[30] Now these teeth are developed before the flat teeth, in the first place because their function is earlier (for dividing comes before crushing, and the flat teeth are for crushing, the others for dividing), in the second place because the smaller is naturally developed quicker than the larger, even if both start together, and these [789a1] teeth are smaller in size than the grinders, because the bone of the jaw is flat in that part but narrow towards the mouth. From the greater part, therefore, must flow more nutriment to form the teeth, and from the narrower part less.
The act of sucking in itself contributes nothing to the formation of the teeth, but the heat of the milk makes them appear more quickly. A proof of this is that [5] even in suckling animals those young which enjoy hotter milk grow their teeth quicker, heat being conducive to growth.
They are shed, after they have been formed, partly because it is better so (for what is sharp is soon blunted, so that a fresh relay is needed for the work, whereas [10] the flat teeth cannot be blunted but are only smoothed in time by wearing down), partly from necessity because, while the roots of the grinders are fixed where the jaw is flat and the bone strong, those of the front teeth are in a thin part, so that they are weak and easily moved. They grow again because they are shed while the bone is [15] still growing and the animal is still young enough to grow teeth. A proof of this is that even the flat teeth grow for a long time, the last of them cutting the gum at about twenty years of age; indeed in some cases the last teeth have been grown in quite old age. This is because there is much nutriment in the broad part of the [789b1] bones, whereas the front part being thin soon reaches perfection and no residual matter is found in it, the nutriment being consumed in its own growth.
Democritus, however, neglecting the final cause, reduces to necessity all the operations of nature. Now they are necessary, it is true, but yet they are for a final [5] cause and for the sake of what is best in each case. Thus nothing prevents the teeth from being formed and being shed in this way; but it is not on account of these causes but on account of the end; these are causes in the sense of being the moving and efficient instruments and the material. So it is reasonable that nature should perform most of her operations using breath as an instrument, for as some [10] instruments serve many uses in the arts, e.g. the hammer and anvil in the smith’s art, so does breath in things formed by nature. But to say that necessity is the cause is much as if we should think that the water has been drawn off from a dropsical patient on account of the lancet alone, not on account of health, for the sake of [15] which the lancet made the incision.
We have thus spoken of teeth, saying why some are shed and grow again, and others not, and generally for what cause they are formed. And we have spoken of the other affections of the parts which are found to occur not for any final end but of [20] necessity and on account of the motive cause.
**TEXT: H. J. Drossaart Lulofs, OCT, Oxford, 1965
1Reading ⁗ἐτί for ντα.
2History of Animals III 1.
3History of Animals 510a20ff.
4History of Animals III 1.
5Drossaart Lulofs excises ‘like a true skin’.
6Drossaart Lulofs excises ‘Those ovipara . . . develops externally’.
7Reading π ρoϊoῦσα.
8Parts of Animals, IV 9—Drossaart Lulofs excises the reference.
9The text of the obelized passage is uncertain.
10Drossaart Lulofs excises the parenthetical sentence.
11Drossaart Lulofs excises ‘that the semen . . . the body’.
12Drossaart Lulofs excises ‘to a certain . . . otherwise’.
13Frag. 63 Diels-Kranz.
14Frag. 57 Diels-Kranz.
15Frag. 65 Diels-Kranz.
16The obelized passage is textually corrupt.
17Reading ᾗ ἀρχή.
18Drossaart Lulofs marks lines 12 (‘Now that which comes . . .’) to 22 (‘ . . . semen is’) as an interpolation.
19Reading τoύτῳ.
20Reading έκάτεραι for καὶ ↚τεραι.
21Drossaart Lulofs regards the bracketed passage as an interpolation.
22Drossaart Lulofs excises this paragraph.
23Drossaart Lulofs excises the parenthetical sentence.
24See History of Animals VI 18.
25Frag. 79 Diels-Kranz.
26Excised by Drossaart Lulofs.
27See III 11.
1Omitting καὶ σπέρμασι … ἀπoκρίσεσιν.
2‘Aphrodite’ from ἀφρός.
3Drossaart Lulofs marks a lacuna in the text here.
4Omitting τò σπέρμα.
5Drossaart Lulofs regards this paragraph as misplaced.
6See III 3.
7Reading τῆς τε ξηρᾶς καὶ τῆς ꜑ γρῆς.
8See History of Animals III 3.
9Omitting ἀεὶ καί.
1History of Animals 567a30.
2Excised by Wimmer.
3Omitting τήν.
4The phrase between daggers is corrupt.
5See History of Animals VI 3.
6Reading ꜏ σoις μή.
7See Herodotus II 93.
8The text here is uncertain.
9History of Animals 550a17ff.
10Drossaart Lulofs marks a lacuna here.
11Reading ἐπιγίγνεται περίττωμα (Peck).
12Excised by Drossaart Lulofs.
13This paragraph appears to be misplaced.
14Omitting ἐν τoῖς τόπoις ζῴων.
1Omitting τoῦ σπέρματoς.
2Frag. 63 Diels-Kranz.
3Excised by Drossaart Lulofs.
4Reading ↚τερα.
5Excised by Platt.
6Excised by Drossaart Lulofs.
7Frag. 68 Diels-Kranz.
1Sense and Sensibilia 2; On the Soul III 1.
2Drossaart Lulofs excises the sentence in parentheses.
3Omitting καὶ εἰσπνoήν.
4Reading oἷα.
5There appears to be a lacuna in the text here.
6Reading τὴν ἀρχὴν τῷ πνευματικῷ τόπῳ.
7Drossaart Lulofs marks 781a20-b5 as a later addition.
8‘γῆρας’ (‘old age’) connected with ‘γῆ’ (‘earth’).
9Reading καὶ ἐν τῷ γήρᾳ.
10Iliad VIII 83.
ON COLOURS**
T. Loveday and E. S. Forster
1 · Simple colours are those which belong to the elements, i.e. to fire, air, [791a1] water, and earth. Air and water in themselves are by nature white, fire (and the sun) yellow, and earth is naturally white. The variety of hues which earth assumes is due to dying, as is shown by the fact that ashes turn white when the moisture that [5] tinged them is burnt out. It is true they do not turn a pure white, but that is because they are tinged by the smoke, which is black. And this is the reason why lye-mixture turns yellow, the water being coloured by hues of flame and black.
Black is the proper colour of elements in process of transmutation. The [10] remaining colours, it may easily be seen, arise from blending by mixture of these.
Darkness is due to privation of light. For we see black under three different conditions. Either the object of vision1 is naturally black (for black light is always reflected from black objects); or no light at all passes to the eyes from the object (for [15] an invisible object surrounded by a visible patch looks black); and objects always appear black to us when the light reflected from them is rare and scanty. This last condition is the reason why shadows appear black. It also explains the blackness of ruffled water, e.g. of the sea when a ripple passes over it: owing to the roughness of [20] the surface few rays of light fall on the water and the light is dissipated, and so the part which is in shadow appears black. The same principle applies to very dense cloud, and to masses of water and of air which light fails to penetrate; for water and [25] air look black when present in very deep ma
sses, because of the extreme rarity of the rays reflected, the parts of the mass between the illuminated surfaces being in [791b1] darkness and therefore looking black. There are many arguments to prove that darkness is not a colour, but merely privation of light, the best being that darkness, unlike all other objects of vision, is never perceived as having any definite [5] magnitude or any definite shape.
Light is clearly the colour of fire; for it is never found with any other hue than this, and it alone is visible in its own right whilst all other things are rendered visible by it. But there is this point to be considered, that some things, though they are not [10] in their nature fire nor any species of fire, yet seem to produce light. So we cannot say that the colour of fire is identical with light, and yet light is the colour of other things besides fire, but we can say that this colour is to be found in other things [15] besides fire, and yet light is the colour of fire. Anyhow, it is only by aid of light that fire is rendered visible, just as all other objects are made visible by the appearance of their colour.2
The colour black occurs when air and water are thoroughly burnt by fire, and [20] this is the reason why burning objects turn black, as e.g. wood and charcoal when the fire is put out, and smoke from clay as the moisture in the clay is all secreted and burnt. This is also why the blackest smoke is given off by fat and greasy substances like oil and pitch and resinous wood, because these objects burn most completely, and the process of combustion is most continuous in them.
[25] Again, things turn black through which water percolates if they first become coated with lichen and then the moisture dries off. The stucco on walls is an [792a1] example of this, and much the same applies to stones under water, which get covered with lichen and turn black when dried.
This then is the list of simple colours.
[5] 2 · From these the rest are derived in all their variety of chromatic effects by blending of them and by their presence in varying strengths. The different shades of crimson and violet depend on differences in the strength of their constituents, whilst blending is exemplified by mixture of white with black, which gives grey. So a dusky [10] black mixed with light gives crimson. For observation teaches us that black mixed with sunlight or firelight always turns crimson, and that black objects heated in the fire all change to a crimson colour, as e.g. smoky tongues of flame, or charcoal when [15] subjected to intense heat, are seen to have a crimson colour. But a vivid bright violet is obtained from a blend of feeble sunlight with a thin dusky white. That is why the air sometimes looks purple at sunrise and sunset, for then the air is especially dusky [20] and the impinging rays feeble. So, too, the sea takes a purple hue when the waves rise so that one side of them is in shadow: the rays of the sun strike without force on the slope and so produce a violet colour. The same thing may also be observed in [25] birds’ wings, which get a purple colour if extended in a certain way against the light, but if the amount of light falling on them is diminished the result is the dark colour called brown, whilst a great quantity of light blended with primary black gives crimson. Add vividness and lustre, and crimson changes to flame-colour.
For it is after this fashion that we ought to proceed in treating of the blending [30] of colours, starting from an observed colour as our basis and making mixtures with it. (But we must not assign to all colours a similar origin, for there are some colours which, though not simple, bear the same relation to their products that simple colours bear to them, inasmuch as a simple colour has to be mixed with one other [792b1] colour to produce them.) And when the constituents are obscure in the compound product, we must still try to establish our conclusions by reference to observation.3 For, whether we are considering the blend which gives violet or crimson, or whether we are considering the mixtures of these colours which produce other tints, we must explain their origin on the same kind of principles, even though they look [5] dissimilar.4 So we must start from a colour previously established, and observe what happens when it is blent. Thus we find that wine colour results from blending airy rays with pure lustrous black, as may be seen in grapes on the bunch, which grow wine-coloured as they ripen; for, as they blacken, their crimson turns to a violet. [10] After the manner indicated we must treat all differences of colours, getting comparisons by moving coloured objects,5 keeping our eye on actual phenomena, assimilating different cases of mixture on the strength of the particular known instances in which a given origin and blending produce a certain chromatic effect, [15] and verifying our results. But we must not proceed in this inquiry by blending pigments as painters do, but rather by comparing the rays reflected from the aforesaid known colours, this being the best way of investigating the true nature of [20] colour-blends. Verification from experience and observation of similarities are necessary if we are to arrive at clear conclusions about the origin of different colours, and the chief ground of similarities is the common origin of nearly all colours in blends of different strengths of sunlight and firelight, and of air and water. At the same time we ought to draw comparisons from the blends of other [25] colours with rays of light. Thus charcoal and smoke, and rust, and brimstone, and birds’ plumage blent, some with firelight and others with sunlight, produce a great variety of chromatic effects. And we must also observe the results of maturation in [30] plants and fruit, and in hair, feathers, and so on.
3 · We must not omit to consider the several conditions which give rise to the manifold tints and infinite variety of colours. It will be found that variations of tint occur either because colours are possessed by varying and irregular strengths of light and shade (for both light and shade may be present in very different strengths, [793a1] and so whether pure or already mixed with colours they alter the tints of the colours); or because the colours blent vary in fullness and in powers; or because they [5] are blent in different proportions. Thus violet and crimson and white and all colours vary very much both in strength and in intermixture and purity.
Difference of hue may also depend on the brightness and lustre or dimness and [10] dullness of the blend. Lustre is simply continuity and density of light; e.g. we have a glistening gold colour when the yellow colour of sunlight is highly concentrated and therefore lustrous. That explains why pigeons’ necks and drops of falling water look [15] lustrous when light is reflected from them.
Again, some objects change their colour and assume a variety of hues when polished by rubbing or other means, like silver, gold, copper, and iron, when they are polished; and some kinds of stones give rise to different colours, like . . .6 which are [20] black but make white marks. This is because the original composition of all such substances is of small dense and black particles, but in the course of their formation they have been tinged, and all the pores through which the tincture passed have taken its colour, so that finally the whole material appears to be of that colour. But [25] the dust that is rubbed off from them loses this golden or copper colour (or whatever the hue may be), and is quite black, because rubbing breaks up the pores through [30] which the tincture passed, and black is the original colour of the substance.7 The other colour is no longer apparent because the dye is dissipated, and so we see the original natural colour of the material, and this is why these substances all appear black. But when rubbed against a smooth and even surface, as e.g. against a [793b1] touchstone, they lose their blackness and get back their other colour, which comes through where the lines of the tincture in the pores are unbroken and continuous.
In the case of objects burning, dissolving, or melting in the fire, we find that [5] those have the greatest variety which are dark in colour and give off a thin hazy smoke, such as the smoke of brimstone or rusty copper vessels, and those which, like silver, are dense and smooth.
Apart from these cases, variety of hue is characteristic of all dark smooth [10] objects, such as water, clouds, and birds’ plumage. For these last, owing to their smoothness and the variety of blends into which the impinging rays of light enter, show various colours, as also does darkness.
We nev
er see a colour in absolute purity: it is always blent, if not with another [15] colour, then with rays of light or with shadows, and so it assumes a tint other than its own. That is why objects assume different tints when seen in shade and in light and sunshine, and according as the rays of light are strong or weak, and the objects themselves slope this way or that, and under other differential conditions. Again, [20] they vary when seen by firelight or moonlight or torchlight, because the colours of those lights differ somewhat. They vary also in consequence of mixture with other colours, for they are coloured by passing through one another. For if light falls on a given object and is coloured by it crimson or herb-green, and then the light reflected [25] from that object falls on another colour, it is again modified by this second colour, and so it gets a new chromatic blend. This happening to it continuously, though imperceptibly, light when it reaches the eye may be a blend of many colours, though the sensation produced is not of a blend but of some colour predominant in the [30] blend. This is why objects under water tend to have the colour of water, and why reflections in mirrors resemble the colour of the mirrors, and we must suppose that the same thing happens in the case of air. Thus all hues represent a threefold [794a1] mixture of light, a translucent medium (e.g. water or air), and underlying colours from which the light is reflected. A translucent white medium, when of a very rare [5] consistency, looks hazy in colour; but if it is dense, like water or glass, or air when thick, a sort of mist covers its surface, because the rays of light are inadequate at every point on it owing to its density, and so we cannot see the interior clearly. Air seen close at hand appears to have no colour, for it is so rare that it yields and gives [10] passage to the denser rays of light, which thus shine through it; but when seen in a deep mass it looks practically dark blue. This again is the result of its rarity, for where light fails the air lets darkness through and looks dark blue. When densified, [15] air is, like water, the whitest of things.
The Complete Works of Aristotle Page 213