basic difficulties of the Kantian problematic are grounded in Kant's failure to recognize the phenomenon of world and to clarify the concept of the world-something that neither he nor his successors did.
We deliberately overlooked plants and animals in our preliminary characterization of being-in-the-world. Animals are not extant like rocks, but they also do not exist in the manner of comporting themselves to a world. Nevertheless in plants and animals we find a kind of orientation toward other beings which in a certain way surround them. As distinguished from the extantness of material things and from the existence of humans, we call the mode of being of plants and animals: life. To be sure, we speak of the animal's environment, but the question here is what "" world" means and whether, strictly speaking, we can talk about ~~world'' here. For what we mean by world is intrinsically connected to