which the word Arsenic is derived, | posited in this manner by agitating was an ancient epithet applied to the flour of wheat in water; and those natural substances which pos- lastly, it has been applied to a peculiar sessed strong and acrimonious pro- vegetable principle, which, like starch, perties, and as the poisonous quality is insoluble in cold, but completely of arsenic was found to be remark- soluble in boiling water, with which ably powerful, the term was especi- it forms a gelatinous solution. This ally applied to Orpiment, the form in indefinite meaning of the word fecula, which this metal most usually occurred. has created numerous mistakes in So the term Verbena (quasi Herb na) pharmaceutic chemistry. Elaterium, originally denoted all those herbs for instance, is said to be fecula, and, that were held sacred on account of in the original sense of the word, it their being employed in the rites of is properly so called, inasmuch as it sacrifice, as we learn from the poets; is procured from a vegetable juice by but as one herb was usually adopted spontaneous subsidence, but in the upon these occasions, the word Ver- limited and modern acceptation of the bena came to denote that particular term it conveys an erroneous idea; herb only, and it is transmitted to us for instead of the active principle of to this day under the same title, viz. the juice residing in fecula, it is a Verbena or Vervain, and indeed until peculiar proximate principle, sui genlately it enjoyed the medical reputa- eris, to which I have ventured to tion which its sacred origin conferred bestow the name of Elatin. For the upon it, for it was worn suspended same reason, much doubt and obaround the neck as an amulet. Vitriol, scurity involve the meaning of the in the original application of the word, word Extract, because it is applied denoted any crystalline body with a generally to any substance obtained certain degree of transparency (vit- by the evaporation of a vegetable rum); it is hardly necessary to ob- solution, and specifically to a peculiar serve that the term is now appropri- proximate principle, possessed of cerated to a particular species: in the tain characters, by which it is dissame manner, Bark, which is a general tinguished from every other elementerm, is applied to express one genus, tary body." and by way of eminence it has the article The prefixed, as The bark: the same observation will apply to the word Opium, which, in its primitive sense, signifies any juice (orròs, Succus), while it now only denotes one species, viz. that of the poppy. So, again, Elaterium was used by Hippocrates to signify various internal applications, especially purgatives, of a violent and drastic nature (from the word λaúvw, agito, moveo, stimulo), but by succeeding authors it was exclusively applied to denote the active matter which subsides from the juice of the wild cucumber. The word Fecula, again, originally meant to imply any substance which was derived by spontaneous subsidence from a liquid (from fax, the grounds or settlement of any liquor); afterwards it was applied to Starch, which is de

A generic term is always liable to become thus limited to a single species, or even individual, if people have occasion to think and speak of that individual or species much oftener than of anything else which is contained in the genus. Thus by cattle, a stagecoachman will understand horses; beasts, in the language of agriculturists, stands for oxen; and birds, with some sportsmen, for partridges only. The law of language which operates in these trivial instances is the very same in conformity to which the terms Ocós, Deus, and God were adopted from Polytheism by Christianity, to express the single object of its own adoration. Almost all the terminology of the Christian Church is made up of words originally used in a much more general acceptation: Ecclesia, Assembly; Bishop, Episco

pus, Overseer; Priest, Presbyter, | fluence of a connotation thus acquired Elder; Deacon, Diaconus, Adminis- on the prevailing habits of thought, trator; Sacrament, a vow of allegiance; Evangelium, good tidings; and some words, as Minister, are still used both in the general and in the limited sense. It would be interesting to trace the progress by which Author came, in its most familiar sense, to signify a writer, and Toiηrns, or maker, a poet.

Of the incorporation into the meaning of a term of circumstances accidentally connected with it at some particular period, as in the case of Pagan, instances might easily be multiplied. Physician (quoikos, or naturalist) became, in England, synonymous with a healer of diseases, because until a comparatively late period medical practitioners were the only naturalists. Clerc, or clericus, a scholar, came to signify an ecclesiastic, because the clergy were for many centuries the only scholars.

especially in morals and politics, has been well pointed out on many occasions by Bentham. It gives rise to the fallacy of "question-begging names." The very property which we are inquiring whether a thing possesses or not, has become so associated with the name of the thing as to be part of its meaning, insomuch that by merely uttering the name we assume the point which was to be made out one of the most frequent sources of apparently self-evident propositions.

Without any further multiplication of examples to illustrate the changes which usage is continually making in the signification of terms, I shall add, as a practical rule, that the logician, not being able to prevent such transformations, should submit to them with a good grace when they are irrevocably effected, and if a definition is necessary, define the word according to its new meaning, retaining the former as a second signification, if it is needed, and if there is any chance of being able to preserve it either in the language of philosophy or in common use. Logicians cannot make the meaning of any but scientific terms: that of all other words is made by the collective human race. But logicians can ascertain clearly what it is which, working obscurely, has guided the general mind to a particular employment of a name; and when they have found this, they can clothe it in such distinct and permanent terms, that mankind shall see the meaning which before they only felt, and shall not suffer it to be afterwards forgotten or misapprehended.

Of all ideas, however, the most liable to cling by association to any thing with which they have ever been connected by proximity are those of our pleasures and pains, or of the things which we habitually contemplate as sources of our pleasures or pains. The additional connotation, therefore, which a word soonest and most readily takes on is that of agreeableness or painfulness, in their various kinds and degrees of being a good or bad thing; desirable or to be avoided; an object of hatred, of dread, contempt, admiration, hope, or love. Accordingly there is hardly a single name, expressive of any moral or social fact calculated to call forth strong affections either of a favourable or of a hostile nature, which does not carry with it decidedly and irresistibly a connotation of those strong affections, or, at the least, of approbation or censure; insomuch that to employ those names in conjunction with others by which the contrary sentiments THE PRINCIPLES OF A PHILOSOPHICAL

were expressed, would produce the effect of a paradox, or even a contradiction in terms. The baneful in

CHAPTER VI.

LANGUAGE FURTHER CONSIDERED.

§ I. WE have thus far considered only one of the requisites of a lan

guage adapted for the investigation | cellent remarks which he has made of truth-that its terms shall each on this important branch of our subof them convey a determinate and ject. unmistakable meaning. There are, however, as we have already remarked, other requisites: some of them important only in the second degree, but one which is fundamental, and barely yields in point of import ance, if it yields at all to the quality which we have already discussed at so much length. That the language may be fitted for its purposes, not only should every word perfectly express its meaning, but there should be no important meaning without its word. Whatever we have occasion to think of often, and for scientific purposes, ought to have a name appropriated to it.

This requisite of philosophical language may be considered under three different heads, that number of separate conditions being involved in it.

"The meaning of [descriptive] technical terms can be fixed in the first instance only by convention, and can be made intelligible only by presenting to the senses that which the terins are to signify. The knowledge of a colour by its name can only be taught through the eye. No description can convey to a hearer what we mean by apple-green or French-grey. It might, perhaps, be supposed that, in the first example, the term apple, referring to so familiar an object, sufficiently suggests the colour intended. But it may easily be seen that this is not true; for apples are of many different hues of green, and it is only by a conventional selection that we can appropriate the term to one special shade. When this appropriation is once made, the term refers to the sensation, and not to the parts of the term; for these enter into the compound merely as a help to the memory, whether the suggestion be a natural connection as in apple-green,' or a casual one as in

§ 2. First, there ought to be all such names as are needful for making such a record of individual observations that the words of the record shall exactly show what fact it isFrench-grey.' which has been observed. In other words, there should be an accurate Descriptive Terminology.

The only things which we can observe directly being our own sensations or other feelings, a complete descriptive language would be one in which there should be a name for every variety of elementary sensation or feeling. Combinations of sensations or feelings may always be described if we have a name for each of the elementary feelings which compose them; but brevity of description and clearness (which often depends very much on brevity) are greatly promoted by giving distinctive names not to the elements alone, but also to all combinations which are of frequent recurrence. On this occasion I cannot do better than quote from Dr. Whewell* some of the ex

* History of Scientific Ideas, ii. 110, 111.

In order to derive due advantage from technical terms of the kind, they must be associated immediately with the perception to which they belong, and not connected with it through the vague usages of common language. The memory must retain the sensation; and the technical word must be understood as directly as the most familiar word, and more distinctly. When we find such terms as tin-white or pinchbeckbrown, the metallic colour so denoted ought to start up in our memory without delay or search.

"This, which it is most important to recollect with respect to the simpler properties of bodies, as colour and form, is no less true with respect to more compound notions. In all cases the term is fixed to a peculiar meaning by convention; and the student, in order to use the word, must be completely familiar with the convention, so that he has no need to frame

conjectures from the word itself. Such to surpass the perfection to which this conjectures would always be insecure, quality of a philosophical language has and often erroneous. Thus the term been carried. papilionaceous applied to a flower is "The formation* of an exact and employed to indicate, not only a re- extensive descriptive language for bosemblance to a butterfly, but a resem-tany has been executed with a degree blance arising from five petals of a of skill and felicity, which, before it certain peculiar shape and arrange- was attained, could hardly have been ment; and even if the resemblance were much stronger than it is in such cases, yet, if it were produced in a different way, as, for example, by one petal or two only, instead of a standard' two wings,' and a 'keel' consisting of two parts more or less united into one, we should be no longer justified in speaking of it as a 'papilionaceous' flower.'

6

When, however, the thing named is, as in this last case, a combination of simple sensations, it is not necessary, in order to learn the meaning of the word, that the student should refer back to the sensations themselves; it may be communicated to him through the medium of other words; the terms, in short, may be defined. But the names of elementary sensations, or elementary feelings of any sort, cannot be defined; nor is there any mode of making their signification known but by making the learner experience the sensation, or referring him, through some known mark, to his remembrance of having experienced it before. Hence it is only the impressions on the outward senses, or those inward feelings which are connected in a very obvious and uniform manner with outward objects, that are really susceptible of an exact descriptive language. The countless variety of sensations which arise, for instance, from disease, or from peculiar physiological states, it would be in vain to attempt to name; for as no one can judge whether the sensation I have is the same with his, the name cannot have, to us two, real community of meaning. The same may be said to a considerable extent of purely mental feelings. But in some of the sciences which are conversant with external objects, it is scarcely possible

dreamt of as attainable. Every part of a plant has been named; and the form of every part, even the most minute, has had a large assemblage of descriptive terms appropriated to it, by means of which the botanist can convey and receive knowledge of form and structure, as exactly as if each minute part were presented to him vastly magnified. This acquisition was part of the Linnæan reform.

Tournefort,' says Decandolle, 'appears to have been the first who really perceived the utility of fixing the sense of terms in such a way as always to employ the same word in the same sense, and always to express the same idea by the same words; but it was Linnæus who really created and fixed this botanical language, and this is his fairest claim to glory, for by this fixation of language he has shed clearness and precision over all parts of the science.'

"It is not necessary here to give any detailed account of the terms of botany. The fundamental ones have been gradually introduced, as the part of plants were more carefully and minutely examined. Thus the flower was necessarily distinguished into the calyx, the corolla, the stamens, and the pistils; the sections of the corolla were termed petals by Columna; those of the calyx were called sepals by Necker. Sometimes terms of greater generality were devised; as perianth, to include the calyx and corolla, whether one or both of these were present: pericarp, for the part enclosing the grain, of whatever kind it be, fruit, nut, pod, &c. And, it may easily be imagined that descriptive terms may, by definition and combination, become very

but by its properties generally. I The words Nomenclature and Termean, the Kinds of things, in the minology are employed by most sense which, in this treatise, has been authors almost indiscriminately; Dr. specially attached to that term. By Whewell being, as far as I am aware, a Kind, it will be remembered, we the first writer who has regularly mean one of those classes which are assigned to the two words different distinguished from all others not by meanings. The distinction, however, one or a few definite properties, but which he has drawn between them by an unknown multitude of them; being real and important, his example the combination of properties on which is likely to be followed; and (as is the class is grounded being a mere apt to be the case when such innova index to an indefinite number of other tions in language are felicitously made) distinctive attributes. The class horse a vague sense of the distinction is found is a Kind, because the things which to have influenced the employment of agree in possessing the characters by the terms in common practice, before which we recognise a horse, agree in the expediency had been pointed out a great number of other properties, of discriminating them philosophically. as we know, and, it cannot be doubted, Every one would say that the reform in many more than we know. Animal, effected by Lavoisier and Guytonagain, is a Kind, because no definition Morveau in the language of chemistry that could be given of the name animal consisted in the introduction of a new could either exhaust the properties nomenclature, not of a new terminocommon to all animals, or supply pre-logy. Linear, lanceolate, oval, or obmises from which the remainder of long, serrated, dentate, or crenate those properties could be inferred. leaves, are expressions forming part But a combination of properties which of the terminology of botany while the does not give evidence of the existence names "Viola odorata" and "Ulex of any other independent peculiarities, Europæus "belong to its nomenclature. does not constitute a Kind. White horse, therefore, is not a Kind; because horses which agree in whiteness do not agree in anything else, except the qualities common to all horses, and whatever may be the causes or effects of that particular colour.

On the principle that there should be a name for everything which we have frequent occasion to make assertions about, there ought evidently to be a name for every Kind; for as it is the very meaning of a Kind that the individuals composing it have an indefinite multitude of properties in common, it follows that, if not with our present knowledge, yet with that which we may hereafter acquire, the Kind is a subject to which there will have to be applied many predicates. The third component element of a philosophical language, therefore, is that there shall be a name for every Kind. In other words, there must not only be a terminology, but also a nomenclature,

A nomenclature may be defined, the collection of the names of all the Kinds with which any branch of knowledge is conversant; or more properly, of all the lowest Kinds, or infimæ species-those which may be subdivided indeed, but not into Kinds, and which generally accord with what in natural history are termed simply species. Science possesses two splendid examples of a systematic nomenclature; that of plants and animals, constructed by Linnæus and his successors, and that of chemistry, which we owe to the illustrious_group of chemists who flourished in France towards the close of the eighteenth century. In these two departments, not only has every known species, or lowest Kind, a name assigned to it, but when new lowest Kinds are discovered, names are at once given to them on an uniform principle. In other sciences the nomenclature is not at present constructed on any system, either because the species to be named are not