some measure formless before it received its full form, so time was in a manner formless before it was fully formed and distinguished into day and night.
Reply Obj. 3: If the movement of the firmament did not begin immediately from the beginning, then the time that preceded was the measure, not of the firmament's movement, but of the first movement of whatsoever kind. For it is accidental to time to be the measure of the firmament's movement, in so far as this is the first movement.
But if the first movement was another than this, time would have been its measure, for everything is measured by the first of its kind. And it must be granted that forthwith from the beginning, there was movement of some kind, at least in the succession of concepts and affections in the angelic mind: while movement without time cannot be conceived, since time is nothing else than "the measure of priority and succession in movement."
Reply Obj. 4: Among the first created things are to be reckoned those which have a general relationship to things. And, therefore, among these time must be included, as having the nature of a common measure; but not movement, which is related only to the movable subject.
Reply Obj. 5: Place is implied as existing in the empyrean heaven, this being the boundary of the universe. And since place has reference to things permanent, it was created at once in its totality. But time, as not being permanent, was created in its beginning: even as actually we cannot lay hold of any part of time save the "now."
QUESTION 67 ON THE WORK OF DISTINCTION IN ITSELF (In Four Articles) We must consider next the work of distinction in itself. First, the work of the first day; secondly, the work of the second day; thirdly the work of the third day.
Under the first head there are four points of inquiry: (1) Whether the word light is used in its proper sense in speaking of spiritual things?
(2) Whether light, in corporeal things, is itself corporeal?
(3) Whether light is a quality?
(4) Whether light was fittingly made on the first day?
Whether the Word "Light" Is Used in Its Proper Sense in Speaking of Spiritual Things?
Objection 1: It would seem that "light" is used in its proper sense in spiritual things. For Augustine says (Gen. ad lit. iv, 28) that "in spiritual things light is better and surer: and that Christ is not called Light in the same sense as He is called the Stone; the former is to be taken literally, and the latter metaphorically."
Obj. 2: Further, Dionysius (Div. Nom. iv) includes Light among the intellectual names of God. But such names are used in their proper sense in spiritual things. Therefore light is used in its proper sense in spiritual matters.
Obj. 3: Further, the Apostle says (Eph. 5:13): "All that is made manifest is light." But to be made manifest belongs more properly to spiritual things than to corporeal. Therefore also does light.
_On the contrary,_ Ambrose says (De Fide ii) that "Splendor" is among those things which are said of God metaphorically.
_I answer that,_ Any word may be used in two ways--that is to say, either in its original application or in its more extended meaning.
This is clearly shown in the word "sight," originally applied to the act of the sense, and then, as sight is the noblest and most trustworthy of the senses, extended in common speech to all knowledge obtained through the other senses. Thus we say, "Seeing how it tastes," or "smells," or "burns." Further, sight is applied to knowledge obtained through the intellect, as in those words: "Blessed are the clean of heart, for they shall see God" (Matt. 5:8). And thus it is with the word light. In its primary meaning it signifies that which makes manifest to the sense of sight; afterwards it was extended to that which makes manifest to cognition of any kind. If, then, the word is taken in its strict and primary meaning, it is to be understood metaphorically when applied to spiritual things, as Ambrose says (De Fide ii). But if taken in its common and extended use, as applied to manifestation of every kind, it may properly be applied to spiritual things.
The answer to the objections will sufficiently appear from what has been said.
Whether Light Is a Body?
Objection 1: It would seem that light is a body. For Augustine says (De Lib. Arb. iii, 5) that "light takes the first place among bodies."Therefore light is a body.
Obj. 2: Further, the Philosopher says (Topic. v, 2) that "light is a species of fire." But fire is a body, and therefore so is light.
Obj. 3: Further, the powers of movement, intersection, reflection, belong properly to bodies; and all these are attributes of light and its rays. Moreover, different rays of light, as Dionysius says (Div.
Nom. ii) are united and separated, which seems impossible unless they are bodies. Therefore light is a body.
_On the contrary,_ Two bodies cannot occupy the same place simultaneously. But this is the case with light and air. Therefore light is not a body.
_I answer that,_ Light cannot be a body, for three evident reasons.
First, on the part of place. For the place of any one body is different from that of any other, nor is it possible, naturally speaking, for any two bodies of whatever nature, to exist simultaneously in the same place; since contiguity requires distinction of place.
The second reason is from movement. For if light were a body, its diffusion would be the local movement of a body. Now no local movement of a body can be instantaneous, as everything that moves from one place to another must pass through the intervening space before reaching the end: whereas the diffusion of light is instantaneous. Nor can it be argued that the time required is too short to be perceived; for though this may be the case in short distances, it cannot be so in distances so great as that which separates the East from the West. Yet as soon as the sun is at the horizon, the whole hemisphere is illuminated from end to end. It must also be borne in mind on the part of movement that whereas all bodies have their natural determinate movement, that of light is indifferent as regards direction, working equally in a circle as in a straight line. Hence it appears that the diffusion of light is not the local movement of a body.
The third reason is from generation and corruption. For if light were a body, it would follow that whenever the air is darkened by the absence of the luminary, the body of light would be corrupted, and its matter would receive a new form. But unless we are to say that darkness is a body, this does not appear to be the case. Neither does it appear from what matter a body can be daily generated large enough to fill the intervening hemisphere. Also it would be absurd to say that a body of so great a bulk is corrupted by the mere absence of the luminary. And should anyone reply that it is not corrupted, but approaches and moves around with the sun, we may ask why it is that when a lighted candle is obscured by the intervening object the whole room is darkened? It is not that the light is condensed round the candle when this is done, since it burns no more brightly then than it burned before.
Since, therefore, these things are repugnant, not only to reason, but to common sense, we must conclude that light cannot be a body.
Reply Obj. 1: Augustine takes light to be a luminous body in act--in other words, to be fire, the noblest of the four elements.
Reply Obj. 2: Aristotle pronounces light to be fire existing in its own proper matter: just as fire in aerial matter is "flame," or in earthly matter is "burning coal." Nor must too much attention be paid to the instances adduced by Aristotle in his works on logic, as he merely mentions them as the more or less probable opinions of various writers.
Reply Obj. 3: All these properties are assigned to light metaphorically, and might in the same way be attributed to heat. For because movement from place to place is naturally first in the order of movement as is proved _Phys._ viii, text. 55, we use terms belonging to local movement in speaking of alteration and movement of all kinds. For even the word distance is derived from the idea of remoteness of place, to that of all contraries, as is said _Metaph._ x, text. 13.
Whether Light Is a Quality?
Objection 1: It would seem that light is not a quality. For every quality remains in its subject, though the active cause of the quality be removed, as heat remains in water removed from the fire.
But light does not remain in the air when the source of light is withdrawn. Therefore light is not a quality.
Obj. 2: Further, every sensible quality has its opposite, as cold is opposed to heat, blackness to whiteness. But this is not the case with light since darkness is merely a privation of light. Light therefore is not a sensible quality.
Obj. 3: Further, a cause is more potent than its effect. But the light of the heavenly bodies is a cause of substantial forms of earthly bodies, and also gives to colors their immaterial being, by making them actually visible. Light, then, is not a sensible quality, but rather a substantial or spiritual form.
_On the contrary,_ Damascene (De Fide Orth. i) says that light is a species of quality.
_I answer that,_ Some writers have said that the light in the air has not a natural being such as the color on a wall has, but only an intentional being, as a similitude of color in the air. But this cannot be the case for two reasons. First, because light gives a name to the air, since by it the air becomes actually luminous. But color does not do this, for we do not speak of the air as colored. Secondly, because light produces natural effects, for by the rays of the sun bodies are warmed, and natural changes cannot be brought about by mere intentions. Others have said that light is the sun's substantial form, but this also seems impossible for two reasons. First, because substantial forms are not of themselves objects of the senses; for the object of the intellect is what a thing is, as is said _De Anima_ iii, text. 26: whereas light is visible of itself. In the second place, because it is impossible that what is the substantial form of one thing should be the accidental form of another; since substantial forms of their very nature constitute species: wherefore the substantial form always and everywhere accompanies the species. But light is not the substantial form of air, for if it were, the air would be destroyed when light is withdrawn. Hence it cannot be the substantial form of the sun.
We must say, then, that as heat is an active quality consequent on the substantial form of fire, so light is an active quality consequent on the substantial form of the sun, or of another body that is of itself luminous, if there is any such body. A proof of this is that the rays of different stars produce different effects according to the diverse natures of bodies.
Reply Obj. 1: Since quality is consequent upon substantial form, the mode in which the subject receives a quality differs as the mode differs in which a subject receives a substantial form. For when matter receives its form perfectly, the qualities consequent upon the form are firm and enduring; as when, for instance, water is converted into fire. When, however, substantial form is received imperfectly, so as to be, as it were, in process of being received, rather than fully impressed, the consequent quality lasts for a time but is not permanent; as may be seen when water which has been heated returns in time to its natural state. But light is not produced by the transmutation of matter, as though matter were in receipt of a substantial form, and light were a certain inception of substantial form. For this reason light disappears on the disappearance of its active cause.
Reply Obj. 2: It is accidental to light not to have a contrary, forasmuch as it is the natural quality of the first corporeal cause of change, which is itself removed from contrariety.
Reply Obj. 3: As heat acts towards perfecting the form of fire, as an instrumental cause, by virtue of the substantial form, so does light act instrumentally, by virtue of the heavenly bodies, towards producing substantial forms; and towards rendering colors actually visible, inasmuch as it is a quality of the first sensible body.
Whether the Production of Light Is Fittingly Assigned to the First Day?
Objection 1: It would seem that the production of light is not fittingly assigned to the first day. For light, as stated above (A.
3), is a quality. But qualities are accidents, and as such should have, not the first, but a subordinate place. The production of light, then, ought not to be assigned to the first day.
Obj. 2: Further, it is light that distinguishes night from day, and this is effected by the sun, which is recorded as having been made on the fourth day. Therefore the production of light could not have been on the first day.
Obj. 3: Further, night and day are brought about by the circular movement of a luminous body. But movement of this kind is an attribute of the firmament, and we read that the firmament was made on the second day. Therefore the production of light, dividing night from day, ought not to be assigned to the first day.
Obj. 4: Further, if it be said that spiritual light is here spoken of, it may be replied that the light made on the first day dispels the darkness. But in the beginning spiritual darkness was not, for even the demons were in the beginning good, as has been shown (Q. 63, A. 5). Therefore the production of light ought not to be assigned to the first day.
_On the contrary,_ That without which there could not be day, must have been made on the first day. But there can be no day without light. Therefore light must have been made on the first day.
_I answer that,_ There are two opinions as to the production of light.
Augustine seems to say (De Civ. Dei xi, 9,33) that Moses could not have fittingly passed over the production of the spiritual creature, and therefore when we read, "In the beginning God created heaven and earth," a spiritual nature as yet formless is to be understood by the word "heaven," and formless matter of the corporeal creature by the word "earth." And spiritual nature was formed first, as being of higher dignity than corporeal. The forming, therefore, of this spiritual nature is signified by the production of light, that is to say, of spiritual light. For a spiritual nature receives its form by the enlightenment whereby it is led to adhere to the Word of God.
Other writers think that the production of spiritual creatures was purposely omitted by Moses, and give various reasons. Basil [*Hom. i in Hexaem.] says that Moses begins his narrative from the beginning of time which belongs to sensible things; but that the spiritual or angelic creation is passed over, as created beforehand.
Chrysostom [*Hom. ii in Genes.] gives as a reason for the omission that Moses was addressing an ignorant people, to whom material things alone appealed, and whom he was endeavoring to withdraw from the service of idols. It would have been to them a pretext for idolatry if he had spoken to them of natures spiritual in substance and nobler than all corporeal creatures; for they would have paid them Divine worship, since they were prone to worship as gods even the sun, moon, and stars, which was forbidden them (Deut. 4).
But mention is made of several kinds of formlessness, in regard to the corporeal creature. One is where we read that "the earth was void and empty," and another where it is said that "darkness was upon the face of the deep." Now it seems to be required, for two reasons, that the formlessness of darkness should be removed first of all by the production of light. In the first place because light is a quality of the first body, as was stated (A. 3), and thus by means of light it was fitting that the world should first receive its form. The second reason is because light is a common quality. For light is common to terrestrial and celestial bodies. But as in knowledge we proceed from general principles, so do we in work of every kind. For the living thing is generated before the animal, and the animal before the man, as is shown in _De Gener. Anim._ ii, 3. It was fitting, then, as an evidence of the Divine wisdom, that among the works of distinction the production of light should take first place, since light is a form of the primary body, and because it is more common quality.
Basil [*Hom. ii in Hexaem.], indeed, adds a third reason: that all other things are made manifest by light. And there is yet a fourth, already touched upon in the objections; that day cannot be unless light exists, which was made therefore on the first day.
Reply Obj. 1: According to the opinion of those who hold that the formlessness of matter preceded its form in duration, matter must be held to have been created at the beginning with substantial forms, afterwards receiving those that are accidental, among which light holds the first place.
Reply Obj. 2: In the opinion of some the light here spoken of was a kind of luminous nebula, and that on the making of the sun this returned to the matter of which it had been formed. But this cannot well be maintained, as in the beginning of Genesis Holy Scripture records the institution of that order of nature which henceforth is to endure. We cannot, then, say that what was made at that time afterwards ceased to exist.
Others, therefore, held that this luminous nebula continues in existence, but so closely attached to the sun as to be indistinguishable. But this is as much as to say that it is superfluous, whereas none of God's works have been made in vain. On this account it is held by some that the sun's body was made out of this nebula. This, too, is impossible to those at least who believe that the sun is different in its nature from the four elements, and naturally incorruptible. For in that case its matter cannot take on another form.
I answer, then, with Dionysius (Div. Nom. iv), that the light was the sun's light, formless as yet, being already the solar substance, and possessing illuminative power in a general way, to which was afterwards added the special and determinative power required to produce determinate effects. Thus, then, in the production of this light a triple distinction was made between light and darkness.
First, as to the cause, forasmuch as in the substance of the sun we have the cause of light, and in the opaque nature of the earth the cause of darkness. Secondly, as to place, for in one hemisphere there was light, in the other darkness. Thirdly, as to time; because there was light for one and darkness for another in the same hemisphere; and this is signified by the words, "He called the light day, and the darkness night."
Reply Obj. 3: Basil says (Hom. ii in Hexaem.) that day and night were then caused by expansion and contraction of light, rather than by movement. But Augustine objects to this (Gen. ad lit. i), that there was no reason for this vicissitude of expansion and contraction since there were neither men nor animals on the earth at that time, for whose service this was required. Nor does the nature of a luminous body seem to admit of the withdrawal of light, so long as the body is actually present; though this might be effected by a miracle. As to this, however, Augustine remarks (Gen. ad lit. i) that in the first founding of the order of nature we must not look for miracles, but for what is in accordance with nature. We hold, then, that the movement of the heavens is twofold. Of these movements, one is common to the entire heaven, and is the cause of day and night. This, as it seems, had its beginning on the first day. The other varies in proportion as it affects various bodies, and by its variations is the cause of the succession of days, months, and years. Thus it is, that in the account of the first day the distinction between day and night alone is mentioned; this distinction being brought about by the common movement of the heavens. The further distinction into successive days, seasons, and years recorded as begun on the fourth day, in the words, "let them be for seasons, and for days, and years" is due to proper movements.
Reply Obj. 4: As Augustine teaches (Confess. xii; Gen. ad lit. 1, 15), formlessness did not precede forms in duration; and so we must understand the production of light to signify the formation of spiritual creatures, not, indeed, with the perfection of glory, in which they were not created, but with the perfection of grace, which they possessed from their creation as said above (Q. 62, A. 3). Thus the division of light from darkness will denote the distinction of the spiritual creature from other created things as yet without form.
But if all created things received their form at the same time, the darkness must be held to mean the spiritual darkness of the wicked, not as existing from the beginning but such as God foresaw would exist.
QUESTION 68 ON THE WORK OF THE SECOND DAY (In Four Articles) We must next consider the work of the second day. Under this head there are four points of inquiry: (1) Whether the firmament was made on the second day?
(2) Whether there are waters above the firmament?
(3) Whether the firmament divides waters from waters?
(4) Whether there is more than one heaven?
Whether the Firmament Was Made on the Second Day?
Objection 1: It would seem that the firmament was not made on the second day. For it is said (Gen. 1:8): "God called the firmament heaven." But the heaven existed before days, as is clear from the words, "In the beginning God created heaven and earth." Therefore the firmament was not made on the second day.
Obj. 2: Further, the work of the six days is ordered conformably to the order of Divine wisdom. Now it would ill become the Divine wisdom to make afterwards that which is naturally first. But though the firmament naturally precedes the earth and the waters, these are mentioned before the formation of light, which was on the first day.
Therefore the firmament was not made on the second day.
Obj. 3: Further, all that was made in the six days was formed out of matter created before days began. But the firmament cannot have been formed out of pre-existing matter, for if so it would be liable to generation and corruption. Therefore the firmament was not made on the second day.
_On the contrary,_ It is written (Gen. 1:6): "God said: let there be a firmament," and further on (verse 8); "And the evening and morning were the second day."
_I answer that,_ In discussing questions of this kind two rules are to be observed, as Augustine teaches (Gen. ad lit. i, 18). The first is, to hold the truth of Scripture without wavering. The second is that since Holy Scripture can be explained in a multiplicity of senses, one should adhere to a particular explanation, only in such measure as to be ready to abandon it, if it be proved with certainty to be false; lest Holy Scripture be exposed to the ridicule of unbelievers, and obstacles be placed to their believing.
We say, therefore, that the words which speak of the firmament as made on the second day can be understood in two senses. They may be understood, first, of the starry firmament, on which point it is necessary to set forth the different opinions of philosophers. Some of these believed it to be composed of the elements; and this was the opinion of Empedocles, who, however, held further that the body of the firmament was not susceptible of dissolution, because its parts are, so to say, not in disunion, but in harmony. Others held the firmament to be of the nature of the four elements, not, indeed, compounded of them, but being as it were a simple element. Such was the opinion of Plato, who held that element to be fire. Others, again, have held that the heaven is not of the nature of the four elements, but is itself a fifth body, existing over and above these. This is the opinion of Aristotle (De Coel. i, text. 6,32).
According to the first opinion, it may, strictly speaking, be granted that the firmament was made, even as to substance, on the second day.
For it is part of the work of creation to produce the substance of the elements, while it belongs to the work of distinction and adornment to give forms to the elements that pre-exist.
But the belief that the firmament was made, as to its substance, on the second day is incompatible with the opinion of Plato, according to whom the making of the firmament implies the production of the element of fire. This production, however, belongs to the work of creation, at least, according to those who hold that formlessness of matter preceded in time its formation, since the first form received by matter is the elemental.
Still less compatible with the belief that the substance of the firmament was produced on the second day is the opinion of Aristotle, seeing that the mention of days denotes succession of time, whereas the firmament, being naturally incorruptible, is of a matter not susceptible of change of form; wherefore it could not be made out of matter existing antecedently in time.
Hence to produce the substance of the firmament belongs to the work of creation. But its formation, in some degree, belongs to the second day, according to both opinions: for as Dionysius says (Div. Nom. iv), the light of the sun was without form during the first three days, and afterwards, on the fourth day, received its form.
If, however, we take these days to denote merely sequence in the natural order, as Augustine holds (Gen. ad lit. iv, 22,24), and not succession in time, there is then nothing to prevent our saying, whilst holding any one of the opinions given above, that the substantial formation of the firmament belongs to the second day.
Another possible explanation is to understand by the firmament that was made on the second day, not that in which the stars are set, but the part of the atmosphere where the clouds are collected, and which has received the name firmament from the firmness and density of the air. "For a body is called firm," that is dense and solid, "thereby differing from a mathematical body" as is remarked by Basil (Hom. iii in Hexaem.). If, then, this explanation is adopted none of these opinions will be found repugnant to reason. Augustine, in fact (Gen.
ad lit. ii, 4), recommends it thus: "I consider this view of the question worthy of all commendation, as neither contrary to faith nor difficult to be proved and believed."
Reply Obj. 1: According to Chrysostom (Hom. iii in Genes.), Moses prefaces his record by speaking of the works of God collectively, in the words, "In the beginning God created heaven and earth," and then proceeds to explain them part by part; in somewhat the same way as one might say: "This house was constructed by that builder," and then add: "First, he laid the foundations, then built the walls, and thirdly, put on the roof." In accepting this explanation we are, therefore, not bound to hold that a different heaven is spoken of in the words: "In the beginning God created heaven and earth," and when we read that the firmament was made on the second day.
We may also say that the heaven recorded as created in the beginning is not the same as that made on the second day; and there are several senses in which this may be understood. Augustine says (Gen. ad lit.
i, 9) that the heaven recorded as made on the first day is the formless spiritual nature, and that the heaven of the second day is the corporeal heaven. According to Bede (Hexaem. i) and Strabus, the heaven made on the first day is the empyrean, and the firmament made on the second day, the starry heaven. According to Damascene (De Fide Orth. ii) that of the first day was spherical in form and without stars, the same, in fact, that the philosophers speak of, calling it the ninth sphere, and the primary movable body that moves with diurnal movement: while by the firmament made on the second day he understands the starry heaven. According to another theory, touched upon by Augustine [*Gen. ad lit. ii, 1] the heaven made on the first day was the starry heaven, and the firmament made on the second day was that region of the air where the clouds are collected, which is also called heaven, but equivocally. And to show that the word is here used in an equivocal sense, it is expressly said that "God called the firmament heaven"; just as in a preceding verse it said that "God called the light day" (since the word "day" is also used to denote a space of twenty-four hours). Other instances of a similar use occur, as pointed out by Rabbi Moses.
The second and third objections are sufficiently answered by what has been already said.
Whether There Are Waters Above the Firmament?
Objection 1: It would seem that there are not waters above the firmament. For water is heavy by nature, and heavy things tend naturally downwards, not upwards. Therefore there are not waters above the firmament.
Obj. 2: Further, water is fluid by nature, and fluids cannot rest on a sphere, as experience shows. Therefore, since the firmament is a sphere, there cannot be water above it.
Obj. 3: Further, water is an element, and appointed to the generation of composite bodies, according to the relation in which imperfect things stand towards perfect. But bodies of composite nature have their place upon the earth, and not above the firmament, so that water would be useless there. But none of God's works are useless.
Therefore there are not waters above the firmament.
_On the contrary,_ It is written (Gen. 1:7): "(God) divided the waters that were under the firmament, from those that were above the firmament."
I answer with Augustine (Gen. ad lit. ii, 5) that, "These words of Scripture have more authority than the most exalted human intellect.
Hence, whatever these waters are, and whatever their mode of existence, we cannot for a moment doubt that they are there." As to the nature of these waters, all are not agreed. Origen says (Hom. i in Gen.) that the waters that are above the firmament are "spiritual substances." Wherefore it is written (Ps. 148:4): "Let the waters that are above the heavens praise the name of the Lord," and (Dan. 3:60): "Ye waters that are above the heavens, bless the Lord."To this Basil answers (Hom. iii in Hexaem.) that these words do not mean that these waters are rational creatures, but that "the thoughtful contemplation of them by those who understand fulfils the glory of the Creator."
Hence in the same context, fire, hail, and other like creatures, are invoked in the same way, though no one would attribute reason to these.
We must hold, then, these waters to be material, but their exact nature will be differently defined according as opinions on the firmament differ. For if by the firmament we understand the starry heaven, and as being of the nature of the four elements, for the same reason it may be believed that the waters above the heaven are of the same nature as the elemental waters. But if by the firmament we understand the starry heaven, not, however, as being of the nature of the four elements, then the waters above the firmament will not be of the same nature as the elemental waters, but just as, according to Strabus, one heaven is called empyrean, that is, fiery, solely on account of its splendor: so this other heaven will be called aqueous solely on account of its transparence; and this heaven is above the starry heaven. Again, if the firmament is held to be of other nature than the elements, it may still be said to divide the waters, if we understand by water not the element but formless matter. Augustine, in fact, says (Super Gen. cont. Manich. i, 5,7) that whatever divides bodies from bodies can be said to divide waters from waters.
If, however, we understand by the firmament that part of the air in which the clouds are collected, then the waters above the firmament must rather be the vapors resolved from the waters which are raised above a part of the atmosphere, and from which the rain falls. But to say, as some writers alluded to by Augustine (Gen. ad lit. ii, 4), that waters resolved into vapor may be lifted above the starry heaven, is a mere absurdity. The solid nature of the firmament, the intervening region of fire, wherein all vapor must be consumed, the tendency in light and rarefied bodies to drift to one spot beneath the vault of the moon, as well as the fact that vapors are perceived not to rise even to the tops of the higher mountains, all to go to show the impossibility of this. Nor is it less absurd to say, in support of this opinion, that bodies may be rarefied infinitely, since natural bodies cannot be infinitely rarefied or divided, but up to a certain point only.
Reply Obj. 1: Some have attempted to solve this difficulty by supposing that in spite of the natural gravity of water, it is kept in its place above the firmament by the Divine power. Augustine (Gen. ad lit. ii, 1), however will not admit this solution, but says "It is our business here to inquire how God has constituted the natures of His creatures, not how far it may have pleased Him to work on them by way of miracle." We leave this view, then, and answer that according to the last two opinions on the firmament and the waters the solution appears from what has been said. According to the first opinion, an order of the elements must be supposed different from that given by Aristotle, that is to say, that the waters surrounding the earth are of a dense consistency, and those around the firmament of a rarer consistency, in proportion to the respective density of the earth and of the heaven.
Or by the water, as stated, we may understand the matter of bodies to be signified.
Reply Obj. 2: The solution is clear from what has been said, according to the last two opinions. But according to the first opinion, Basil gives two replies (Hom. iii in Hexaem.). He answers first, that a body seen as concave beneath need not necessarily be rounded, or convex, above. Secondly, that the waters above the firmament are not fluid, but exist outside it in a solid state, as a mass of ice, and that this is the crystalline heaven of some writers.
Reply Obj. 3: According to the third opinion given, the waters above the firmament have been raised in the form of vapors, and serve to give rain to the earth. But according to the second opinion, they are above the heaven that is wholly transparent and starless. This, according to some, is the primary mobile, the cause of the daily revolution of the entire heaven, whereby the continuance of generation is secured. In the same way the starry heaven, by the zodiacal movement, is the cause whereby different bodies are