Being and Time mentioned in "Being and Time", has been identified by some with Heidegger's central notion of "Sorge" ("cura", care or concern). However, for Heidegger, "theoretical" knowledge represents only one kind of intentional behaviour, and he asserts that it is grounded in more fundamental modes of behaviour and forms of practical engagement with the surrounding world. Whereas a theoretical understanding of things grasps them according to "presence," for example, this may conceal that our first experience of a being may be in terms of its being "ready-to-hand." Thus, for instance, when someone reaches for a tool such as a hammer, their understanding
Being eventually entail the shortening and lengthening of time as well which has never been observed. This logical objection, which was made on Aristotle's argumentation, could not be answered in the ancient times or medieval age, but now it does not sound contradictory to the real nature of Time (as addressed in relativity theory), so by a reverse argument, a philosopher may indeed deduce that everything is changing (moving) even in the deepest core of Being. Although innovated in the late medieval period, Thomism was dogmatized in the Renaissance. From roughly 1277 to 1567, it dominated the philosophic landscape. The rationalist