Chapter 59

OF THE RELATIVE IMPORTANCE OF TRUTHS:--THIRDLY, THAT TRUTHS OF COLOR ARE THE LEAST IMPORTANT OF ALL TRUTHS.

Sec. 1. Difference between primary and secondary qualities in bodies.

In the two last chapters, we have pointed out general tests of the importance of all truths, which will be sufficient at once to distinguish certain classes of properties in bodies, as more necessary to be told than others, because more characteristic, either of the particular thing to be represented, or of the principles of nature.

According to Locke, Book ii. chap. 8, there are three sorts of qualities in bodies: first, the "bulk, figure, number, situation, and motion or rest of their solid parts: those that are in them, whether we perceive them or not." These he calls primary qualities. Secondly, "the power that is in any body to operate after a peculiar manner on any of our senses," (sensible qualities.) And thirdly, "the power that is in any body to make such a change in another body as that it shall operate on our senses differently from what it did before: these last being usually called _powers_."

Sec. 2. The first are fully characteristic, the second imperfectly so.

Hence he proceeds to prove that those which he calls primary qualities are indeed part of the essence of the body, and characteristic of it; but that the two other kinds of qualities which together he calls secondary, are neither of them more than _powers_ of producing on other objects, or in us, certain effects and sensations. Now a power of influence is always equally characteristic of two objects--the active and passive; for it is as much necessary that there should be a power in the object suffering to receive the impression, as in the object acting to give the impression. (Compare Locke, Book ii. chap. 21, sect. 2.) For supposing two people, as is frequently the case, perceive different scents in the same flower, it is evident that the power in the flower to give this or that depends on the nature of their nerves, as well as on that of its own particles; and that we are as correct in saying it is a power in us to perceive, as in the object to impress. Every power, therefore, being characteristic of the nature of two bodies, is imperfectly and incompletely characteristic of either separately; but the primary qualities, being characteristic only of the body in which they are inherent, are the most important truths connected with it. For the question, what the thing _is_, must precede, and be of more importance than the question, what can it do.

Sec. 3. Color is a secondary quality, therefore less important than form.

Now by Locke's definition above given, only bulk, figure, situation, and motion or rest of solid parts, are primary qualities. Hence all truths of color sink at once into the second rank. He, therefore, who has neglected a truth of form for a truth of color, has neglected a greater truth for a less one.

Sec. 4. Color no distinction between objects of the same species.

And that color is indeed a most unimportant characteristic of objects, will be farther evident on the slightest consideration. The color of plants is constantly changing with the season, and of everything with the quality of light falling on it; but the nature and essence of the thing are independent of these changes. An oak is an oak, whether green with spring or red with winter; a dahlia is a dahlia, whether it be yellow or crimson; and if some monster-hunting botanist should ever frighten the flower blue, still it will be a dahlia; but let one curve of the petals--one groove of the stamens be wanting, and the flower ceases to be the same. Let the roughness of the bark and the angles of the boughs be smoothed or diminished, and the oak ceases to be an oak; but let it retain its inward structure and outward form, and though its leaves grew white, or pink, or blue, or tri-color, it would be a white oak, or a pink oak, or a republican oak, but an oak still. Again, color is hardly ever even a _possible_ distinction between two objects of the same species. Two trees, of the same kind, at the same season, and of the same age, are of absolutely the same color; but they are not of the same form, nor anything like it. There can be no difference in the color of two pieces of rock broken from the same place; but it is impossible they should be of the same form. So that form is not only the chief characteristic of species, but the only characteristic of individuals of a species.

Sec. 5. And different in association from what it is alone.

Again, a color, in association with other colors, is different from the same color seen by itself. It has a distinct and peculiar power upon the retina dependent on its association. Consequently, the color of any object is not more dependent upon the nature of the object itself, and the eye beholding it, than on the color of the objects near it; in this respect also, therefore, it is no characteristic.

Sec. 6. It is not certain whether any two people see the same color in things.

And so great is the uncertainty with respect to those qualities or powers which depend as much on the nature of the object suffering as of the object acting, that it is totally impossible to prove that one man sees in the same thing the same color that another does though he may use the same name for it. One man may see yellow where another sees blue, but as the effect is constant, they agree in the term to be used for it, and both call it blue, or both yellow, having yet totally different ideas attached to the term. And yet neither can be said to see falsely, because the color is not in the thing, but in the thing and them together. But if they see forms differently, one must see falsely, because the form is positive in the object. My friend may see boars blue for anything I know, but it is impossible he should see them with paws instead of hoofs, unless his eyes or brain are diseased. (Compare Locke,