Heidegger on the Ubiquity of Philosophy

Philosophy is around humans day and night like the sky and the earth, almost even closer than they are, like the brightness that rests between them, which humans almost always overlook since they are only busy with what appears to them within the brightness. Sometimes, whenever it darkens, humans become especially attentive to the brightness around them. But even then, humans do not pay closer attention to it, because they are accustomed to the fact that the brightness returns.