The Basic Works of Aristotle (Modern Library Classics)
Page 71
Now we have discussed ‘indivisible planes’ in the preceding treatise.80 (35) But with regard to the assumption of ‘indivisible solids’, although we must not now enter upon a detailed study of its consequences, the following criticisms fall within the compass of a short digression:—
(I) The Atomists are committed to the view that every ‘indivisible’ is incapable alike of receiving a sensible property (for nothing can ‘suffer action’ except through the void) and of producing one—no ‘indivisible’ can be, e. g., either hard or cold. [326a] Yet it is surely a paradox that an exception is made of ‘the hot’—‘the hot’ being assigned as peculiar to the spherical figure: for, (5) that being so, its ‘contrary’ also (‘the cold’) is bound to belong to another of the figures. If, however, these properties (heat and cold) do belong to the ‘indivisibles’, it is a further paradox that they should not possess heaviness and lightness, (10) and hardness and softness. And yet Democritus says ‘the more any indivisible exceeds, the heavier it is’—to which we must clearly add ‘and the hotter it is’. But if that is their character, it is impossible they should not be affected by one another: the ‘slightly-hot indivisible’, e. g., will inevitably suffer action from one which far exceeds it in heat. Again, if any ‘indivisible’ is ‘hard’, there must also be one which is ‘soft’: but ‘the soft’ derives its very name from the fact that it suffers a certain action—for ‘soft’ is that which yields to pressure. (II) But further, not only is it paradoxical (i) that no property except figure should belong to the ‘indivisibles’: it is also paradoxical (ii) that, (15) if other properties do belong to them, one only of these additional properties should attach to each—e. g. that this ‘indivisible’ should be cold and that ‘indivisible’ hot. For, on that supposition, their substance would not even be uniform.81 And it is equally impossible (iii) that more than one of these additional properties should belong to the single ‘indivisible’. For, being indivisible, it will possess these properties in the same point82—so that, if it ‘suffers action’ by being chilled, it will also, qua chilled, ‘act’ or ‘suffer action’ in some other way. (20) And the same line of argument applies to all the other properties too: for the difficulty we have just raised confronts, as a necessary consequence, all who advocate ‘indivisibles’ (whether solids or planes), since their ‘indivisibles’ cannot become either ‘rarer’ or ‘denser’ inasmuch as there is no void in them. (III) It is a further paradox that there should be small ‘indivisibles’, but not large ones. (25) For it is natural enough, from the ordinary point of view, that the larger bodies should be more liable to fracture than the small ones, since they (viz. the large bodies) are easily broken up because they collide with many other bodies. But why should indivisibility as such be the property of small, rather than of large, bodies? (IV) Again, is the substance of all those solids uniform, or do they fall into sets which differ from one another—as if, (30) e. g., some of them, in their aggregated bulk, were ‘fiery’, others ‘earthy’? For (i) if all of them are uniform in substance, what is it that separated one from another? Or why, when they come into contact, do they not coalesce into one, as drops of water run together when drop touches drop (for the two cases are precisely parallel)? On the other hand (ii) if they fall into differing sets, how are these characterized? It is clear, too, (35) that these,83 rather than the ‘figures’, ought to be postulated as ‘original reals’, i. e. causes from which the phenomena result. [326b] Moreover, if they differed in substance, they would both act and suffer action on coming into reciprocal contact. (V) Again, what is it which sets them moving? For if their ‘mover’ is other than themselves, they are such as to ‘suffer action’. If, on the other hand, each of them sets itself in motion, either (a) it will be divisible (‘imparting motion’ qua this, ‘being moved’ qua that), (5) or (b) contrary properties will attach to it in the same respect—i. e. ‘matter’ will be identical-in-potentiality as well as numerically-identical.84
As to the thinkers who explain modification of property through the movement facilitated by the pores, if this is supposed to occur notwithstanding the fact that the pores are filled, their postulate of pores is superfluous. For if the whole body suffers action under these conditions, it would suffer action in the same way even if it had no pores but were just its own continuous self. (10) Moreover, how can their account of ‘vision through a medium’ be correct? It is impossible for
As a general criticism we must urge that to postulate pores is superfluous. For if the agent produces no effect by touching the patient, neither will it produce any by passing through its pores. On the other hand, if it acts by contact, then—even without pores—some things will ‘suffer action’ and others will ‘act’, provided they are by nature adapted for reciprocal action and passion. (25) Our arguments have shown that it is either false or futile to advocate pores in the sense in which some thinkers conceive them. But since bodies are divisible through and through, the postulate of pores is ridiculous: for, qua divisible, a body can fall into separate parts.
9 Let us explain the way in which things in fact possess the power of generating, (30) and of acting and suffering action: and let us start from the principle we have often enunciated. For, assuming the distinction between (a) that which is potentially and (b) that which is actually such-and-such, it is the nature of the first, precisely in so far as it is what it is, to suffer action through and through, not merely to be susceptible in some parts while insusceptible in others. But its susceptibility varies in degree, according as it is more or less such-and-such, and one would be more justified in speaking of ‘pores’ in this connexion88: for instance, (35) in the metals there are veins of ‘the susceptible’ stretching continuously through the substance. [327a]
So long, indeed, as any body is naturally coherent and one, it is insusceptible. So, too, bodies are insusceptible so long as they are not in contact either with one another or with other bodies which are by nature such as to act and suffer action. (To illustrate my meaning: Fire heats not only when in contact, but also from a distance. For the fire heats the air, and the air—being by nature such as both to act and suffer action—heats the body. (5)) But the supposition that a body is ‘susceptible in some parts, but insusceptible in others’
� and ‘composition’, nor yet by ‘turning’ and ‘intercontact’ as Democritus asserts; for it has passed from the liquid to the solid state without any change of ‘grouping’ or ‘position’ in the constituents of its substance. (20) Nor are there contained within it those ‘hard’ (i. e. congealed) particles ‘indivisible in their bulk’: on the contrary, it is liquid—and again, solid and congealed—uniformly all through. This theory, it must be added, makes growth and diminution impossible also. For if there is to be apposition (instead of the growing thing having changed as a whole, either by the admixture of something or by its own transformation), (25) increase of size will not have resulted in any and every part.
So much, then, to establish that things generate and are generated, act and suffer action, reciprocally; and to distinguish the way in which these processes can occur from the (impossible) way in which some thinkers say they occur.
10 But we have still to explain ‘combination’, for that was the third of the subjects we originally91 proposed to discuss. (30) Our explanation will proceed on the same method as before. We must inquire: What is ‘combination’, and what is that which can ‘combine’? Of what things, and under what conditions, is ‘combination’ a property? And, further, does ‘combination’ exist in fact, or is it false to assert its existence?
For, (35) according to some thinkers, it is impossible for one thing to be combined with another. They argue that (i) if both the ‘combined’ constituents persist unaltered, they are no more ‘combined’ now than they were before, but are in the same condition: while (ii) if one has been destroyed, the constituents have not been ‘combined’—on the contrary, one constituent is and the other is not, whereas ‘combination’ demands uniformity of condition in them both: and on the same principle (iii) even if both the combining constituents have been destroyed as the result of their coalescence, (5) they cannot ‘have been combined’ since they have no being at all. [327b]
What we have in this argument is, it would seem, a demand for the precise distinction of ‘combination’ from coming-to-be and passing-away (for it is obvious that ‘combination’, if it exists, must differ from these processes) and for the precise distinction of the ‘combinable’ from that which is such as to come-to-be and pass-away. (10) As soon, therefore, as these distinctions are clear, the difficulties raised by the argument would be solved.
Now (i) we do not speak of the wood as ‘combined’ with the fire, nor of its burning as a ‘combining’ either of its particles with one another or of itself with the fire: what we say is that ‘the fire is coming-to-be, but the wood is passing-away’. Similarly, (15) we speak neither (ii) of the food as ‘combining’ with the body, nor (iii) of the shape as ‘combining’ with the wax and thus fashioning the lump. Nor can body ‘combine’ with white, nor (to generalize) ‘properties’ and ‘states’ with ‘things’: for we see them persisting unaltered.92 But again (iv) white and knowledge cannot be ‘combined’ either, (20) nor any other of the ‘adjectivals’. (Indeed, this is a blemish in the theory of those who assert that ‘once upon a time all things were together and combined’. For not everything can ‘combine’ with everything. On the contrary, both of the constituents that are combined in the compound must originally have existed in separation: but no property can have separate existence.)
Since, however, some things are-potentially while others are-actually, the constituents combined in a compound can ‘be’ in a sense and yet ‘not-be’. The compound may be-actually other than the constituents from which it has resulted; nevertheless each of them may still be-potentially what it was before they were combined, (25) and both of them may survive undestroyed. (For this was the difficulty that emerged in the previous argument: and it is evident that the combining constituents not only coalesce, having formerly existed in separation, but also can again be separated out from the compound.) The constituents, therefore, neither (a) persist actually, (30) as ‘body’ and ‘white’ persist: nor (b) are they destroyed (either one of them or both), for their ‘power of action’ is preserved. Hence these difficulties may be dismissed: but the problem immediately connected with them—‘whether combination is something relative to perception’—must be set out and discussed.
When the combining constituents have been divided into parts so small, and have been juxtaposed in such a manner that perception fails to discriminate them one from another, have they then ‘been combined’? Or ought we to say ‘No, (35) not until any and every part of one constituent is juxtaposed to a part of the other’? The term, no doubt, is applied in the former sense: we speak, e. g., of wheat having been ‘combined’ with barley when each grain of the one is juxtaposed to a grain of the other. [328a] But every body is divisible and therefore, since body ‘combined’ with body is uniform in texture throughout, any and every part of each constituent ought to be juxtaposed to a part of the other. (5)
No body, however, can be divided into its ‘least’ parts: and ‘composition’ is not identical with ‘combination’, but other than it. From these premises it clearly follows (i) that so long as the constituents are preserved in small particles, we must not speak of them as ‘combined’. (For this will be a ‘composition’ instead of a ‘blending’ or ‘combination’: nor will every portion of the resultant exhibit the same ratio between its constituents as the whole. But we maintain that, (10) if ‘combination’ has taken place, the compound must be uniform in texture throughout—any part of such a compound being the same as the whole, just as any part of water is water: whereas, if ‘combination’ is ‘composition of the small particles’, nothing of the kind will happen. On the contrary, the constituents will only be ‘combined’ relatively to perception: and the same thing will be ‘combined’ to one percipient, if his sight is not sharp,
Now, as we maintain,93 some things are such as to act and others such as to suffer action from them. Moreover, some things—viz. (20) those which have the same matter—‘reciprocate’, i. e. are such as to act upon one another and to suffer action from one another; while other things, viz. agents which have not the same matter as their patients, act without themselves suffering action. Such agents cannot ‘combine’—that is why neither the art of healing nor health produces health by ‘combining’ with the bodies of the patients. Amongst those things, however, which are reciprocally active and passive, some are easily-divisible. Now (i) if a great quantity (or a large bulk) of one of these easily-divisible ‘reciprocating’ materials be brought together with a little (or with a small piece) of another, (25) the effect produced is not ‘combination’, but increase of the dominant: for the other material is transformed into the dominant. (That is why a drop of wine does not ‘combine’ with ten thousand gallons of water: for its form is dissolved, and it94 is changed so as to merge in the total volume of water.) On the other hand (ii) when there is a certain equilibrium between their ‘powers of action’, (30) then each of them changes out of its own nature towards the dominant: yet neither becomes the other, but both become an intermediate with properties common to both.95
Thus it is clear that only those agents are ‘combinable’ which involve a contrariety—for these are such as to suffer action reciprocally. And, further, they combine more freely if small pieces of each of them are juxtaposed. For in that condition they change one another more easily and more quickly; whereas this effect takes a long time when agent and patient are present in bulk. [328b] (35)
Hence, amongst the divisible susceptible materials, those whose shape is readily adaptable have a tendency to combine: for they are easily divided into small particles, since that is precisely what ‘being readi
ly adaptable in shape’ implies. For instance, liquids are the most ‘combinable’ of all bodies—because, of all divisible materials, the liquid is most readily adaptable in shape, unless it be viscous. Viscous liquids, (5) it is true, produce no effect except to increase the volume and bulk. But when one of the constituents is alone susceptible—or superlatively susceptible, the other being susceptible in a very slight degree—the compound resulting from their combination is either no greater in volume or only a little greater. This is what happens when tin is combined with bronze. For some things display a hesitating and ambiguous attitude towards one another—showing a slight tendency to combine and also an inclination to behave as ‘receptive matter’ and ‘form’ respectively. (10) The behaviour of these metals is a case in point. For the tin almost vanishes, behaving as if it were an immaterial property of the bronze: having been combined, it disappears, leaving no trace except the colour it has imparted to the bronze. The same phenomenon occurs in other instances too.
It is clear, then, from the foregoing account, that ‘combination’ occurs, (15) what it is, to what it is due, and what kind of thing is ‘combinable’. The phenomenon depends upon the fact that some things are such as to be (a) reciprocally susceptible and (b) readily adaptable in shape, i. e. easily divisible. For such things can be ‘combined’ without its being necessary either that they should have been destroyed or that they should survive absolutely unaltered: and their ‘combination’ need not be a ‘composition’, nor merely ‘relative to perception’. On the contrary: anything is ‘combinable’ which, (20) being readily adaptable in shape, is such as to suffer action and to act; and it is ‘combinable with’ another thing similarly characterized (for the ‘combinable’ is relative to the ‘combinable’); and ‘combination’ is unification of the ‘combinables’, resulting from their ‘alteration’.