Lecture 8 — Why, in mutual generation and corruption, there, is sometimes absolute generation and qualified corruption, and conversely.

The cause implied in this solution must no doubt be considered adequate to account for coming-to-be and passing-away in their general character as they occur in all existing things alike. Yet, if the same process is a coming-to-be of this but a passing-away of that, and a passing-away of this but a coming-to-be of that, why are some things said to come-to-be and pass-away without qualification, but others only with a qualification? The distinction must be investigated once more, for it demands some explanation. (It is applied in a twofold manner.) For (i) we say 'it is now passing-away' without qualification, and not merely 'this is passing-away': and we call this change 'coming-to-be', and that 'passing-away', without qualification. And (ii) so-and-so 'comes-to-be-something', but does not 'come-to-be' without qualification; for we say that the student 'comes-to-be-learned', not 'comes-to-be' without qualification.

(i) Now we often divide terms into those which signify a 'this somewhat' and those which do not. And (the first form of) the distinction, which we are investigating, results from a similar division of terms. For it makes a difference into what the changing thing changes. Perhaps, e.g. the passage into Fire is 'coming-to-be' unqualified, but 'passing-away-of-something' (e.g. Earth): whilst the coming-to-be of Earth is qualified (not unqualified) 'coming-to-be', though unqualified 'passing-away' (e.g. of Fire). This would be the case on the theory set forth in Parmenides: for he says that the things into which change takes place are two, and he asserts that these two, viz. what is and what is not, are Fire and Earth. Whether we postulate these, or other things of a similar kind, makes no difference. For we are trying to discover not what undergoes these changes, but what is their characteristic manner. The passage, then, into what 'is' not except with a qualification is unqualified passing-away, while the passage into what 'is' without qualification is unqualified coming-to-be. Hence whatever the contrasted 'poles' of the changes may be whether Fire and Earth, or some other couple—the one of them will be 'a being' and the other 'a not-being'. We have thus stated one characteristic manner in which unqualified will be distinguished from qualified coming-to-be and passing-away: but they are also distinguished according to the special nature of the material of the changing thing. For a material, whose constitutive differences signify more a 'this somewhat', is itself more 'substantial' or 'real':

while a material, whose constitutive differences signify privation, is 'not real'. (Suppose, e.g. that 'the hot' is a positive predication, i.e. a 'form', whereas 'cold' is a privation, and that Earth and Fire differ from one another by these constitutive differences.)

The opinion, however, which most people are inclined to prefer, is that the distinction depends upon the difference between 'the perceptible' and 'the imperceptible'. Thus, when there is a change into perceptible material, people say there is 'coming-to-be'; but when there is a change into invisible material, they call it 'passing-away'. For they distinguish 'what is' and 'what is not' by their perceiving and not-perceiving, just as what is knowable 'is' and what is unknowable 'is not'—perception on their view having the force of knowledge.

Hence, just as they deem themselves to live and to 'be' in virtue of their perceiving or their capacity to perceive, so too they deem the things to 'be' qua perceived or perceptible—and in this they are in a sense on the track of the truth, though what they actually say is not true.

Thus unqualified coming-to-be and passing-away turn out to be different according to common opinion from what they are in truth. For Wind and Air are in truth more real more a 'this somewhat' or a 'form'—than Earth. But they are less real to perception which explains why things are commonly said to 'pass-away' without qualification when they change into Wind and Air, and to 'come-to-be' when they change into what is tangible, i.e. into Earth.

We have now explained why there is 'unqualified coming-to-be' (though it is a passing-away-of-something) and 'unqualified passing-away (though it is a coming-to-be-of-something). For this distinction of appellation depends upon a difference in the material out of which, and into which, the changes are effected. It depends either upon whether the material is or is not 'substantial', or upon whether it is more or less 'substantial', or upon whether it is more or less perceptible.

58. Having resolved the question which he had introduced concerning the continuity of generation, the Philosopher here proceeds to resolve the question principally intended. About this he does two things:

first, he raises the question;

second, he solves it, at now we often divide terms (318a35; [59]).

He says therefore first (318a25) that we must investigate once more why some things are said to be generated and corrupted absolutely and others not, in keeping with what was said in the determination of the preceding question, namely, that the generation of this is the corruption of that, and the corruption of this is the generation of something else. For this seems to require some explanation, for, from the fact that things are mutually generated and corrupted, there would seem to be the same reason explaining the absolute generation and corruption of one and the other, For we say in things that are not generated one from the other that something is corrupted absolutely, and not merely this, i.e., in the qualified sense and not absolutely. For example, we say that one who is learning is indeed becoming a knower, and this is to become in a qualified sense; nevertheless he does not become absolutely, because he was existing absolutely before he was a knower. Consequently, attention must be paid to both: namely, as to why, in the case of things being generated one from another, some are said to be cases of absolute generation and others of generation in a qualified sense; and as to why this distinction also prevails in things that are not generated one from another.

59. Then, at now we often divide terms (318a35), he answers this question.

First, in the cases where things are generated one from another;

second, in the cases where things are not so generated, at but why are some things (319a3; [67]).

About the first he does two things:

first he answers the question;

second, he summarizes, at the distinction here (319a11; [68]).

Regarding the first he proposes three ways according to which, in things that are generated one from another, it happens that there is generation and corruption of one absolutely and of the other in a qualified sense.

With respect to the first way (318a35) he says that, as has been determined many times, some things that are described affirmatively signify a this something, i.e., a certain being, while some signify non-being. And this accounts for the present question, namely, why some things are said to be generated and corrupted absolutely and others in a qualified sense. For in this matter the difference depends on that into which a thing is changed through generation and corruption. For example, if we should follow the opinion of Parmenides and say that fire is being and earth non-being, then a change heading toward fire (for example, if from earth fire is generated) will be called generation absolutely (because it is headed toward being) but not corruption in the strict sense, but rather corruption of this, i.e., of earth, which is a non-being. Conversely, the generation of earth will be a certain generation, but not absolute generation, because it is the generation of non-being; but it will be absolute corruption, because it is the corruption of being, namely, of fire. Thus, indeed, did Parmenides posit two principles of things, namely, being and non-being, calling fire "being" and earth "non-being." Perhaps a reason was that among the other elements fire possesses more form and earth less.

This example, however, is not according to the opinion of Aristotle, who considered both to be being—therefore, he adds that whether one supposes such examples or others makes no difference as far as the proposition is concerned. For we are concerned, when we introduce examples, with the manner and not the subject, i.e., not worrying whether it is actually the case in these terms, or in any others. On this account, in the books on logic also, he uses examples according to the opinions of other philosophers, but they are not to be introduced as though they were the words of Aristotle. Therefore from what has gone before, this much should be gathered, that absolute corruption is that which tends toward non-being absolutely, and absolute generation that which tends toward being absolutely. Therefore, let what has been said about absolute or qualified generation and corruption be considered as determined, whether in fire and earth, or in any other terms, provided they be so related that one is being and the other non-being, as if we should "living" and "dead," or anything else of the sort.

He concludes therefore that there is one way in which absolute generation and corruption differ from non-absolute.

60. But it seems that this is not a suitable difference. For the road to absolute non-being, which he says is absolute corruption, cannot be understood as leading to what is absolutely nothing—since every natural corruption comes about by something being resolved into some certain matter. Similarly, absolute non-being cannot be understood as pure privation without form—since matter is never divested of every form, so as to be under privation only. Therefore, the non-being into which simple corruption tends must be understood as a privation joined to some form. Now privation is conjoined to every natural form in things that can be generated and corrupted. Consequently, in those things which are mutually generated and corrupted, one thing will not be said to be more generated or corrupted absolutely than another.

Therefore, it should be said that absolute non-being is here understood to mean matter with the privation joined to some form. Form, however, is of two kinds: one is perfect and completes the species of a natural thing, as in the case of the form of fire or water or man or plant; the other is an incomplete form which neither perfects any natural species nor is the end of the intention of nature, but is something on the road to generation and corruption. For it is plain in the generation of composites, for example, of an animal, that between the principle of generation, which is the seed, and the ultimate form of the complete animal, there are many intermediate generations (as Avicenna says in his Sufficiency) which have to be terminated to certain forms, none of which makes the being complete in species, but rather an incomplete being which is the road to a certain species.

Likewise, on the side of corruption there are many intermediate forms that are incomplete: for the body of an animal is not, as soon as the soul is separated, immediately resolved into the elements; rather this takes place by means of many intermediate corruptions in which many imperfect forms succeed one another in the matter, such as the form of a dead body, then the form of a putrefied body, and so on. When, therefore, through corruption a privation is reached that is joined to such a form in matter, there is absolute corruption in the strict sense; when, from the privation to which is attached an imperfect form which was the road to generation, there is arrival at the complete form, there is absolute generation.

61. Then, at while a material (318b16), he mentions the second way and says that in another way there will be a certain generation which is not absolute, no matter what the matter, that is, even if that into which there is corruption has a certain nature, provided it have some defect. For a thing whose [specific] differences signify more a "this something," is more a substance; while a thing whose [specific] differences signify more a privation is more a non-being: for example, "hot" is a certain predicament, i.e., something affirmative, without a privation, and it is a species, i.e., a form, while coldness is a privation. Now it is by these differences that earth and fire differ, for earth is naturally cold, and fire naturally hot. Therefore, fire is more substance, and earth approaches more to non-being.

62. First one must consider why coldness is here called a privation, since cold and hot are contrarily opposed, and both of two contraries are a certain nature; otherwise, they would not be in the same genus, for privation and non-being are not in any genus. To this it must be said that, as was shown in Metaphysics X, the opposition of privation and having is the basis for the opposition of contraries. Consequently, one contrary is always by way of defect and a certain privation with respect to the other. Therefore coldness is called a privation, not because it is a pure privation, such as to be blind or naked, but because it is a quality that is defective with respect to heat. Hence, in this the present way differs from the first—for the first way was based on the difference between being and non-being absolutely, while the present way is based on the difference between perfect and imperfect being.

Second, it is necessary to consider how it may be said here that earth and fire differ with these differences, namely, in terms of cold and hot. For this must be understood of substantial differences — otherwise they would not pertain to generation and corruption, but rather to alteration. Now the principles of substantial differences, which are constitutive of species, must be substantial forms, which are specific. According to this, therefore, it follows that heat and cold are the substantial forms of fire and earth. This is wholly impossible.

This is so, first of all, because it is not possible that the same thing be in one thing an accident and in another a substantial form, unless one speak equivocally. But hot and cold are accidents in other bodies, to which they are referred univocally the same as to the elements, from the admixture of which such qualities are found in them [i.e., in the other, composite, bodies]. Therefore it is not possible that hot and cold in the elements be substantial forms.

Second, this is so because no substantial form is per se perceptible to sense; but to the intellect alone, whose object is the what something is, as is said in On the Soul III. The forms that are per se perceptible to sense are qualities of the third type, called for this reason, passible, since they cause passions in the senses, as is said in the Predicaments. Since, therefore, the heat of fire and the cold of earth or water are perceptible to sense, they cannot be substantial forms.

One should say, therefore, that, as is had in Metaphysics VIII, substantial differences, when unknown, are manifested by accidental differences—consequently we frequently use accidental differences in place of substantial. And it is in this way that the Philosopher here says hot and cold to be the differences of fire and earth. For hot and cold, since they are proper passions of these bodies, are the proper effects of the substantial forms of the same. Consequently, just as other intelligible causes are made known through sensible effects, so by the perfection of the hot and the imperfection of the cold we judge that the substantial form of fire is more perfect than the substantial form of earth. For all substantial forms differ according to more and less perfect—hence in Metaphysics VIII there is stated that the species of things are as numbers, whose species vary according to addition and subtraction.

Likewise, one could doubt his statement that in the case of the thing whose difference signifies to a greater degree a "this something," such a thing is substance to a greater degree—since he says in the Predicaments that substance is not susceptible of "more" and "less." This should be answered by saying that he does not mean to signify increase and remission of substance in the predicament of substance, but a greater or lesser perfection in the species of substance according to the aforesaid difference of forms.

63. He gives the third way at the opinion, however (318b18), in regard to which he does three things:

first, he presents the manner according to which some explain the difference between generation and corruption absolutely and in the qualified sense;

second, he shows that they are mistaken, at we have now explained (318b33);

third, he compares this third way with the second, at the distinction here (319a11).

He says therefore first (318b18) that it seems to many that absolute and qualified generation differ rather in terms of being more or less perceptible to sense, than according to perfection and imperfection of differences, as was explained in the second way. For they say that when something is changed into matter that is easy to sense, then something is generated absolutely—for example, when something is changed into earth or into water; but when something is changed into what is not manifest to sense, e.g., into air, they call this absolute corruption. And he introduces their reason, which was that they determined something to be being and non-being on the basis of whether it is sensed or not sensed, considering only what is sensed to be being. This is because, for them, there is no difference between sense and intellect, as certain ones laid down, and as is stated in On the Soul III. Consequently they use sense observation as though it had the force of intellectual science, which has in some sense a capacity for all things. Hence the knowable is being, and the unknown, non-being.

64. Then, at hence, just as they deem (318b24), he shows the falsity of this opinion. And he says that such men, just as they considered animals to live and exist, because they actually sense or can sense, so they also supposed things to exist because they are sensed or can be sensed—as though sense were the perfection of the sensible thing, just as it is the perfection of the one sensing. And in this they in a certain way pursued and destroyed the truth of things. For since something is said to be true from the fact that it is, then, if the being of things consisted only in being sensed, there would be no truth in things but only in the one sensing them. However, it is not true that no truth is in things. Hence in removing the truth of things, they assert something not true.

65. Then, at thus unqualified coming-to-be (318b27), he compares this way with the second and says that absolute generation and corruption differ as considered according to opinion, which pertains to this third way, and according to the truth, which the second way touches. For spirit, i.e., wind, and air are less according to sense, that is, judging the being of a thing from its being sensed. And therefore, whatever things are corrupted absolutely, are said to be, according to the third way, corrupted into things that are not sensed, and to be generated absolutely when they are changed into something that can be touched and felt, as when they are changed into earth. But in reality the contrary happens. For air is more a "this something" and a species than earth, and more perfectly a being. Therefore, according to truth there is more of an absolute generation if from earth air is produced than conversely.

66. Then, at we have now explained (318b33), he summarizes what has been said, and says the cause has been stated why one type of generation is absolute, although it be the corruption of something, and why one type of corruption is absolute, although it be the generation of something. For these differ by reason of the matter, i.e., by reason of that into which something is changed through generation or corruption: either because it is substance, i.e., being, or non-being, as was explained in the first way; or because this is more and that not, because, namely, one is more perfect being than the other, which pertains to the second way; or because the matter from which and into which something is changed is more sensible or less sensible, which pertains to the third way. By matter he here means, not pure matter, but the thing from which something is generated or into which it is corrupted.