Theory of Colours — trans. Charles Lock Eastlake (1840)

"We can scarcely ever say that the surface of illumined bodies exhibits the real colour of those bodies. Take a white band and place it in the dark, and let it receive light by means of three apertures from the sun, from fire, and from the sky: the white band will be tricoloured."[19]

Aristotle.

"When the light falls on any object and assumes (for example) a red or green tint, it is again reflected on other substances, thus undergoing a new change. But this effect, though it really takes place, is not appreciable by the eye: though the light thus reflected to the eye is composed of a variety of colours, the principal of these only are distinguishable."

Leonardo.

"No colour reflected on the surface of another colour, tinges that surface with its own colour (merely), but will be mixed with various other reflections impinging on the same surface:" but such effects, he observes elsewhere, "are scarcely, if at all, distinguishable in a very diffused light."[20]

Aristotle.

"Thus, all combinations of colours are owing to three causes: the light, the medium through which the light appears, such as water or air, and lastly the local colour from which the light happens to be reflected."

Leonardo.

"All illumined objects partake of the colour of the light they receive.

"Every opaque surface partakes of the colour of the intervening transparent medium, according to the density of such medium and the distance between the eye and the object.

"The medium is of two kinds; either it has a surface, like water, &c., or it is without a common surface, like the air."[21]

In the observations on trees and plants more points of resemblance might be quoted; the passages corresponding with Goethe's views are much more numerous.

It is remarkable that Leonardo, in opposition, it seems to some authorities,[22] agrees with Aristotle in reckoning black and white as colours, placing them at the beginning and end of the scale.[23] Like Aristotle, again, he frequently makes use of the term black, for obscurity; he even goes further, for he seems to consider that blue may be produced by the actual mixture of black and white, provided they are pure.[24] The ancient author, however, explains himself on this point as follows--"We must not attempt to make our observations on these effects by mixing colours as painters mix them, but by remarking the appearances as produced by the rays of light mingling with each other."[25]

When we consider that Leonardo's Treatise professes to embrace the subject of imitation in painting, and that Aristotle's briefly examines the physical nature and appearance of colours, it must be admitted that the latter sustains the above comparison with advantage; and it is somewhat extraordinary that observations indicating so refined a knowledge of nature, as regards the picturesque, should not have been taken into the account, for such appears to be the fact, in the various opinions and conjectures that have been expressed from time to time on the painting of the Greeks. The treatise in question must have been written when Apelles painted, or immediately before; and as a proof that Aristotle's remarks on the effect of semi-transparent mediums were not lost on the artists of his time, the following passage from Pliny is subjoined, for, though it is well known, it acquires additional interest from the foregoing extracts.

"He (Apelles) passed a dark colour over his pictures when finished, so thin that it increased the splendour of the tints, while it protected the surface from dust and dirt: it could only be seen on looking into the picture. The effect of this operation, judiciously managed, was to prevent the colours from being too glaring, and to give the spectator the impression of looking through a transparent crystal. At the same time it seemed almost imperceptibly to add a certain dignity of tone to colours that were too florid." "This," says Reynolds, "is a true and artist-like description of glazing or scumbling, such as was practised by Titian and the rest of the Venetian painters."

The account of Pliny has, in this instance, internal evidence of truth, but it is fully confirmed by the following passage in Aristotle:--"Another mode in which the effect of colours is exhibited is when they appear through each other, as painters employ them when they glaze (ἐπαλειφοντες)[26] a (dark) colour over a lighter one; just as the sun, which is in itself white, assumes a red colour when seen through darkness and smoke. This operation also ensures a variety of colours, for there will be a certain ratio between those which are on the surface and those which are in depth."--_De Sensu et Sensili_.

Aristotle's notion respecting the derivation of colours from white and black may perhaps be illustrated by the following opinion on the very similar theory of Goethe.