In this 1951 lecture, Heidegger develops the essential continuity of being, building, dwelling, and thinking, and continues his meditation on the thing. Dwelling is now the fundamental ontological structure of being-there, its way of being-in-the-world. It is the manner in which mortals are on the earth and under the sky and exist before the divinities. Dwelling comports two dimensions: mortals are in the fourfold inasmuch as they dwell; and in dwelling they take care of and attend to the entities that they encounter. The basic character of dwelling is to safeguard, to preserve. In dwelling, mortals preserve the fourfold in its essential being, its manner of presencing. In dwelling, mortals take their measure from the way the world fits together or “fugues,” and lets entities show themselves as they are. Dwelling is building a home in the world. Building is being-there’s response to the claim of being, inasmuch as being-there reveals things in their uniqueness and singularity. In thinking, being-there responds to this appeal by trying to commemorate the unconcealment of being and allow its voice to echo. Only in thinking can we become mindful of the difference between being and entities and experience the truth of being.