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Sophist

In all the later dialogues of Plato, the idea of mind or intelligence becomes more and more prominent. That idea which Anaxagoras employed inconsistently in the construction of the world, Plato, in the Philebus, the Sophist, and the Laws, extends to all things, attributing to Providence a care, infinitesimal as well as infinite, of all creation. The divine mind is the leading religious thought of the later works of Plato. The human mind is a sort of reflection of this, having ideas of Being, Sameness, and the like. At times they seem to be parted by a great gulf (Parmenides); at other times they have a common nature, and the light of a common intelligence.

But this ever-growing idea of mind is really irreconcilable with the abstract Pantheism of the Eleatics. To the passionate language of Parmenides, Plato replies in a strain equally passionate: – What! has not Being mind? and is not Being capable of being known? and, if this is admitted, then capable of being affected or acted upon? – in motion, then, and yet not wholly incapable of rest. Already we have been compelled to attribute opposite determinations to Being. And the answer to the difficulty about Being may be equally the answer to the difficulty about Not-being.

The answer is, that in these and all other determinations of any notion we are attributing to it 'Not-being.' We went in search of Not-being and seemed to lose Being, and now in the hunt after Being we recover both. Not-being is a kind of Being, and in a sense co-extensive with Being. And there are as many divisions of Not-being as of Being. To every positive idea – 'just,' 'beautiful,' and the like, there is a corresponding negative idea – 'not-just,' 'not-beautiful,' and the like.

A doubt may be raised whether this account of the negative is really the true one. The common logicians would say that the 'not-just,' 'not-beautiful,' are not really classes at all, but are merged in one great class of the infinite or negative. The conception of Plato, in the days before logic, seems to be more correct than this. For the word 'not' does not altogether annihilate the positive meaning of the word 'just': at least, it does not prevent our looking for the 'not-just' in or about the same class in which we might expect to find the 'just.' 'Not-just is not-honourable' is neither a false nor an unmeaning proposition. The reason is that the negative proposition has really passed into an undefined positive. To say that 'not-just' has no more meaning than 'not-honourable' – that is to say, that the two cannot in any degree be distinguished, is clearly repugnant to the common use of language.

The ordinary logic is also jealous of the explanation of negation as relation, because seeming to take away the principle of contradiction. Plato, as far as we know, is the first philosopher who distinctly enunciated this principle; and though we need not suppose him to have been always consistent with himself, there is no real inconsistency between his explanation of the negative and the principle of contradiction. Neither the Platonic notion of the negative as the principle of difference, nor the Hegelian identity of Being and Not-being, at all touch the principle of contradiction. For what is asserted about Being and Not-Being only relates to our most abstract notions, and in no way interferes with the principle of contradiction employed in the concrete. Because Not-being is identified with Other, or Being with Not-being, this does not make the proposition 'Some have not eaten' any the less a contradiction of 'All have eaten.'

The explanation of the negative given by Plato in the Sophist is a true but partial one; for the word 'not,' besides the meaning of 'other,' may also imply 'opposition.' And difference or opposition may be either total or partial: the not-beautiful may be other than the beautiful, or in no relation to the beautiful, or a specific class in various degrees opposed to the beautiful. And the negative may be a negation of fact or of thought (ou and me). Lastly, there are certain ideas, such as 'beginning,' 'becoming,' 'the finite,' 'the abstract,' in which the negative cannot be separated from the positive, and 'Being' and 'Not-being' are inextricably blended.

Plato restricts the conception of Not-being to difference. Man is a rational animal, and is not – as many other things as are not included under this definition. He is and is not, and is because he is not. Besides the positive class to which he belongs, there are endless negative classes to which he may be referred. This is certainly intelligible, but useless. To refer a subject to a negative class is unmeaning, unless the 'not' is a mere modification of the positive, as in the example of 'not honourable' and 'dishonourable'; or unless the class is characterized by the absence rather than the presence of a particular quality.

Nor is it easy to see how Not-being any more than Sameness or Otherness is one of the classes of Being. They are aspects rather than classes of Being. Not-being can only be included in Being, as the denial of some particular class of Being. If we attempt to pursue such airy phantoms at all, the Hegelian identity of Being and Not-being is a more apt and intelligible expression of the same mental phenomenon. For Plato has not distinguished between the Being which is prior to Not-being, and the Being which is the negation of Not-being (compare Parm.).

But he is not thinking of this when he says that Being comprehends Not-being. Again, we should probably go back for the true explanation to the influence which the Eleatic philosophy exercised over him. Under 'Not-being' the Eleatic had included all the realities of the sensible world. Led by this association and by the common use of language, which has been already noticed, we cannot be much surprised that Plato should have made classes of Not-being. It is observable that he does not absolutely deny that there is an opposite of Being. He is inclined to leave the question, merely remarking that the opposition, if admissible at all, is not expressed by the term 'Not-being.'

On the whole, we must allow that the great service rendered by Plato to metaphysics in the Sophist, is not his explanation of 'Not-being' as difference. With this he certainly laid the ghost of 'Not-being'; and we may attribute to him in a measure the credit of anticipating Spinoza and Hegel. But his conception is not clear or consistent; he does not recognize the different senses of the negative, and he confuses the different classes of Not-being with the abstract notion. As the Pre-Socratic philosopher failed to distinguish between the universal and the true, while he placed the particulars of sense under the false and apparent, so Plato appears to identify negation with falsehood, or is unable to distinguish them. The greatest service rendered by him to mental science is the recognition of the communion of classes, which, although based by him on his account of 'Not-being,' is independent of it. He clearly saw that the isolation of ideas or classes is the annihilation of reasoning. Thus, after wandering in many diverging paths, we return to common sense. And for this reason we may be inclined to do less than justice to Plato, – because the truth which he attains by a real effort of thought is to us a familiar and unconscious truism, which no one would any longer think either of doubting or examining.

IV. The later dialogues of Plato contain many references to contemporary philosophy. Both in the Theaetetus and in the Sophist he recognizes that he is in the midst of a fray; a huge irregular battle everywhere surrounds him (Theaet.). First, there are the two great philosophies going back into cosmogony and poetry: the philosophy of Heracleitus, supposed to have a poetical origin in Homer, and that of the Eleatics, which in a similar spirit he conceives to be even older than Xenophanes (compare Protag.). Still older were theories of two and three principles, hot and cold, moist and dry, which were ever marrying and being given in marriage: in speaking of these, he is probably referring to Pherecydes and the early Ionians. In the philosophy of motion there were different accounts of the relation of plurality and unity, which were supposed to be joined and severed by love and hate, some maintaining that this process was perpetually going on (e.g. Heracleitus); others (e.g. Empedocles) that there was an alternation of them. Of the Pythagoreans or of Anaxagoras he makes no distinct mention. His chief opponents are, first, Eristics or Megarians; secondly, the Materialists.

The picture which he gives of both these latter schools is indistinct; and he appears reluctant to mention the names of their teachers. Nor can we easily determine how much is to be assigned to the Cynics, how much to the Megarians, or whether the 'repellent Materialists' (Theaet.) are Cynics or Atomists, or represent some unknown phase of opinion at Athens. To the Cynics and Antisthenes is commonly attributed, on the authority of Aristotle, the denial of predication, while the Megarians are said to have been Nominalists, asserting the One Good under many names to be the true Being of Zeno and the Eleatics, and, like Zeno, employing their negative dialectic in the refutation of opponents. But the later Megarians also denied predication; and this tenet, which is attributed to all of them by Simplicius, is certainly in accordance with their over-refining philosophy. The 'tyros young and old,' of whom Plato speaks, probably include both. At any rate, we shall be safer in accepting the general description of them which he has given, and in not attempting to draw a precise line between them.

Of these Eristics, whether Cynics or Megarians, several characteristics are found in Plato: —

1. They pursue verbal oppositions; 2. they make reasoning impossible by their over-accuracy in the use of language; 3. they deny predication; 4. they go from unity to plurality, without passing through the intermediate stages; 5. they refuse to attribute motion or power to Being; 6. they are the enemies of sense; – whether they are the 'friends of ideas,' who carry on the polemic against sense, is uncertain; probably under this remarkable expression Plato designates those who more nearly approached himself, and may be criticizing an earlier form of his own doctrines. We may observe (1) that he professes only to give us a few opinions out of many which were at that time current in Greece; (2) that he nowhere alludes to the ethical teaching of the Cynics – unless the argument in the Protagoras, that the virtues are one and not many, may be supposed to contain a reference to their views, as well as to those of Socrates; and unless they are the school alluded to in the Philebus, which is described as 'being very skilful in physics, and as maintaining pleasure to be the absence of pain.' That Antisthenes wrote a book called 'Physicus,' is hardly a sufficient reason for describing them as skilful in physics, which appear to have been very alien to the tendency of the Cynics.

The Idealism of the fourth century before Christ in Greece, as in other ages and countries, seems to have provoked a reaction towards Materialism. The maintainers of this doctrine are described in the Theaetetus as obstinate persons who will believe in nothing which they cannot hold in their hands, and in the Sophist as incapable of argument. They are probably the same who are said in the Tenth Book of the Laws to attribute the course of events to nature, art, and chance. Who they were, we have no means of determining except from Plato's description of them. His silence respecting the Atomists might lead us to suppose that here we have a trace of them. But the Atomists were not Materialists in the grosser sense of the term, nor were they incapable of reasoning; and Plato would hardly have described a great genius like Democritus in the disdainful terms which he uses of the Materialists. Upon the whole, we must infer that the persons here spoken of are unknown to us, like the many other writers and talkers at Athens and elsewhere, of whose endless activity of mind Aristotle in his Metaphysics has preserved an anonymous memorial.

V. The Sophist is the sequel of the Theaetetus, and is connected with the Parmenides by a direct allusion (compare Introductions to Theaetetus and Parmenides). In the Theaetetus we sought to discover the nature of knowledge and false opinion. But the nature of false opinion seemed impenetrable; for we were unable to understand how there could be any reality in Not-being. In the Sophist the question is taken up again; the nature of Not-being is detected, and there is no longer any metaphysical impediment in the way of admitting the possibility of falsehood. To the Parmenides, the Sophist stands in a less defined and more remote relation. There human thought is in process of disorganization; no absurdity or inconsistency is too great to be elicited from the analysis of the simple ideas of Unity or Being. In the Sophist the same contradictions are pursued to a certain extent, but only with a view to their resolution. The aim of the dialogue is to show how the few elemental conceptions of the human mind admit of a natural connexion in thought and speech, which Megarian or other sophistry vainly attempts to deny.

…

True to the appointment of the previous day, Theodorus and Theaetetus meet Socrates at the same spot, bringing with them an Eleatic Stranger, whom Theodorus introduces as a true philosopher. Socrates, half in jest, half in earnest, declares that he must be a god in disguise, who, as Homer would say, has come to earth that he may visit the good and evil among men, and detect the foolishness of Athenian wisdom. At any rate he is a divine person, one of a class who are hardly recognized on earth; who appear in divers forms – now as statesmen, now as sophists, and are often deemed madmen. 'Philosopher, statesman, sophist,' says Socrates, repeating the words – 'I should like to ask our Eleatic friend what his countrymen think of them; do they regard them as one, or three?'

The Stranger has been already asked the same question by Theodorus and Theaetetus; and he at once replies that they are thought to be three; but to explain the difference fully would take time. He is pressed to give this fuller explanation, either in the form of a speech or of question and answer. He prefers the latter, and chooses as his respondent Theaetetus, whom he already knows, and who is recommended to him by Socrates.

We are agreed, he says, about the name Sophist, but we may not be equally agreed about his nature. Great subjects should be approached through familiar examples, and, considering that he is a creature not easily caught, I think that, before approaching him, we should try our hand upon some more obvious animal, who may be made the subject of logical experiment; shall we say an angler? 'Very good.'

In the first place, the angler is an artist; and there are two kinds of art, – productive art, which includes husbandry, manufactures, imitations; and acquisitive art, which includes learning, trading, fighting, hunting. The angler's is an acquisitive art, and acquisition may be effected either by exchange or by conquest; in the latter case, either by force or craft. Conquest by craft is called hunting, and of hunting there is one kind which pursues inanimate, and another which pursues animate objects; and animate objects may be either land animals or water animals, and water animals either fly over the water or live in the water. The hunting of the last is called fishing; and of fishing, one kind uses enclosures, catching the fish in nets and baskets, and another kind strikes them either with spears by night or with barbed spears or barbed hooks by day; the barbed spears are impelled from above, the barbed hooks are jerked into the head and lips of the fish, which are then drawn from below upwards. Thus, by a series of divisions, we have arrived at the definition of the angler's art.

And now by the help of this example we may proceed to bring to light the nature of the Sophist. Like the angler, he is an artist, and the resemblance does not end here. For they are both hunters, and hunters of animals; the one of water, and the other of land animals. But at this point they diverge, the one going to the sea and the rivers, and the other to the rivers of wealth and rich meadow-lands, in which generous youth abide. On land you may hunt tame animals, or you may hunt wild animals. And man is a tame animal, and he may be hunted either by force or persuasion; – either by the pirate, man-stealer, soldier, or by the lawyer, orator, talker. The latter use persuasion, and persuasion is either private or public. Of the private practitioners of the art, some bring gifts to those whom they hunt: these are lovers. And others take hire; and some of these flatter, and in return are fed; others profess to teach virtue and receive a round sum. And who are these last? Tell me who? Have we not unearthed the Sophist?

But he is a many-sided creature, and may still be traced in another line of descent. The acquisitive art had a branch of exchange as well as of hunting, and exchange is either giving or selling; and the seller is either a manufacturer or a merchant; and the merchant either retails or exports; and the exporter may export either food for the body or food for the mind. And of this trading in food for the mind, one kind may be termed the art of display, and another the art of selling learning; and learning may be a learning of the arts or of virtue. The seller of the arts may be called an art-seller; the seller of virtue, a Sophist.

Again, there is a third line, in which a Sophist may be traced. For is he less a Sophist when, instead of exporting his wares to another country, he stays at home, and retails goods, which he not only buys of others, but manufactures himself?

Or he may be descended from the acquisitive art in the combative line, through the pugnacious, the controversial, the disputatious arts; and he will be found at last in the eristic section of the latter, and in that division of it which disputes in private for gain about the general principles of right and wrong.

And still there is a track of him which has not yet been followed out by us. Do not our household servants talk of sifting, straining, winnowing? And they also speak of carding, spinning, and the like. All these are processes of division; and of division there are two kinds, – one in which like is divided from like, and another in which the good is separated from the bad. The latter of the two is termed purification; and again, of purification, there are two sorts, – of animate bodies (which may be internal or external), and of inanimate. Medicine and gymnastic are the internal purifications of the animate, and bathing the external; and of the inanimate, fulling and cleaning and other humble processes, some of which have ludicrous names. Not that dialectic is a respecter of names or persons, or a despiser of humble occupations; nor does she think much of the greater or less benefits conferred by them. For her aim is knowledge; she wants to know how the arts are related to one another, and would quite as soon learn the nature of hunting from the vermin-destroyer as from the general. And she only desires to have a general name, which shall distinguish purifications of the soul from purifications of the body.

Now purification is the taking away of evil; and there are two kinds of evil in the soul, – the one answering to disease in the body, and the other to deformity. Disease is the discord or war of opposite principles in the soul; and deformity is the want of symmetry, or failure in the attainment of a mark or measure. The latter arises from ignorance, and no one is voluntarily ignorant; ignorance is only the aberration of the soul moving towards knowledge. And as medicine cures the diseases and gymnastic the deformity of the body, so correction cures the injustice, and education (which differs among the Hellenes from mere instruction in the arts) cures the ignorance of the soul. Again, ignorance is twofold, simple ignorance, and ignorance having the conceit of knowledge. And education is also twofold: there is the old-fashioned moral training of our forefathers, which was very troublesome and not very successful; and another, of a more subtle nature, which proceeds upon a notion that all ignorance is involuntary. The latter convicts a man out of his own mouth, by pointing out to him his inconsistencies and contradictions; and the consequence is that he quarrels with himself, instead of quarrelling with his neighbours, and is cured of prejudices and obstructions by a mode of treatment which is equally entertaining and effectual. The physician of the soul is aware that his patient will receive no nourishment unless he has been cleaned out; and the soul of the Great King himself, if he has not undergone this purification, is unclean and impure.

And who are the ministers of the purification? Sophists I may not call them. Yet they bear about the same likeness to Sophists as the dog, who is the gentlest of animals, does to the wolf, who is the fiercest. Comparisons are slippery things; but for the present let us assume the resemblance of the two, which may probably be disallowed hereafter. And so, from division comes purification; and from this, mental purification; and from mental purification, instruction; and from instruction, education; and from education, the nobly-descended art of Sophistry, which is engaged in the detection of conceit. I do not however think that we have yet found the Sophist, or that his will ultimately prove to be the desired art of education; but neither do I think that he can long escape me, for every way is blocked. Before we make the final assault, let us take breath, and reckon up the many forms which he has assumed: (1) he was the paid hunter of wealth and birth; (2) he was the trader in the goods of the soul; (3) he was the retailer of them; (4) he was the manufacturer of his own learned wares; (5) he was the disputant; and (6) he was the purger away of prejudices – although this latter point is admitted to be doubtful.

Now, there must surely be something wrong in the professor of any art having so many names and kinds of knowledge. Does not the very number of them imply that the nature of his art is not understood? And that we may not be involved in the misunderstanding, let us observe which of his characteristics is the most prominent. Above all things he is a disputant. He will dispute and teach others to dispute about things visible and invisible – about man, about the gods, about politics, about law, about wrestling, about all things. But can he know all things? 'He cannot.' How then can he dispute satisfactorily with any one who knows? 'Impossible.' Then what is the trick of his art, and why does he receive money from his admirers? 'Because he is believed by them to know all things.' You mean to say that he seems to have a knowledge of them? 'Yes.'

Suppose a person were to say, not that he would dispute about all things, but that he would make all things, you and me, and all other creatures, the earth and the heavens and the gods, and would sell them all for a few pence – this would be a great jest; but not greater than if he said that he knew all things, and could teach them in a short time, and at a small cost. For all imitation is a jest, and the most graceful form of jest. Now the painter is a man who professes to make all things, and children, who see his pictures at a distance, sometimes take them for realities: and the Sophist pretends to know all things, and he, too, can deceive young men, who are still at a distance from the truth, not through their eyes, but through their ears, by the mummery of words, and induce them to believe him. But as they grow older, and come into contact with realities, they learn by experience the futility of his pretensions. The Sophist, then, has not real knowledge; he is only an imitator, or image-maker.

And now, having got him in a corner of the dialectical net, let us divide and subdivide until we catch him. Of image-making there are two kinds, – the art of making likenesses, and the art of making appearances. The latter may be illustrated by sculpture and painting, which often use illusions, and alter the proportions of figures, in order to adapt their works to the eye. And the Sophist also uses illusions, and his imitations are apparent and not real. But how can anything be an appearance only? Here arises a difficulty which has always beset the subject of appearances. For the argument is asserting the existence of not-being. And this is what the great Parmenides was all his life denying in prose and also in verse. 'You will never find,' he says, 'that not-being is.' And the words prove themselves! Not-being cannot be attributed to any being; for how can any being be wholly abstracted from being? Again, in every predication there is an attribution of singular or plural. But number is the most real of all things, and cannot be attributed to not-being. Therefore not-being cannot be predicated or expressed; for how can we say 'is,' 'are not,' without number?

And now arises the greatest difficulty of all. If not-being is inconceivable, how can not-being be refuted? And am I not contradicting myself at this moment, in speaking either in the singular or the plural of that to which I deny both plurality and unity? You, Theaetetus, have the might of youth, and I conjure you to exert yourself, and, if you can, to find an expression for not-being which does not imply being and number. 'But I cannot.' Then the Sophist must be left in his hole. We may call him an image-maker if we please, but he will only say, 'And pray, what is an image?' And we shall reply, 'A reflection in the water, or in a mirror'; and he will say, 'Let us shut our eyes and open our minds; what is the common notion of all images?' 'I should answer, Such another, made in the likeness of the true.' Real or not real? 'Not real; at least, not in a true sense.' And the real 'is,' and the not-real 'is not'? 'Yes.' Then a likeness is really unreal, and essentially not. Here is a pretty complication of being and not-being, in which the many-headed Sophist has entangled us. He will at once point out that he is compelling us to contradict ourselves, by affirming being of not-being. I think that we must cease to look for him in the class of imitators.

But ought we to give him up? 'I should say, certainly not.' Then I fear that I must lay hands on my father Parmenides; but do not call me a parricide; for there is no way out of the difficulty except to show that in some sense not-being is; and if this is not admitted, no one can speak of falsehood, or false opinion, or imitation, without falling into a contradiction. You observe how unwilling I am to undertake the task; for I know that I am exposing myself to the charge of inconsistency in asserting the being of not-being. But if I am to make the attempt, I think that I had better begin at the beginning.

Lightly in the days of our youth, Parmenides and others told us tales about the origin of the universe: one spoke of three principles warring and at peace again, marrying and begetting children; another of two principles, hot and cold, dry and moist, which also formed relationships. There were the Eleatics in our part of the world, saying that all things are one; whose doctrine begins with Xenophanes, and is even older. Ionian, and, more recently, Sicilian muses speak of a one and many which are held together by enmity and friendship, ever parting, ever meeting. Some of them do not insist on the perpetual strife, but adopt a gentler strain, and speak of alternation only. Whether they are right or not, who can say? But one thing we can say – that they went on their way without much caring whether we understood them or not. For tell me, Theaetetus, do you understand what they mean by their assertion of unity, or by their combinations and separations of two or more principles? I used to think, when I was young, that I knew all about not-being, and now I am in great difficulties even about being.

Let us proceed first to the examination of being. Turning to the dualist philosophers, we say to them: Is being a third element besides hot and cold? or do you identify one or both of the two elements with being? At any rate, you can hardly avoid resolving them into one. Let us next interrogate the patrons of the one. To them we say: Are being and one two different names for the same thing? But how can there be two names when there is nothing but one? Or you may identify them; but then the name will be either the name of nothing or of itself, i.e. of a name. Again, the notion of being is conceived of as a whole – in the words of Parmenides, 'like every way unto a rounded sphere.' And a whole has parts; but that which has parts is not one, for unity has no parts. Is being, then, one, because the parts of being are one, or shall we say that being is not a whole? In the former case, one is made up of parts; and in the latter there is still plurality, viz. being, and a whole which is apart from being. And being, if not all things, lacks something of the nature of being, and becomes not-being. Nor can being ever have come into existence, for nothing comes into existence except as a whole; nor can being have number, for that which has number is a whole or sum of number. These are a few of the difficulties which are accumulating one upon another in the consideration of being.

We may proceed now to the less exact sort of philosophers. Some of them drag down everything to earth, and carry on a war like that of the giants, grasping rocks and oaks in their hands. Their adversaries defend themselves warily from an invisible world, and reduce the substances of their opponents to the minutest fractions, until they are lost in generation and flux. The latter sort are civil people enough; but the materialists are rude and ignorant of dialectics; they must be taught how to argue before they can answer. Yet, for the sake of the argument, we may assume them to be better than they are, and able to give an account of themselves. They admit the existence of a mortal living creature, which is a body containing a soul, and to this they would not refuse to attribute qualities – wisdom, folly, justice and injustice. The soul, as they say, has a kind of body, but they do not like to assert of these qualities of the soul, either that they are corporeal, or that they have no existence; at this point they begin to make distinctions. 'Sons of earth,' we say to them, 'if both visible and invisible qualities exist, what is the common nature which is attributed to them by the term "being" or "existence"?' And, as they are incapable of answering this question, we may as well reply for them, that being is the power of doing or suffering. Then we turn to the friends of ideas: to them we say, 'You distinguish becoming from being?' 'Yes,' they will reply. 'And in becoming you participate through the bodily senses, and in being, by thought and the mind?' 'Yes.' And you mean by the word 'participation' a power of doing or suffering? To this they answer – I am acquainted with them, Theaetetus, and know their ways better than you do – that being can neither do nor suffer, though becoming may. And we rejoin: Does not the soul know? And is not 'being' known? And are not 'knowing' and 'being known' active and passive? That which is known is affected by knowledge, and therefore is in motion. And, indeed, how can we imagine that perfect being is a mere everlasting form, devoid of motion and soul? for there can be no thought without soul, nor can soul be devoid of motion. But neither can thought or mind be devoid of some principle of rest or stability. And as children say entreatingly, 'Give us both,' so the philosopher must include both the moveable and immoveable in his idea of being. And yet, alas! he and we are in the same difficulty with which we reproached the dualists; for motion and rest are contradictions – how then can they both exist? Does he who affirms this mean to say that motion is rest, or rest motion? 'No; he means to assert the existence of some third thing, different from them both, which neither rests nor moves.' But how can there be anything which neither rests nor moves? Here is a second difficulty about being, quite as great as that about not-being. And we may hope that any light which is thrown upon the one may extend to the other.