Intelligence, reason, opinion and sense

Timaeus: "The former of these, indeed, is comprehended by intelligence in conjunction with reason, since it always subsists with invariable sameness. But the latter is perceived by opinion, in conjunction with irrational sense, since it is generated and corrupted, and never truly is."
 

perpetual being	is comprehended by intelligence in conjunction with reason
that which is generated	is perceived by opinion in conjunction with irrational sense

   For these definitions, however, it is usual to accuse Plato, in the first place, indeed, that he does not assume genus, as the rules of definitions require. In the next place, that he does not manifest what the nature is of the things defined, but distinguishes them by our knowledge. It is necessary, however, prior to this habitude, to consider things themselves by themselves. 
   But [in defence of Plato] we shall demonstrate the very contrary, viz. that those who are accustomed thus to doubt perfectly err. For what kind of genus has a place in being, which comprehends every intelligible essence? For if essence has no genus prior to itself, nor definition, since it is most generic, what can you say respecting being which is comprehensive of every essence, and of all powers and energies? 
   Neither, therefore, is being the genus of eternal being: for if it was, it would not be simply being, but a certain being. Nor is non- being the genus of eternal being lest we should ignorantly make eternal non-being. For every where genera are predicated of species. Hence, there is not a genus of being. 
   Besides, is not a definition derived from knowledge adapted to theory, and to the proposed definitions? For if, as we said before, Plato wished to use these axioms and hypotheses in the demonstrations which he intended to make, it was necessary that they should be known and manifest to us. 
   If, indeed, he had exhorted us to investigate the nature of things, itself in itself, he would have ignorantly filled the whole of his doctrine definitions with obscurity.
   But as he wished to make known through definitions being and that which is generated, he produced the demonstrations through things that are known, and clearly represents to us the peculiarity of them, in order that being excited and perfected, we may more manifestly survey what each of them is. 
   For since every thing gnostic, is either the thing known itself, or perceives, or possesses the thing known; for intellect, indeed, is the intelligible, but sense perceives what is sensible, and dianoia possesses in itself the dianoetic object; and as we are not naturally adapted to become the intelligible, but know it through the power in us which is conjoined with it; this being the case, we require this power, and through this the nature of being is known to us. After this manner, therefore, we answer the doubts.

   It is requisite, however, to observe how Plato proposing to himself the problems, renders each of them manifest, both affirmatively and negatively. But giving an answer to each, in perpetual being, indeed, he assumes the affirmative alone, but in that which is generated, the negative, adding to it also, "and which is destroyed." 
   He, also, explains the words, "but which is never being," through the assumption of, "never truly is." For since being is characterized by existence alone, but that which is generated by non-existence, he assumes the one, alone defining it, and says, subsisting invariably the same; but he assumes the other together with negation, yet not with negation alone, because definitions respect affirmations, and signify that which in each thing is inherent.
   It is not, however, wonderful, if he not only says "which is generated," but also, "and corrupted." For as he adds to being, the words "subsisting with invariable sameness," and not only says, it is always; so likewise to that which is generated he adds, "and corrupted." For this so far as it is generated, is different from perpetual being; but so far as it is corrupted, it differs from that which is invariably the same. For that which is generated, so far as it is generated and corrupted, is incapable of connecting itself; since if it were, it would also be able to produce itself. 
   Assuming therefore each by itself, i.e. being and that which is generated, he assumes the former as that which is above generation, but the latter, as that which is not indestructible. So that when the representation of being accedes to that which is generated, it is able after a certain manner to abide in a condition of always becoming to be.

   Let us however, consider each of the words by itself, through which he composes the propositions; and in the first place, let us see in how many ways intelligence subsists, and collect by a reasoning process the other progressions of it. 
   The first intelligence therefore, is the intelligible, which passes into the same with the intelligible, and is not any thing different from it. This also is essential intelligence, and essence itself, because every thing in the intelligible subsists after this manner, viz. essentially and intelligibly. 
   The second intelligence is that which conjoins intellect with the intelligible, possessing a peculiarity which is connective and collective of the extremes, and existing as life and power, filling indeed intellect from the intelligible, but establishing it in the intelligible. 
   The third is the conjoined intelligence in a divine intellect itself, being the energy of intellect, through which it comprehends the intelligible it contains, and according to which it intellectually perceives, and is what it is. For this intelligence is energy, and intelligence itself, but is not intelligible intelligence. Nor does it exist as power, but (as we have said,) as energy, and intellectual intelligence. 
   The intelligence of partial intellects has the fourth order. For each of these possesses this and entirely contains in itself a certain conjoined intelligible and intelligence. Or rather each has all these partially, viz. intellect, intelligence, and the intelligible, through which also it is conjoined to total intellects, intellectually perceives each of these, and likewise the whole intelligible world. 
   The fifth intelligence is that of the rational soul. For as the rational soul is called intellect, thus also the knowledge of it is intelligence, and transitive intelligence, and has time connascent with itself. 
   But the sixth intelligence, if you are willing also to connumerate this, is phantastic knowledge, or the knowledge of the imagination, which by some is denominated intelligence; and the phantasy is called by them passive intellect, because it knows such things as it does know, inwardly, and accompanied with resemblances and figures. 
 

   For it is common to all intelligence to have the objects of its knowledge inward. For in this also intelligence differs from sense. In one order however, intelligence is the thing known itself. In another it ranks as the second, but sees that which is first totally. In another it is partially the thing known, but sees wholes also through that which is partial. In another it sees indeed wholes, but at the same time partially and not at once. And in another, the vision is accompanied with passion. So many therefore, are the differences of intelligence.

   Now, however, phantastic intelligence must not be assumed; since this is not naturally adapted to know truly existing being. For it is indefinite, because it knows the object of its perception accompanied with figure and morphe. But perpetual being is unfigured. And in short, no irrational knowledge is able to survey being itself, since neither is adapted to perceive that which is universal. 
   Nor must the intelligence in the rational soul be assumed. For it does not possess the at-once- collected, and that which is co-ordinate with eternal natures; but it proceeds according to time. 
   No must we assume total intellections; for these are exempt from our knowledge. 
   But Timaeus co-arranges intelligence with reason. The intelligence, therefore, of a partial intellect, must now be assumed. For it is in conjunction with this, that we some time or other perceive real being.
 

   For a sense is in the second duad below the rational soul, so intelligence is in the duad above it. 
   For a partial intellect is proximately established above our essence, elevating and perfecting it, to which we are converted when purified through philosophy, and when we conjoin our own intellectual power with the intelligence of this intellect. 
 

   But what this partial intellect is, and that it is not as one to one rational soul, but is participated through souls which always energize according to it, through which also partial souls sometimes participate of intellectual light, we have elsewhere distinctly and copiously discussed. 
   Now, however, thus much must be assumed, that it is participated indeed by all other proximate daemoniacal souls, but illuminates ours, when we convert ourselves to it, and render the reason which is in us intellectual.
   And as in the Phaedrus Plato calls this the governor of the soul, and says that it alone intellectually perceives real being, but that the soul perceives it together with this intellect, when she is nourished by intellect and science; thus also it must be said that this intelligence is prior to soul, and is truly intelligence [mentioned by Plato] but that it is participated by soul when reason energizes intellectually. 
   Hence Plato says in the following part of this dialogue, that intellect is indeed in the Gods, but that a certain small genus [of men] participates of it. 
   And it seems that in what he says unfolding the knowledge of perpetual being, he first calls it intelligence; but that we may not apprehend it to be that alone, he adds to intelligence reason, distinguishing by a transitive energy the latter from the former. 
   So that when reason intellectually perceives perpetual being, as reason indeed, it energizes transitively, but as perceiving intellectually, with simplicity; understanding each thing as simple at once, yet not all things at once, but passing from some to others. It transitively however perceives intellectually every thing which it perceives as one thing, and as simple.

   After the definition of intelligence however, let us see what reason is, and how it is connascent with intelligence. 
   In the Theaetetus therefore, `logos', reason, is said to have a threefold subsistence; for it is either enunciative, or a discursive procession through the elements [of speech]; or that which exhibits the differences of each thing with respect to others. 
 

   All these significations however, are conversant with compositions and divisions, and are unadapted to the comprehension of eternal being. For the similar is naturally adapted to be apprehended by the similar. But eternal being is simple and indivisible, and is exempt from every thing which is contrary to these. 
   Again, after another manner, one kind of reason is said to be doxastic, another scientific, and another intellectual. For since there are in us opinion, dianoia, and intellect; but I call intellect here, the summit of dianoia; and since the whole of our essence is reason, in each of these reason must be differently surveyed. 
 

  Opinion however, is not naturally adapted to be united to the intelligence of intellect in energy: for on the contrary it is conjoined to irrational knowledge. 
   Nor is dianoia, so far as it proceeds into multitude and division, able to recur to intellect; but on the contrary through the variety of its discursive energies, it is separated from intellectual impartibility. 
   It remains, therefore, that the summit of the soul, and that in it which has most the form of The One, is established in the intelligence of a partial intellect, being through alliance united to it. 
 

   Hence this is the reason which intellectually perceives the intelligibles co-ordinate to our nature, and the energy of which Socrates in the Republic says is intelligence; just as dianoia is the knowledge of things which subsist between intelligibles and the objects of opinion. 
   If, however, intelligence is the energy of this reason, it will be a certain intellect. 
   Plato in the following part of this dialogue says, that this reason in the same manner as science, is ingenerated in the soul, when it is moved about the intelligible. But that science has a more various energy, apprehending some things through others, and intellect a more simple energy, intuitively surveying beings themselves. 
   This highest therefore, and most impartible portion of our nature, Plato now denominates reason, as unfolding to us intellect, and an intelligible nature. 
   For when the soul abandons phantasy and opinion, and various and indefinite knowledge, but recurs to its own impartibility, according to which it is rooted in a partial intellect, and having run back to this, conjoins the energy of itself with the intelligence of that intellect, then it intellectually perceives eternal being together with it, its energy being both one, and twofold, and both sameness and separation being inherent in its intellections. 
   For then the intelligence of the soul becomes more collected, and nearer to eternal things, in order that it may apprehend the intelligible together with intellect, and that the reason which is in us may like a less light, energize in conjunction with one that is greater. For our reason in conjunction with intelligence, sees the intelligible; but the intelligence of intellect always sees it, and always is; and conjoins reason to it, when reason acquires the form of intellect.

   After what manner however, is truly existing being comprehended by a partial intellect, or by reason? 
   For this is still more admirable. May we not say, that though the intelligible itself cannot be comprehended by intellect and reason, because it is superior to all comprehension, and comprehends all things exemptly, yet intellect possessing its own intelligible, is also on this account said to comprehend the whole [of an intelligible nature]. But reason through the intellect which is co-ordinate to itself, receiving the conceptions of real beings, is thus through these said to comprehend being. 
   Perhaps also it signifies, that reason running round the intelligible, and energizing and being moved as about a centre, thus surveys it; intelligence indeed knowing it intransitively and impartibly, but reason dancing as it were round the essence of it in a circle, and evolving the united hypostasis in it of all things.

   In the next place, let us direct our attention to opinion, and consider what it is. 
   That it is therefore the boundary of the whole rational life, and that it is conjoined to the summit of the irrational life, is frequently acknowledged. 
   But we shall now unfold such things as are the peculiarities of the Platonic doctrine; and which are as follow: That the doxastic part comprehends the reasons [or productive principles] of sensibles; that it is this also which knows the essences of them; and that it knows the `oti', or that a thing is, but is ignorant of the cause of it. 
   For since dianoia knows at one and the same time both the essences and the causes of sensibles, but sense knows neither of these; for it is clearly shown in the Theaetetus that sense does not know the essence of a thing, and that it is perfectly ignorant of the cause of the objects of its knowledge; it is necessary that opinion being arranged between sense and dianoia, should know the essences of sensibles, through the reasons which it contains, but should be ignorant of the causes of them. 
   For thus right opinion will differ from science in this, that it alone knows that a thing is, science being able to survey likewise the cause of it. 
   But sense adheres to opinion, being also itself a medium between the instrument of sense and opinion. For the instrument of sense apprehends sensibles accompanied with passion. Hence also it is corrupted through the excess of sensibles. But opinion possesses knowledge undefiled with passion. Sense however participates in a certain respect of passion, but has also something gnostic, so far as it is established in the doxastic part, is illuminated by it, and partakes of the form of reason, since it is in itself irrational. 
   In this, therefore, the series of gnostic powers is terminated, of which indeed intelligence is the leader, which is above reason, and is without transition. But reason has the second order which is the intelligence of our soul, transitively coming into contact with real beings. Opinion has the third order, being a knowledge of sensibles conformable to reason. And sense has the fourth order, being an irrational knowledge of sensibles. 
 

   For dianoia, being a medium between intelligence and opinion, is gnostic of middle forms, which require a more obscure apprehension than that of intelligence, but a clearer perception than that of opinion; as Socrates said on the preceding day, when he defined the different kinds of knowledge by the objects of knowledge.

   It must be said, therefore, that opinion is according to reason, because it possesses gnostic reasons of the essences of things, but that it is otherwise irrational, as being ignorant of causes. For Socrates in the Banquet, speaking of it says, "since it is an irrational thing, how can it be science?" 
   But it must be admitted that sense is entirely irrational. For in short, since each of the senses knows the passion produced about the animal by the object of sense, hence intelligence is an intransitive, but dianoia and reason a transitive knowledge; opinion a knowledge in conjunction with reason but without the assignation of cause; sense an irrational knowledge of passions; and the instrument of sense passion only. 
   Thus, for instance, when an apple is presented to us, the sight indeed knows that it is red from the passion about the eye, the smell that it is fragrant from the passion about the nostrils, the taste that it is sweet, and the touch that it is smooth. What then is it which says that the thing presented to us is an apple? For it is not any one of the partial senses; since each of these knows one certain thing only about the apple, and not the whole of it; nor does even the common sense know this. For this alone distinguishes the differences of the passions; but it does not know that the thing which possesses an essence of such a kind is the whole thing. 
   Hence, it is evident that there is a certain power superior to the senses, which knowing the whole prior to the things which are as it were parts, and surveying the form of it, is impartibly connective of these many powers. This power, therefore, Plato calls opinion, and on this account, he denominates that which is sensible doxastic.

   Farther still, since the senses frequently announce various passions, and not such as things of this kind are in themselves, what is it in us which judges and says, that the sight is deceived when it asserts that the sun is but a foot in diameter, and that the taste which pronounces honey to be bitter, is the taste of those that are diseased? For it is entirely evident that in these, and all such-like particulars, the senses announce indeed their own passions, and are not perfectly deceived. For they say what the passion is about the instruments of sense, and it is a thing of such a kind as they assert it to be; but that which says what the cause is of the passion, and forms a judgement of it, is something different from sense.

   Hence, there is a certain power of the soul superior to sense, which no longer knows sensibles through an instrument but through itself, and corrects the grossness of sensible information. And this power indeed which is reason as with reference to sense, is irrational as with reference to the knowledge of truly existing beings. 
   But sense is simply irrational. On this account, Plato in the Republic calling this power opinion, shows that it is a medium between knowledge and ignorance: for it is indeed a rational knowledge, but it is mingled with irrationality, knowing sensibles in conjunction with sense. 
   But sense is alone irrational, as Timaeus also denominates it; in the first place, because it is also inherent in irrational animals, and is characteristic of every irrational life; for by these things, what is said in the Theaetetus distinguishes it from science. 
   In the second place, because in contradistinction to all the parts of the irrational soul, it is disobedient to reason. For the irascible and epithymetic parts, are obedient to reason and its mandates, and receive from it erudition. But sense though it should hear reason ten thousand times asserting that the sun is greater than the earth, yet would still see it to be a foot in diameter, and would not otherwise announce it to us. 
   In the third place, because neither does it [accurately] know that which it knows. For it is not naturally adapted to see the essence of it. For it does not know what a white thing is, but it knows through passion that it is white. It likewise is not separated from the instrument of sense, and is therefore on this account irrational. For thus in the Gorgias, irrational knowledge is defined to be not scientific, but conjectural. 
   In the fourth place, sense is alone irrational, because it is the boundary of the whole series of knowledge, possesses an essence most remote from reason and intellect, pertains to externals, and effects its apprehension of things through body. For all these particulars demonstrate its irrationality.

   Every thing generated therefore is apprehended by opinion in conjunction with sense; the latter announcing passions, but the former producing from itself the reasons of them, and knowing the essences of sensibles. 
   And as reason when in contact with intelligence sees the intelligible, thus also opinion co-arranged with sense, knows that which is generated. 
   For since the soul is of a middle essence it gives completion to a subsistence between intellect and irrationality. For by its summit it is present with intellect, but by its ultimate part it verges to sense. 
   Hence also Timaeus in the former conjunction, arranges intelligence prior to reason, as being more excellent; but in the second he places opinion before sense. 
   For there indeed, reason is posterior to intelligence, as being a less intellect; but here opinion is prior to sense, as being rational sense. 
   Opinion however, and reason circumscribe the whole breadth of the rational essence. 
   But intellect is our king, and sense our messenger, says the great Plotinus. 
   Reason indeed, together with intellect, sees the intelligible; but by itself it surveys reasons or forms that have a middle subsistence. 
   And opinion in conjunction with sense, sees that which is generated; but by itself it contemplates all the forms it contains, concerning which we have elsewhere spoken, have shown how these forms subsist, how the place of them is the doxastic part of the soul, and that the intelligible is apprehended by reason, but by opinion, the intelligible is seen as a doxastic object. For the object of its knowledge is external to, and not within it, as the intelligible is within reason. Hence the object is not comprehended by it, but is called opinable and not sensible; because opinion knows indeed the essences of things, but sense does not. 
   Hence too, it receives the appellation of a clearer knowledge, which knows what a thing is, but not alone that it is, which latter we say is the employment of sense; and in consequence of this Timaeus very properly calls that which is generated the object of opinion. For this is Pythagoric; since Parmenides also considered the discussion of sensibles, as a discussion according to opinion; sensibles being in their own nature perceptible by this power of the soul. Hence it is not proper to call that which is generated sensible alone, because sense is not gnostic of any essence, nor the object of opinion, without the addition of sense.

   Here however, Aristotle particularly blames the second assertion of Timaeus. For where is it [universally] true that what is perceived by opinion in conjunction with sense is generated and corrupted? For heaven is unbegotten and indestructible, though it is perceived by opinion in conjunction with sense. And Timaeus, in the course of this dialogue, inquires whether the whole heaven was generated. 
   At present, therefore, it must be said by us, that generation and corruption subsist according to analogy in the heavens, not only according to the motions and mutations of figures, but also because a celestial body is not produced by itself, but alone subsists from another cause. Hence it is generated as having the cause of its subsistence suspended from another thing different from itself. Since, however, it not only subsists from, but is connected by another, not being able to connect itself, and is corrupted according to its own proper reason, on this account it assumes generation co-ordinately with corruption. 
   For truly existing and eternal beings generate themselves, and are connected by themselves, whence also they are said to be in their own nature unbegotten and indestructible. If, however, truly existing being is unbegotten , and therefore subsists from itself, that which does not subsist from itself will not be truly unbegotten. And if that which is truly indestructible is naturally adapted to connect itself, that which is not naturally adapted to connect itself will not be truly indestructible. 
   Heaven, however, but I mean by heaven the corporeal-formed nature of it alone, is neither adapted to produce nor to connect itself. For every thing of this kind which produces and connects itself, is impartible. Hence it is neither truly unbegotten nor truly indestructible, but so far as pertains to its corporeal nature, it is generated and made. 
   Farther still, as Aristotle himself says, and clearly and generously demonstrates, no finite body possesses an infinite power. But the celestial body is finite, and therefore does not possess an infinite power. 
   The indestructible, however, so far as indestructible, possesses an infinite power. Hence body, so far as body, is not indestructible. So that from the reasoning of Aristotle it is demonstrated to be a thing of this kind. 
   But after what manner the heaven is unbegotten and perpetual, will be manifest to us shortly after. Now, however, this alone is evident from what has been said, that every thing corporeal, is of itself, or in its own nature generated and corrupted, but never truly is, as Plato also says in the Politicus. For he there observes "that to subsist always invariably the same, alone pertains to the most divine of all things. But the nature of body is not of this order. That, however, which we denominate heaven or the world, possesses indeed many blessed prerogatives from its generator; but, as it partakes of body, it is impossible that it should be entirely free from mutation." We have shown, therefore, how the heaven falls under the above-mentioned distinctions.

   If however, the daemoniacal Aristotle, should again doubt respecting what it said of eternal being, not enduring to say that every thing which always is, is comprehended by intelligence in conjunction with reason; since the most divine of visible objects always exist; we think it fit, that he should not confound the eternal, and that which subsists through the whole of time. For he also distinguishes eternity from time; and attributes the former indeed to intellect, but the latter to heaven, and the motion of heaven. 
   That always-existing being, therefore, the eternal, is a thing of such a kind as Timaeus defines it to be. 
   The most divine, however, of visible objects, are after another manner perpetual, and not according to an eternal permanency. But they are produced in the whole of time from their causes, and the whole of their existence is in becoming to be. This also is said by Aristotle, that eternity is connascent with intelligibles, possessing and comprehending in itself infinite time; and therefore the eternal is truly intelligible. 
   If, however, that which always is, signifies the eternal, why is it necessary to refer the nature of heaven to this perpetual being, and why should we not say that it is always generated, or becoming to be, as being co-extended with the perpetuity of time? So that we shall thus dissolve the objections from his arguments, which he urges against these definitions. Since, however, we have replied to this inquiry, we shall dismiss it; for it will be spoken of hereafter.

   But, in short, the opinion of Plato concerning criteria, may from these things be assumed. For different persons admitting a different criterion, some asserting that it is sense, as the Protagoreans, others opinion, as he who said,

   But when it forms a judgement of middle reasons, it alone uses dianoia and itself, and through this is converted to itself. When also it decides on objects of opinion, it moves opinion; but in judging of objects of imagination, it excites the phantasy, and in judging of sensibles, sense. For when it considers the sensible essence of forms, such as is every sensible object, it uses opinion as the co-adjutor of its speculation. For in this the reasons of sensibles subsist. But when it directs its attention to the position or figure of a certain thing, as for instance, to the manner in which the earth is posited, which has in its summit a habitude to the heavens, it then excites the phantasy, in order that it may survey the object of its inquiry accompanied with interval and morphe, as it is. And when it considers an eclipse, it employs sense as an adjutor in its observations. 
   At one time also, it admits the judgements of the second powers; but at another, it blames the errors which they frequently happen to commit on account of the instruments. 
   Concerning the criteria therefore, thus much may suffice for the present; for we have discussed these things more copiously in our Commentaries on the Theaetetus. From what has been said, however, the great accuracy of the before-mentioned definitions is evident.

   But if you are willing, we will also survey the same thing according to another method. I say, therefore, that the nature which is primarily perpetual being, is that which is eternal according to all things, viz. according to essence, power, and energy. And that the nature which is simply generated, is that which receives all its essence, power and energy in time. For it is necessary that the former should be wholly eternal, but the latter wholly temporal. And that the former should be at once every thing in a self-subsistent manner, but that the latter should have its hypostasis suspended elsewhere than from itself, and consisting in an extension of existence. 
   Since these, however, are the extremes, the media are, things which in a certain respect participate of a portion of being, and in a certain respect communicate with generation. 
   But again, there are two natures which participate of neither of these, one in consequence of being superior, but the other through being inferior to them. 
   For matter is neither being, nor that which is generated. For it is neither comprehended by intelligence, nor is sensible. 
   And this also is true of The One, as Parmenides demonstrates of both these, of the latter in the first, and of the former in the fifth hypothesis. 
   Perpetual being, therefore, is the whole of the intelligible, and the whole of the intellectual genus, every supermundane intellect, every intellect participated by divine souls, and every intellect which is called partial, and is participated by angels, and daemons; and by partial souls, through angels and daemons as media. And as far as to this, perpetual being extends. For every intellect energizes eternally, and is measured in the whole of itself by eternity. 
   But that which is generated, is every thing which is moved in a confused and disorderly manner, and which in conception is surveyed prior to the production of the world; likewise every thing which is properly generated and corrupted, heaven, and all these sensible and visible natures. 
   Timaeus also defines that which is simply generated, and that which is simply perpetual being, to be these. 
   But the intermediate natures are those which communicate with both these; and on each side of them are the natures which participate of neither of these. Hence Timaeus proposes both of them affirmatively and negatively, as for instance, perpetual being, and without generation, and again, that which is generated, and is never real being, in order that through the affirmations he may separate them from things which are the recipients of neither, but that through the negations they may be distinguished from things which in a certain respect participate of both.

   As these, therefore, are the extremes, viz. every intelligible and intellectual essence, and every sensible essence, let us direct our attention to the intermediate nature. 
 

   For Timaeus calls both time and the soul generated. And it is evident that these, as not being sensible, are in a certain respect beings, and in a certain respect generated, but perfectly neither of these. 
   Porphyry, therefore, rightly observes, that Plato now defines the extremes, viz. that which is primarily being, and that which is alone generated, and that he omits the media; such for instance as, that which is at one and the same time being and a generated nature, or that which is both generated and being; of which being and generated are adapted to the nature of souls, but vice versa that which is generated and being, are allied to the summit of generated natures. 
   Such as this, however, is the nature of the universe which vivifies the universe. For this nature so far as it is divisible about bodies, is generated, but so far as it is entirely incorporeal, is unbegotten. 
   But it is absurd to say that matter is both generated and being. For thus it would be superior to generated sensible natures, since these are generated alone, but matter would also participate of being. 
   And if you are willing separately to assume that which is alone perpetual being, and that which is alone generated, by taking away from one of the definitions intellect, and from the other sense; you will produce the definition of the medium. 
 

   For this is known by reason and opinion. For reason knows both itself and opinion, and opinion knows itself and reason; the former indeed both in conjunction with cause; but the latter both, without cause.
   For in this reason and opinion differ from each other. Opinion also is known by reason, and reason by opinion. And the whole [rational] soul subsists through both these which are media. 
   Thus too, by assuming the worse of the two upward terms, viz. reason, and making it to be spurious reason, and of the two downward terms sense, and making it to be insensible sense, you will then have the manner in which Plato thought matter may be known, viz. by spurious reason, and insensible sense. 
   Assuming likewise analogously in each, that which is the better of the two, and making it to be spurious according to that which is more excellent, you will have the manner in which The One is known, viz. by a spurious intellect, and spurious opinion. Hence it is not properly simple, and is not known from cause. It is known therefore by a spurious knowledge, because it is known in a superior manner according to each. 
   For opinion does not know from cause, and The One is not known from cause, but from not having a cause. And intellect knows that which is simple; but a spurious intellect knows The One, because it is superior to intellectual perception. 
   The superior therefore, here, is spurious as with reference to intellect, as The One also is more excellent than that which is simple, such as that is which is intelligible to truly existing intellect, and to which intellect is allied and is not spurious. It perceives therefore, The One, by that in itself which is not intellect. But this is The One in it, according to which also it is a God.

Commentary on the Timaeus of Plato
Proclus
Excepts from volume 15 of the Thomas Taylor Series, p. 195 to 239.
Translated by Thomas Taylor
isbn 1 898910 14 6 and 1 898910 15 4

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