My lectures are published and not published; they will be intelligible to those who heard them, and to none beside.

[T]he ancient philosophers... all of them assert that the elements, and those things which are called by them principles, are contraries, though they establish them without reason, as if they were compelled to assert this by truth itself. They differ, however... that some of them assume prior, and others posterior principles; and some of them things more known according to reason, but others such as are more known according to sense: for some establish the hot and the cold, others the moist and the dry, others the odd and the even, and others strife and friendship, as the causes of generation. ...in a certain respect they assert the same things, and speak differently from each other. They assert different things... but the same things, so far as they speak analogously. For they assume principles from the same co-ordination; since, of contraries, some contain, and others are contained.

[U]niversal is known according to reason, but that which is particular, according to sense...

[T]hey pronounce absurdly who thus speak, as the Pythagoreans assert: for at the same time they make the infinite to be essence, and distribute it into parts.

[B]ecause that which is finite is always bounded with reference to something... it is necessary that there should be no end... [N]umber also appears to be infinite, and mathematical magnitudes, and that which is beyond the heavens. And since that which is beyond is infinite, body also appears to be infinite, and it would seem that there are infinite worlds; for why is there rather void here than there? ...If also there is a vacuum, and an infinite place, it is necessary that there should be an infinite body: for in things which have a perpetual subsistence, capacity differs nothing from being. The speculation of the infinite is, however, attended with doubt: for many impossibilities happen both to those who do not admit that it has a subsistence, and to those who do. ...It is ...especially the province of a natural philosopher to consider if there be a sensible infinite magnitude.

Since the science of nature is conversant with magnitudes, motion, and time, each of which must necessarily be either infinite or finite...[we] should speculate the infinite, and consider whether it is or not; and if it is what it is. ...[A]ll those who appear to have touched on a philosophy of this kind... consider it as a certain principle of beings. Some, indeed, as the Pythagoreans and Plato, consider it, per se, not as being an accident to any thing else, but as having an essential subsistence... the Pythagoreans... consider the infinite as subsisting in sensibles; for they do not make number to be separate; and they assert that what is beyond the heavens is infinite; but Plato says that beyond the heavens there is not any body, nor ideas, because these are no where: he affirms, however, that the infinite is both in sensibles, and in ideas. ...Plato establishes two infinities, viz. the great and the small.

[I]t is impossible for motion to subsist without place, and void, and time.

Since... nature is a principle of motion and mutation... it is necessary that we should not be ignorant of what motion is... But motion appears to belong to things continuous; and the infinite first presents itself to the view in that which is continuous. ...[F]requently ...those who define the continuous, employ the nature or the infinite, as if that which is divisible to infinity is continuous.

According to one mode... nature is thus denominated, viz. the first subject matter to every thing which contains in itself the principle of motion and mutation. But after another mode it is denominated form, which subsists according to definition: for as art is called that which subsists according to art, and that which is artificial; so likewise nature is both called that which is according to nature, and that which is natural. ...that which is composed from these is not nature, but consists from nature; as, for instance, man. And this is nature in a greater degree than matter: for every thing is then said to be, when it is form in energy... entelecheia, rather than when it is incapacity.

[A]ll things as subsist from nature appear to contain in themselves a principle of motion and permanency; some according to place, others according to increase and diminuation; and others according to change in quality. Book II, Ch. I, p. 88.