the so and so large. Motion is determined as the amount of motion, and, similarly, mass is determined as weight.
6. Therefore, the difference between natural and against nature, i.e., violent, is also eliminated; the βία, violence, is as force only a measure of the change of motion and is no longer special in kind. Impact, for instance, is only a particular form of impressed force, along with pressure and centripetality.
7. Therefore, the concept of nature in general changes. Nature is no longer the inner principle out of which the motion of the body follows; rather, nature is the mode of the variety of the changing relative positions of bodies, the manner in which they are present in space and time, which themselves are domains of possible positional orders and determinations of order and have no special traits anywhere.
8. Thereby the manner of questioning nature also changes and, in a certain respect, becomes the reverse.
We cannot set forth here the full implications of the revolution of inquiry into nature. It should have become clear only that, and how, the application of the First Law of Motion implies all the essential changes. All these changes are linked together and uniformly based on the new basic position expressed in the First Law and which we call mathematical.
E. The Essence of the Mathematical Project [Entwurf]*
(Galileo's Experimental with Free Fall)
For us, for the moment, the question concerns the application of the First Law, more precisely, the question in what sense the mathematical becomes decisive in it.
How about this law? It speaks of a body, corpus quod a viribus impressis non cogitur, a body which is left to itself. Where do we
* Perhaps the best insight as to what Heidegger means by Entwurf is Kant's use of the word in the Critique of Pure Reason. "When Galileo experimented with balls whose weight he himself had already predetermined, when Torricelli caused the air to carry a weight which he had calculated beforehand to be equal to that of a definite column of water, or, at a later time, when Stahl converted metal into lime and this again into metal by withdrawing something and then adding it, a light broke in on all investigators of nature. They learned that reason only gains insight into what it produces itself according to its own project [was sie selbst nach ihrem Entwurfe hervorbringt]; that it must go before with principles of judgment according to constant laws, and constrain nature to reply to its questions, not content merely to follow her leading-strings" (B XIII).—Tr.