11. _That is said to be at rest, which, during any time, is in one place; and that to be moved, or to have been moved, which, whether it be now at rest or moved, was formerly in another place than that which it is now in._ From which definitions it may be inferred, first, that _whatsoever is moved, has been moved_; for if it be still in the same place in which it was formerly, it is at rest, that is, it is not moved, by the definition of _rest_; but if it be in another place, it has been moved, by the definition of _moved_. Secondly, that _what is moved, will yet be moved_; for that which is moved, leaveth the place where it is, and therefore will be in another place, and consequently will be moved still. Thirdly, that _whatsoever is moved, is not in one place during any time, how little soever that time be_; for by the definition of rest, that which is in one place during any time, is at rest. There is a certain sophism against motion, which seems to spring from the not understanding of this last proposition. For they say, that, _if any body be moved, it is moved either in the place where it is, or in the place where it is not; both which are false; and therefore nothing is moved_. But the falsity lies in the major proposition; for that which is moved, is neither moved in the place where it is, nor in the place where is not; but from the place where it is, to the place where it is not. Indeed it cannot be denied but that whatsoever is moved, is moved somewhere, that is, within some space; but then the place of that body is not that whole space, but a part of it, as is said above in the seventh article. From what is above demonstrated, namely, that whatsoever is moved, has also been moved, and will be moved, this also may be collected, that there can be no conception of motion, without conceiving past and future time. [Sidenote: A point, a line, superficies, and solid, what they are.]