Classics in the History of Psychology

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Definitions Le - Loc

Posted July 2001

Leading of Proof: no concise foreign equivalents. The operation bringing up to attention, among propositions admitted to be true, certain relations between them which logically compel the acceptance of a conclusion. (C.S.P.)

Leading Principle: Ger. leitendes Prinzip; Fr. principe directeur; Ital. principio fondamentale. It is of the essence of reasoning that the reasoner should proceed, and should be conscious of proceeding, according to a general habit, or method, which he holds would either (according to the kind of reasoning) always lead to the truth, provided the premises were true; or, consistently adhered to, would eventually approximate indefinitely to the truth; or would be generally conducive to the ascertainment of truth, supposing there be any ascertainable truth. The effect of this habit or method could be stated in a proposition of which the antecedent should describe all possible premises upon which it could operate, while the consequent should describe how the conclusion to which it would lead would be determinately related to those premises. Such a proposition is called the 'leading principle' of the reasoning.

Two different reasoners might infer the same conclusion from the same premises; and yet their proceeding might be governed by habits which would be formulated in different, or even conflicting, leading principles. Only that man's reasoning would be good whose leading principle was true for all possible cases. It is not essential that the reasoner should have a distinct apprehension of the leading principle of the habit which governs his reasoning; it is sufficient that he should be conscious of proceeding according to a general method, and that he should hold that that method is generally apt to lead to the truth. He may even conceive himself to be following one leading principle when, in reality, he is following another, and may consequently blunder in his conclusion. From the effective leading principle, together with the premises, the propriety of accepting the conclusion in such sense as it is accepted follows necessarily in every case. Suppose that the leading principle involves two propositions, L and L', and suppose that there are three premises, P, P', P''; and let C signify the acceptance of the conclusion, as it is accepted, either as true, or as a legitimate approximation to the truth, or as an assumption conducive to the ascertainment of the truth. Then, from the five premises L, L', P, P', P'', the inference to C would be necessary; but it would not be so from L, L', P', P'' alone, for, if it were, P would not really act as a premise at all. >From P' and P'' as the sole premises, C would follow, if the leading principle consisted of L, L', and P. Or from the four premises L', P, P', P'', the same conclusion would follow if L alone were the leading principle. What, then, could be the leading principle of the inference of C from all five propositions L, L', P, P', P'', taken as premises? It would be something already implied in those premises; and it might be almost any general proposition so implied. Leading principles are, therefore, of two classes; and any leading principle whose truth is implied in the premises of every inference which it governs is called a 'logical' (or, less appropriately, a formal) leading principle; while a leading principle whose truth is not implied in the premises is called a 'factual' (or material) leading principle. (C.S.P.)

Least Squares (method of): see ERRORS of OBSERVATION.

Left-handedness: see DEXTRALITY.

Legal [Lat. legalis]: Ger. gesetzlich; Fr. légal; Ital. legale. (1) Pertaining to law. (2) Conformable to law. (3) Pertaining to law, as distinguished from equity. (4) Defined or created by law, e.g. legal offences, legal disabilities.

Legal defence: one sufficient under the rules of law. Legal ethics: the ethical rules governing the conduct of the legal profession. That may be legal which is neither just nor honourable. 'Non omne quod licet honestum est,' Dig., 1. 17, de diversis regulis iuris antiqui, 144. (S.E.B.)

Legal Fiction: Ger. Rechtsfiction; Fr. fiction légale; Ital. finzione legale. The assumption, as a fact, of what is not known to be such, made by authority of law to promote justice.

It is generally done by the courts, sometimes by the legislature. Thus the English courts of common law, in order to take jurisdiction of matters of admiralty jurisdiction, anciently allowed a plaintiff to describe his cause of action as arising at Havre, to wit, in Westminster, and refused to allow the defendant to contest their right to entertain the case by denying the averment as to Westminster. Cf. Maine's Ancient Law, 26.

Legal fictions furnish the means by which most nations develop their system of procedure from formal into rational methods. See, as to their use in Roman law, Sohm's Inst. of Roman Law, § 38; Hadley's Introd. to Roman Law, 96. Wills causelessly disinheriting children could be set aside, 'hoc colore, quasi non sanae mentis fuerint cum testamenta ordinarent. Sed hoc dicitur non quasi vere furiosus sit, sed recte quidem fecerit testamentum, non autem ex officio pietatis. Nam si vere furiosus sit, nullum testamentum est' (Inst. of Just., ii. 18, de inofficioso testamento). (S.E.B.)

Legend [Lat. legere, to read]: Ger. Legende; Fr. légende; Ital. leggenda. An edifying tradition which has grown up spontaneously and uncritically around some historical personage, and which, though lacking in historic verity, is valuable in the revelation it makes of the spirit and life of the people and time that produced it.

In ecclesiastical history: legend is the story of a saint or other religious personage which has grown up gradually in response to the requirements of religious edification, and which, though containing a nucleus of truth, is not historically reliable.

The legend differs from the myth in that it ordinarily develops about a real personage, whereas the myth may be pure fiction, and ordinarily arises out of a personification of some natural object or force. See MYTH.

Literature: EHRET, Allg. Gesch. d. Literatur d. Mittelalters im Abendlande (1874-87); MILMAN, Hist. of Latin Christianity; LECKY, Hist. of Rationalism in Europe. (A.T.O.)

Legislation [Lat. lex, law, + latio, a proposing]: Ger. Gesetzgebung; Fr. législation; Ital. legislazione. (1) The act of making a law, by a legislator or legislature. 'In legislation both contents of the rule are devised, and legal force is given to it, by simultaneous acts of the sovereign power which produce "written law." All the other law sources produce what is called "unwritten law," to which the sovereign authority gives its whole legal force, but not its contents, which are derived from popular tendency, professional discussion, judicial ingenuity, or otherwise, as the case may be' (Holland, Jurisprudence, chap. v. 66). (2) The law made by a legislator or legislature.

Judicial legislation: the virtual making of law by judicial magistrates, by declaring in their judgments that to be law which had not previously been enacted or generally recognized as such. (S.E.B.)

Legitimate (in law) [Med. Lat. legitimatus]: Ger. gesetzmässig, legitim; Fr. légitime; Ital. legittimo. Accordant with law; having the support of law; legally entitled, especially of a child born in lawful wedlock (whether begotten in wedlock or not).

Legitimate portion: that share of a parent's estate which, by the rules of the civil law, cannot be willed away from the natural heir without some recognized legal justification. (S.E.B.)

Legitimation [Fr.]: Ger. Legitimation; Fr. légitimation; Ital. legittimazione. That by which an illegitimate child is made legitimate in law.

By English and American common law there is no method of legitimation. The later Roman law allowed it by virtue of a marriage of the parents at any time after the conception or the birth of the child (Inst. of Just., iii. 1, 2). Similar laws have been enacted in many of the United States.

By English common law, legitimation has no extra-territorial force. Cf. Wharton, Private Int. Law, chap. v. (S.E.B.)

Leibnitz (or Leibniz), Baron Gottfried Wilhelm von. (1646-1716.) Born at Leipzig, where his father was professor of ethics, he was educated at Leipzig and Jena Universities. He received a doctorate in law, but had become deeply read in scholasticism and logic. For a period he had also studied Bacon, Hobbes, Kepler, Galilei, Gassendi, and, to some extent, Descartes; and was for a time converted to the mathematico-mechanical conception of nature. Under the patronage of Baron Boineburg he prepared for a political life, became assistant to Lasser in the preparation of a reformed code of Roman law, and member of the Court of Appeals in Mainz (1670). He visited London, met Newton, Boyle, and others, and became Fellow of the Royal Society. In Paris he was intimate with Cassini and Huyghens. In 1676 he accepted a position in the court of the Duke of Brunswick-Lüneburg, and (1678) was made counsellor and member of the supreme court. Called to Berlin in 1698 by Princess Sophia Charlotte, he established the Scientific Society, which has since become Berlin University.

Lemma [Gr. lhmma, gain, an assumption, premise]: Ger. Hülfssatz, Lehnsatz; Fr. lemme; Ital. lemma. A theorem which interrupts the course of development of a mathematical theory, but which is inserted to supply a premise for one of the theorems.

This use of the word seems to go back to Euclid, at least; and even Aristotle uses the word -- not a common one with him -- in connection with geometry, in the first chapter of the Topics. With Aristotle, however, it means a premise; and with the Stoics, more particularly, the major premise of a syllogism. (C.S.P.)

Lese-majesty [Fr.], also written 'leze-majesty': Ger. Majestätsbeleidigung, Hochverrat; Fr. lèse-majesté; Ital. lesa maestà. The crime of direct attack on the state, or on its sovereign, his family, or his chief officers of government.

Formerly in Europe this crime was also regarded as comprehending offences committed directly against God, such as sacrilege, blasphemy, or apostasy; being thus termed lèse-majesté, divine (Merlin's Répertoire de Jurisprudence, sub verbo). Of lèse-majesté humaine there were several degrees, the offence being pushed so far in France as to include embezzlement by public officials and unlawful assemblies. The crime of HIGH TREASON (q.v.) was known by this name in England in the time of Glanvil (12th century). The Roman law named this offence maiestatis crimen or more fully 'crimen laesae, imminutae, diminutae, minutae, maiestatis,' Dig., x1viii. 4, ad Legem Iuliam Maiestatis; Smith's Dict. of Greek and Roman Antiq. (maiestas); Heineccius, Antiq. Rom. Syntagma, iv. § 46 f.) (S.E.B.)

Lessing, Gotthold Ephraim. (1729-81.) Educated at the Fürst nschule in Meissen, and at Leipzig, in philology and theology. After 1748 he spent some time as journalist in Berlin. Went to Wittenberg (1752) to complete his studies; returned to Berlin (1753) to resume his work as journalist and critic. After two years spent in Leipzig, he returned once more (1758) to Berlin. In 1760 he became secretary to General von Tauenzien in Beslau, during the Seven Years' War; 1767, official playwright and artistic director of the Hamburg theatre; 1770, librarian of the ducal library at Wolfenbüttel.

Lewes, George Henry. (1817-78.) An English Positivist, born in London. In youth a business clerk, he began the study of medicine, but abandoned it for philosophy and psychology. Spent two years in Germany, returning to London in 1840, and devoting himself to literature. He was literary editor of The Leader (1849-54), and founded the Fortnightly Review.

Liability (in law) [Fr. lier, from Lat. legare, to bind]: Ger. Haftbarkeit; Fr. responsabilité; Ital. risponsabilità. Such a relation by one to another as will or may support an action by the latter against the former.

The maker of a note, as soon as it is delivered, comes under a liability to the holder, which may support an action, and will, if the note be dishonoured when due. The contingent liability of the endorser of a note becomes an absolute liability when the note is dishonoured, and due demand and notice follow. Liability is viewed by Austin 'as a sanction' imposed by law as a penalty for disobedience of law. But an unintentional act of violence to another may impose an actionable liability, though there was no intent to disobey the law. Liability for an act whereby another is injured can be rested better on the natural obligation to act in contemplation of the natural tendency, under existing circumstances known or knowable, of the act to do harm (see Holmes on the Common Law, 79, 81, 162).

Limited liability: (1) a liability of shareholders in a business corporation or joint-stock company, limited by law to the amount of their subscriptions for shares; (2) the restricted liability of shipowners for accidents occurring without their fault (see U.S. Revised Statutes, § 832). Individual liability: that which one holding a representative position as executor, cashier, or governor, may incur by contracting on his personal credit, though not for his personal benefit. The common-law maxim is Ubi ius, ibi remedium. (S.E.B.)

Libelt, Karol. (1807-75.) Educated at Berlin, under Hegel, in philosophy. Wrote the gold medal essay on Spinoza (1828); received his doctorate in philosophy (1830). Took part in the Polish revolution in that year, and was imprisoned nine months. In 1840 he opened a private school at Posen, and edited two journals. His life was given to literature. He was again imprisoned (1846-8), and his journal suppressed (1849). Took a prominent part in the reorganization of Great Poland, and protested in the Parliament at Frankfort against the incorporation of Great Poland in Germany. He was the first famous Polish philosopher.

Liberalism [Lat. liber, free]: Ger. Liberalismus; Fr. libéralisme; Ital. liberalismo. (1) The personal disposition to free and untrammelled thought and action.

(2) The social sentiment which welcomes reforming and progressive opinion and action.

Liberalism is opposed to conservatism in both these meanings; but a certain relative balance between them is necessary to stable social organization, in which the writer (Social and Eth. Interpret., chap. v. § 3; cf. Royce, Psychol. Rev., v. 1898, 113) has likened them to habit and accommodation in the individual's life. Extreme liberalism, taking the form of a disposition to accept innovations as such, is called radicalism.

Literature: see SOCIOLOGY, and SOCIAL PSYCHOLOGY. (J.M.B., F.H.G.)

Liberty (1) and (2) Libertarianism [Lat. libertas]: Ger. Freiheit; Fr. liberté; Ital. libertà. (1) See FREEDOM (various meanings), and WILL; (2) Ethical INDETERMINISM (q.v.), also the references made under (1). (J.M.B.)

Liberty (political): see FREEDOM (political and social).

Liberty (religious): Ger. Religionsfreiheit; Fr. liberté religieuse; Ital. libertà religiosa. The legally secured right of the individual to hold and practise without interference any form of religious belief and worship he may choose, in so far as the exercise of his prerogative does not conflict with the fundamental political and social principles of the society to which he belongs.

The history of religious liberty in modern times begins with the edict of toleration by Constantine in 313 A.D. Throughout the middle ages the enforcement of conformity to prescribed form of belief was regarded as a duty. The Reformation did not effect much advance in freedom, but Catholic and Protestant alike claimed the right of coercion. A considerable advance was made at the Peace of Westphalia in 1648, when equal rights were accorded to professors of the Catholic, Lutheran, and Calvinistic faiths. The French Revolution marked the beginning of a new era, in which the principle of religious freedom in its widest sense has gradually secured almost universal recognition.

Literature: GIBBON, Decline and Fall of the Roman Empire; GUIZOT, Hist. of Civilization in Europe; VOLTAIRE, Essay on Toleration; LOCKE, Essays; LECKY, Hist. of Rationalism; BANCROFT, Hist. of the United States. Cf. ERASTIANISM, and GALLICANISM. (R.M.W.)

Lie [AS. leogan]: Ger. Lüge; Fr. mensonge; Ital. menzogna. Any intentional deception of another by positive misrepresentation. Cf. EQUIVOCATION.

The essence of the lie rests in the intention to deceive; yet the means of the deception, by positive misrepresentation -- as contrasted with either negative suggestion (suggestio falsi) or omission of truth (suppresio veri) -- seems, though casuistical, to be well established. The following example from Macaulay (Hist. of England, chap. ix) illustrates this 'distinction without a difference.' Bishop Compton, who had invited William of Orange to invade England in 1688, is asked by King James if there is any truth in the statement in William's manifesto that some spiritual peers had invited him; he replies: Sir, I am quite confident that there is no one of my brethren who is not as guiltless as myself in this matter.' Macaulay remarks: 'The equivocation was ingenious; but whether the difference between the sin of such an equivocation and the sin of a lie be worth any expense of ingenuity may perhaps be doubted.'

The question of the ethical justification of a lie is also quite apart; whether right or not, a lie is a lie 'for a' that.' See VERACITY, and cf. CASUISTRY. (J.M.B.- H.S.)

Life and Organic [AS. hlifian. Gr. o ganon]: Ger. Leben, Lebewesen (living being), organisch; Fr. vie, organique; Ital. vita, organico. A form of organization found in certain material things, having the properties of self-perpetuation, for a longer or shorter time, and of reproduction in some form, and further distinguished by certain characters described as vital properties or properties of LIVING MATTER (q.v.). Matter having this organization and these characters is called 'living' or 'organic,' as opposed to 'dead' or 'inorganic' matter. Cf. also PROTOPLASM.

The theories of life have always turned on the form of organization displayed, as contrasted with other forms, such as notably the chemical. The problem seems little nearer solution now than in the time of the speculations of Aristotle. To Aristotle the soul was the 'form' or 'formal cause' of the organized body, the matter of which was the 'material cause' of the living creature. The scholastic theory of 'vitality' or 'vital force' postulated a principle additional to those of mechanical action and chemical organization, a view which laboured under the obscurity of the word 'force,' and came to be directly challenged when the generalization of the CONSERVATION OF ENERGY (q.v.) was announced. This difficulty, i.e. of determining whether vital phenomena are subject to the law of conservation, has never been overcome. The question is as to whether or not vital changes, such as those of development and growth, can be adequately accounted for as transformations of the known forms of energy; and if not, what more is necessary. Current views divide into (1) the mechanical or chemical, which holds that vital phenomena are entirely explainable in terms of mechanical and chemical change; (2) vitalism or neo-vitalism, holding to a 'something over,' which takes the form (a) of a new force or energy (e.g. growth-force or bathmism of Cope; 'genetic energy' of Williams), (b) a property of 'self-adaptation' (Henslow) or 'direction' (Eimer), or (c) the assumption of a form of 'so-called' directive force which, while diverting, guiding, or shunting physical energy, yet does not alter its amount. This last view often makes consciousness the new agent, and represents a distinct tendency in discussion to restate the question in terms of a dualism between matter and mind rather than between matter and life; the additional point being assumed, or directly advocated, that life and mind are coterminous. This does not alter the essential conditions of the problem, although it is held to strengthen the position of vitalism by making accessible to it the facts and arguments in support of some sort of causal activity of mind. Philosophically, however, it has the distinct advantage of reducing two dualisms to one, and of bringing the question within the lines of one of the broadest and most critical problems, i.e. that stated by Aristotle in terms of 'matter and form,' discussed by religious philosophers under the heading of teleology, and taking the form in modern metaphysics of the inquiry as to the final category of organization (matter and motion, dualism of body and mind, or monism in some higher term). Cf. MIND AND BODY, ORGANIZATION, TELEOLOGY, and the remarks on teleology under HEREDITY. The discussion labours under the confusion hidden in the words CAUSE, FORCE, ENERGY (which should also be consulted). Cf. also ORIGIN OF LIFE.

As to the explanation of the facts involved, the rival theory to vitalism is natural selection, which is at its best in explaining the apparently vital directive movement in evolution, but weaker in explaining individual growth and development. On the other hand, vitalism makes its strongest stand in what is called the developmental mechanics of the individual, where the facts of REGENERATION (q.v.) and organic accommodation, it is held, can only be described in vitalistic terms and illustrate the inscrutable mystery of life (cf. Wilson, The Cell, 329). It is interesting to note, as illustrating the truth of this opposition, that the new vitalism is current for the most part in countries -- notably Germany and the United States -- where the problems of ontogeny are especially investigated, while in other countries -- notably England -- vitalism in any form is criticized as mysticism.

Literature: ARISTOTLE, zoological writings; WUNDT, Logik, II. i. 3, 4, 'd. Logik d. Biol.'; COPE, Primary Factors of Organic Evolution; VERWORN, Gen. Physiol. (Eng. trans.); WILLIAMS, The Genetic Energy of Organisms, Science, May 27, 1898; SANDEMAN, The Problems of Biol.; EIMER, Organic Evolution (Eng. trans.); WILSON, The Cell; OSBORN, From the Greeks to Darwin; BROOKS, Foundations of Zool., v. BUNGE, Lehrb. d. Physiol. (1889); DU BOIS-REYMOND, Ueber d. Grenzen d. Naturerkenntniss; JAPP, Pres. Add. Chem. Sec. Brit. Assoc., Report, 1898; LLOYD-MORGAN, Monist, Jan., 1899; WARD, Naturalism and Agnosticism; and most of the general works on the BIOLOGICAL SCIENCES (q.v.). (J.M.B., C.L.L.M.)

Life (spiritual) [ME. lif]: Ger. geistiges Leben; Fr. la vie spirituelle; Ital. vita spirituale. (1) That activity of a self-conscious being which gives rise to moral, aesthetic, and religious experiences.

(2) In theology: the divine life which is manifested in Christ, and in which the believer is by faith enabled to participate.

The spiritual life represents the central mystery of the Christian faith. The new birth involves the throwing away of the old carnal life and the putting on of a new life, of which the central principle is to be the spiritual energy of Jesus Christ. In the New Testament the spiritual life is not only represented as ideally rich and complete, but also as in its nature eternal as the life of God. (A.T.O.)

Light: see VISION.

Light of Nature [trans. of Lat. lumen naturae or naturale, a term used by Aquinas, Summa Theologiae, Pt. I, qu. 12, art. 13, and elsewhere. It is not necessary to suppose that he borrowed the term from the passage of Aristotle's De Anima, 430 a, 14, where the creative intellect is compared with light]: Ger. natürliches Licht; Fr. lumière naturelle (Pascal); Ital. lume naturale (Galileo). A natural power, or instinct, by which men are led to the truth about matters which concern them, in anticipation of experience or revelation. See LUMEN (also for literature).

The phrase is used in contradistinction to supernatural light. Tucker's Light of Nature pursued is a book written as a mild reaction against Locke and the Associationalists in the direction of the philosophy of common sense. (C.S.P.)

Light Sensation: Ger. Lichtempfindung; Fr. sensation lumineuse; Ital. sensazione luminosa. Visual sensation. See VISION. See also BRIGHTNESS. (E.B.T.)

Likeness or Resemblance (consciousness of) [AS. lic, in gelic, like]: Ger. Aehnlichkeit; Fr. ressemblance; Ital. somiglianza, or rassomiglianza. Two mental objects or contents are said to be alike for consciousness when in respect to certain features one might be taken for the other. This is hit off in the current conundrum: 'What is most like a rain-drop?' Answer: 'Another rain-drop.' Such objects are said to have likeness, to be alike, or to resemble each other.

Theories of likeness are based on partial identity of the two mental contents (cf. RESEMBLANCE); partial recognition of one in the other; partial assimilation of one to the other, or of both to a third; or on an active adjustment to one which holds also in part for the two. The last of these views, to which the writers adhere, is well summed up by Ward: 'Presented objects become related as "like" either in virtue of the active adjustment to a change of impression which their partial assimilation defeats, or in virtue of an anticipated continuance of the impression which this assimilation confirms' (art. Psychology, in Encyc. Brit., 9th ed., xx. 180). Cf. the classification given under RESEMBLANCE, and the topics there referred to.

The case in which two things are alike in all respects -- are taken one for the other -- is mentioned under INDISCERNIBLES, and DIFFERENCE. (J.M.B.- G.F.S.)

Limen [Lat.]: equivalent to THRESHOLD (q.v.), which is already current, and is preferred.

The adjectives 'liminal' (at the threshold), 'subliminal' (below the threshold), and 'supraliminal' (above the threshold) are useful. Cf. LIMITS OF STIMULATION. (J.M.B.)

Limitative [Lat. limitare, to enclose]: Ger. limitativ (Urtheil); Fr. limitatif; Ital. limitativo. (1) Applied to a third quality of judgments, additional to affirmative and negative. The idea of such a third quality originated among the Romans from the difference between 'homo non est bonus' and 'homo est non bonus,' the latter being the limitative.

(2) Setting limits in the sense (2) given under LIMITING NOTION (q.v.).

It is one of the numerous cases in which accidents of language have affected accepted logical forms without any good reason. Boethius and others applied the infinitation to the subject also, which De Morgan has shown makes a valuable addition to logic. Wolff, however, limited the modification to the predicate, without showing any serious reason for such application. Kant adopted it because it rounded out his triad of categories of quality. His defence, as reported by Jäsche, is that the negative excludes the subject from the sphere of the predicate, while the unendliche, limitative, or infinite judgment puts it into the infinite sphere outside the predicate. It is to be remarked that Kant regards a positive mark as differing per se from a negative one, and, in particular, as having a far narrower extension. Like most of the old logicians, he virtually limited the universe of marks to such as arrest our attention. If that had been explicitly and consistently done, it would have constituted an interesting particular logic, in which there would be a material and not merely formal difference between affirmative and negative facts. It is probable that Kant also understood the affirmative proposition to assert the existence of its subject, while the negative did not do so; so that 'Some phoenixes do not rise from their ashes' would be true, and 'All phoenixes do rise from their ashes' would be false. The limitative judgment would agree with the affirmative in this respect. This was probably his meaning, and he did not observe that his limitative judgment, 'The human soul is immortal (nichtsterblich),' may be construed as equivalent to the conjunctive judgment, 'The human soul is not mortal, and it is the human soul.' No doubt Kant would have seen a world of difference between these two assertions. In that case he should have adopted a fourth quality, 'The human soul is not immortal.' (C.S.P.)

Limiting Notion: Ger. Grenzbegriff; Fr. notion-limite; Ital. concetto limite. (1) A term used by Kant in a single passage of the Krit. d. reinen Vernunft (1st ed., 255) to signify that a NOUMENON (q.v., ad fin.), which is a thing in itself regarded as an object of reason, is something to which experience cannot attain, but is the inconceivable something behind the phenomena. The passage reads: 'Der Begriff eines Noumenon ist also bloss ein Grenzbegriff, um die Anmassung der Sinnlichkeit einzuschränken, und also nur von negativem Gebrauche.' (J.M.B.- C.S.P.)

(2) The notion of what would be the limiting or extreme case of the application of a truth or principle.

The limiting notion in this sense involves abstraction from the conditions of particular existence; and it also fulfils an ideal. Hence it is both limitative and negative with reference to existence in the sphere of the particular. Cf. LIMITATIVE (2), and LIMITS (in mathematics). The validity of Kant's negative conclusions regarding God, freedom, and immortality turns upon the construction of the negative character attributed to the limiting notion, i.e. upon the theory of reality of the noumenal or universal sort. (J.M.B.)

Limits (in mathematics) [Lat. limes, a boundary]: Ger. Grenze; Fr. limite; Ital. limite. A fixed quantity towards which we conceive or prove a variable quantity to approach, so that their difference becomes infinitesimal, though it never entirely disappears, is called a limit.

A simple example is that of the series 1/2 + 1/4 + 1/8 + 1/16 + &c., in which each term is half the preceding one. It is evident that the sum of the terms will always be less than 1 by the last term, thus 1/2 + 1/4 + 1/8 = 1 - 1/8, &c. Now since, by halving a quantity continually, we can make it less than any assignable quantity, it is clear that there is no limit to the possible smallness of the difference between the sum and 1. On the other hand, the sum can never become equal to 1, because we shall always have a difference equal to the last term of the series. In this case the value 1 is said to be the limit of the sum of the series. (S.N.)

Limits (of Stimulation (1) and (2) of Sensation): Ger. Grenzwerthe; Fr. étendue; Ital. limine. (1) The limits beyond which, in either direction, stimulation of a sense-organ is ineffective; (2) the boundaries of a sensation series or continuum. (E.B.T.)

In intensity: the extremes of intensity of stimulus that give sensations. The lower limit of sensation, the minimal sensation, the limen or THRESHOLD (q.v.), is the just noticeable intensity of sensation. The upper limit of sensation, or the maximal sensation, is that due to the most intense stimulus. The RANGE (q.v.) of sensation, according to Wundt, is measured by the maximal sensation divided by the threshold.

Wundt introduced the term Reizhöhe for the upper limit. The existence of the lower limit is in part due to the interference of physical and physiological stimuli, in part to physiological inertia and dispersion, and in part may perhaps be regarded as a case of subconscious stimulation. The upper limit is perhaps due to the injury of the sense-organ by intense stimulation. Cf. FECHNER'S LAW, WEBER'S LAW, and PSYCHOPHYSICAL METHODS. (J.McK.C.)

In quality, &c.: the term 'limits of stimulation,' with its correlate 'range of stimulation,' applies also to sensation qualities. We may determine qualitative limits in two different ways. The upper and lower limit of tone stimulation, e.g., may be given as the greatest and least number of vibrations in the second that produce a tone sensation (see Auditory Sensation under HEARING). Or we may inquire as to the least number of vibrations necessary for the cognition of a tone of given vibration rate: this number seems to vary between 2 and 20. Moreover, every sense-organ shows limits with respect to the time intervals of stimulation, while the eye and skin have also limits with respect to extent.

Literature: KÜLPE, Outlines of Psychol., 34; WUNDT, Physiol. Psychol. (4th ed.), i. 334 f. (E.B.T.)

Lindner, Otto. (1820-67.) Born and educated at Breslau, he devoted himself especially to philology and philosophy. He became a private instructor in Berlin, and in 1847 took a position on the Vossische Zeitung, becoming editor-in-chief in 1863.

Line of Beauty: Ger. Schönheitslinie; Fr. ligne de beauté; Ital. linea di bellezza. A term applied by Hogarth (1745) to a serpentine line, which he regarded as the most beautiful outline.

In his Analysis of Beauty (1753) Hogarth styled the serpentine line 'line of grace' (see GRACE), and restricted the term 'line of beauty' to the waving line (~). He regarded 'variety' as the ground of its aesthetic value. (J.H.T.)

Line of Direction: Ger. Richtungslinie (-strahl); Fr. ligne de direction; Ital. linea di direzione. The line of direction is the straight line connecting a luminous point with the nodal point of the 'reduced' eye, and prolonged to meet the retina. It gives the position on the retina of the luminous point. See Fig. 7 under VISION.

Literature: HELMHOLTZ, Physiol. Optik (2nd ed.), 91, 742; WUNDT, Physiol. Psychol. (4th ed.), ii. 98; SANFORD, Course in Exper. Psychol., expts. 106, 117; AUBERT, Physiol. Optik, 600; FICK, in Hermann's Handb. d. Physiol., III. i. 64; HERING, ibid., 349; Beitr. z. Physiol., i. (1861) 25 ff. Cf. LINE OF VISION. (E.B.T.)

Line of Regard: Ger. Blicklinie; Fr. ligne de regard (Helmholtz, Physiol. Optik, Fr. trans., 599); Ital. linea di mira. The straight line connecting the point of regard or fixation point with the centre of rotation of the eye. See Fig. 7 under VISION.

Literature: HELMHOLTZ, Physiol. Optik (2nd ed.), 91, 617, 679; SANFORD, Course in Exper. Psychol., 119, and expts. 176, 177, 219; WUNDT, Physiol. Psychol. (4th ed.), ii. 99, 121; AUBERT, Physiol. Optik, 419, 646; HERING, in Hermann's Handb. d. Physiol., III. i. 441. See LINE OF VISION. (E.B.T.)

Line of Vision or Line of Sight: Ger. Gesichtslinie; Fr. rayon visuel; Ital. linea visuale. A straight line joining the fovea with the fixation point, and making with the OPTICAL AXIS (q.v.) an angle of about five degrees. The line may also be defined in terms of the nodal point of the 'reduced' eye, and accordingly termed the 'principal ray of direction.' It is practically coincident with the LINE OF REGARD (q.v.; see also Fig. 7 under VISION).

Literature: WALLER, Human Physiol., 412; Helmholtz, Physiol. Optik (2nd ed.), 91, 617; WUNDT, Physiol. Psychol. (4th ed.), ii. 99, 121; AUBERT, Physiol. Optik, 415, 417; FICK, in Hermann's Handb. d. Physiol., III. i. 59; HERING, ibid., 349. (E.B.T.)

Linguistic Science: see PHILOLOGY, LANGUAGE, and PHONETICS.

Listing's Law: Ger. Listing'sches Gesetz der Augenbewegungen; Fr. loi de Listing pour les mouvements de l'oeil; Ital. legge di Listing.

If the LINE OF REGARD (q.v.) is carried from the primary to any other position, the torsion of the eyeball in this new position is as it would be if the eye had turned about a fixed axis, standing at right angles to both directions of the line of regard' (Helmholtz).

The law has two corollaries: (1) that in movements from the primary position there will not be, and (2) that in movements from secondary position to secondary position there will be, rotation about the line of regard. Cf. Sanford, Course in Exper. Psychol., expt. 131 b, and App. I.

Literature: HELMHOLTZ, Physiol. Optik (2nd ed.), 623; WUNDT, Physiol. Psychol. (4th ed.), ii. 116; SANFORD, Course in Exper. Psychol., expt. 131 b; AUBERT, Physiol. Optik, 646, 653; LE CONTE, Sight, 147; HERING, Binocul. Sehen (1868), 64, 68; RUETE, Lehrb. d. Ophthal., i. 37. (E.B.T.)

Littré, Maximilien Paul Emile. (1801-81.) Born and educated for medicine in Paris. In 1830 he fought on the barricades in Paris as a republican. Shortly after this he began writing scientific articles for Le National. In 1839 he became a member of the Académie des Inscriptions et Belles-Lettres. In 1840 he read the works of Auguste Comte and became a leader among the advocates of the Positive philosophy. He took up the Histoire littéraire de la France upon the death of Fauriel in 1844. In 1863 he presented the Academy with the first part of his Dictionnaire de la Langue Française; he continued also his contributions to medical literature. Member of the Assembly in 1871, and life senator after 1875. Member of the Académie Française after 1874.

Living Matter: Ger. lebendiger Stoff; Fr. substance vivante; Ital. sostanza (or materia) vivente. Matter in the peculiar unstable or labile condition which enables it to manifest the properties or functions of life. These properties are (1) nutrition in its widest sense, as including all the processes of anabolism and katabolism. (2) Reproduction: the power of changing dead (food) matter into itself, thus reproducing itself and increasing in amount up to the limit of the food supply. All known living matter has thus arisen from previous living matter. (3) Irritability, including the fundamental functions of conductivity and contractility: the property of living matter by which it is enabled to respond to stimuli, i.e. to maintain continuously internal adjustments to external changes, an essential characteristic of life. (C.F.H.)

Chemical Composition. Protoplasm is not a unitary chemical substance, but it is a complex mixture in ever-varying proportions of very many different substances. The quest for a definite chemical formula for protoplasm has proved vain. Living substance can at present be defined, not in terms of chemical composition, but in terms of its morphological and physiological properties. The nature of the bond which holds these diverse substances together and maintains the integrity and continuity of the life process during the continual flux of the elements of its physical basis, which, in short, renders living substance self-perpetuating -- this is the problem of life, and it is apparently as far from solution to-day as it was in the time of our fathers, who cloaked their ignorance under the term 'vitalism.' Cf. LIFE.

Vital manifestations, however, so far as they have yet been analysed, reduce themselves to physico-chemical forces, from which it may be inferred that the distinguishing features of living things depend upon the nature of the interrelation of these forces rather than upon any special super-physical force. But it does not at all follow that the synthesis of living substance would be possible, even if we were able to make artificially all the proximate chemical compounds which are mingled in its structure. For, as Oscar Hertwig has pointed out, none of the protoplasm now living has been formed in any other way than by the propagation of pre-existing protoplasm; it is, therefore, the product of an exceedingly long historical development.

At present, however, our knowledge of the molecular structure of the proximate ingredients of protoplasm is very meagre. The simplest of these organic compounds have very large molecules, often with more than a thousand atoms. The formula for a molecule of albumen has been given as C72 H106 N18 SO22, and for haemoglobin, C600 H960 N154 Fe1 S3 O179. This peculiarity alone is sufficient to explain many of the properties of organic substances, such as their inability in most cases to dialyze and to diffuse rapidly in solutions. For some interesting speculations growing out of the properties of the twelve elements chiefly represented in organized bodies (viz. C, N, S, H, O, P, Cl, K, Na, Mg, Ca, Fe), see Spencer's Principles of Biology and Verworn's General Physiology. The latter author gives a brief account of Pflüger's interesting researches on the rôle of cyanogen, CN, in the metabolism of proteids, from which the conclusion is drawn that the essential difference between living and dead proteid is the presence of the radical cyanogen in the former, but not in the latter. Further study of the properties of some of the non-living compounds of this radical brings out some curious resemblances with living proteid (notably in their tendency towards transformation and polymerization), and Pflüger concludes: 'Accordingly, I should say that the first proteid to arise was living matter, endowed in all its radicals with the property of vigorously attracting similar constituents, adding them chemically to its molecule, and thus growing ad infinitum. According to this idea, living proteid does not need to have a constant molecular weight; it is a huge molecule, and undergoing constant, never-ending formation and constant decomposition, and probably behaves towards the usual chemical molecules as the sun behaves towards small meteors.'

Another, and perhaps the simplest, method of considering the problem of living matter, though it suffers, as do all others, from the impossibility of concrete demonstration, concerns itself not with the analysis of the material elements of living substance into units whose quantitative formulas somehow are supposed to represent the potency of the substance, but with a synthesis of the several energies after the analogy of the composition of forces in mechanics. This theory does not suppose that the several grades of vitalized matter differ in ways that can be expressed by chemical formulas, but the forces merged into the living entity are conceived of as constituting a unitary force compounded from the more elementary ones, merged in it in such a way that, if our knowledge were complete enough, the several vital activities might be expressed somewhat as are the complex curves of geometry. The essential point of this theory lies in its insistence that the vital activity is a unit and not a compound thing. A method of dynamic notation is greatly needed in this connection.

Microscopic Structure. Casual examination of protoplasm, even with rather low magnifying powers, shows that it is by no means homogeneous; and the more thorough the examination, the more forcibly is this differentiation impressed upon the observer. When properly prepared by suitable reagents it is seen to be composed of a more fluid portion or plasma (cytolymph, enchylema, or ground-substance), and a more dense material, the spongioplasm. The latter must not, however, be regarded as normally a solid, for living substance as a whole is unquestionably liquid.

The theories of protoplasmic structure fall into two general classes: those which regard the more fluid plasma as the essential vital part, and those which regard the more dense framework as the essential, the interstitial substance serving simply as a vehicle for nutrition, &c. Though the former of these views is supported by several eminent authorities, yet the great majority of observers hold to the latter conception in some form, or regard both ingredients as equally essential. But these observers are by no means agreed as to the nature of the spongioplasm. We have, accordingly, from this point of view, four theories of protoplasmic structure: --

I. The granular theory. The miscroscope does unquestionably reveal the presence of numerous granules both in living and in prepared protoplasm, and they have given rise to much speculation. They have been variously termed micellae, pangens, ideoblasts, ideosomes, plastidules, bioplasts, gemmae, biogens, biosomes, microsomes, &c. The latter term is perhaps the most unobjectionable, as involving less of hypothetical interpretation. Many authors regard these bodies as a sort of biological unit of lower order than the cell. The existence of such units was postulated from theoretical grounds by several of the earlier authors (Spencer's 'physiological units,' Nägeli's micellae,' Darwin's 'gemmules,' &c.), and they figure very largely in the writings of several recent authors (notably Weismann and Altmann).

II. The filar theory. According to this conception, usually ascribed to Flemming, the spongioplasm is composed of interlacing threads which do not unite to form a reticulum.

III. The reticular theory. The structure is conceived of as a mass of threads which are combined into a more or less regular network. This reticular appearance is very often observed, though it is not always possible to prove that the fibres actually anastomose. The microsomes are often seen in connection with it, either at the nodes of the reticulum or strung along the fibres. Probably the majority of competent observers, at least until very recently, have held to this view.

IV. The alveolar theory. This we owe primarily to Bütschli, whose researches upon artificial foams lend some support to the belief that protoplasm is a microscopic foam or emulsion of two liquids of different densities. The fibres of the other theories are the walls of the vesicles of this emulsion as seen in optical section. This idea is being adopted, wholly or partially, by a rapidly increasing number of both zoologists and botanists, particularly those of the younger generation.

Probably no one of these conceptions expresses the whole truth. Indeed, Wilson has very recently brought forth strong direct evidence that the alveolar spheres, microsomes, and some, at least, of the true thread structures of the cytoplasm, are all different gradations of one structure. He agrees with Kölliker that 'no universal or even general formula for protoplasmic structure can be given,' and adds; 'Life in its full sense is the property of the cell-system as a whole rather than of any one of its separate elements. Nevertheless, we are perhaps justified in maintaining that the continuous substance is the most constant and active element, and that which forms the fundamental basis of the system, transforming itself into granules, drops, fibrillae, or networks in accordance with varying physiological needs.'

Properties. Since the dawn of science, there has been a strong tendency towards mysticism in the treatment of all phenomena connected with life. Of the commonly enumerated fundamental physiological properties (spontaneity, irritability, contractility, growth, reproduction, &c.), all, except possibly the last, when rigidly defined, can be shown to be manifested in some degree under proper conditions by dead substances. The specific living substance contains no elements not found in unorganized matter, though, as we have seen, these elements are probably arranged in a characteristic manner. If we follow Verworn and say that 'the life-process consists in the metabolism of proteids,' it is plain that there is no room here for any metaphysical agency, since metabolism is merely the sum of the chemical processes going on within the body.

The present tendency is to study the properties of living beings in the same way as we do the properties of other physical bodies, viz. experimentally. This, of course, has always been the method of physiology, but of late it has been widely extended into the fields of experimental morphology and experimental embryology, in the hope of determining, not only what the phenomena of these sciences are, but how they came to be so. Since all vital manifestations can probably be reduced to responses of the living material to the forces impinging upon it from the environment, this study resolves itself into two problems, viz. the intrinsic properties of the reacting substance as such, and the specific effects of outer forces upon this substance.

The former problem includes the study of the protoplasmic constants, such as general chemical properties, physical structure, heredity, &c., and is far less advanced than the latter. Since in nature these two factors are always represented in every vital phenomenon, for scientific purposes they must be artificially separated, either by logical analysis or actually, under experimental conditions. Hence the motive for the present tendency towards experimental biology. It must be admitted that this analysis has not yet been carried very far. Even HEREDITY (q.v.), the name given to the self-perpetuation of vital processes from generation to generation, is not rigidly true to type, i.e. variations occur, whose connection with external conditions cannot always be traced, and the embryologists are divided into opposing schools on the question of the relative importance to the course of the ontogeny of intrinsic, i.e. inherited, factors and those which are extrinsic, i.e. determined by the direct action of the environment. This is the modern phase of the old controversy between PREFORMATION and EPIGENESIS (see those terms, and cf. Wilson, The Cell in Development and Inheritance, particularly the last chapter).

All the phenomena of growth, however much they may be dependent upon inherent structure, are also affected variously by environmental influences. For instance, the necessity for the division of a growing body into units (cells) of small size is due simply to the fact that during growth the absorbing surface, by which alone nutriment can enter the protoplasm, increases as the square of the radius, while the protoplasmic mass, in which the consumption of nutriment takes place, increases as the cube of the radius. Obviously a limit is soon reached beyond which nutriment cannot be absorbed as fast as it is consumed, and either growth must cease or the mass must be divided so as to permit an increase of surface without a corresponding increase of mass. One of the most striking cases of the influence of external forces upon the course of development has been recently brought out by Loeb, who finds that unfertilized eggs of sea-urchins, if put into water containing a definite proportion of magnesium chloride for a short time and then transferred to ordinary sea water, will develop into normal larvae without previous fertilization. See PARTHENOGENESIS (artificial).

Again, observation shows that different organisms are adapted to very diverse environmental conditions, so that what is favourable to one may be fatal to another. This presumably rests upon a difference in the structural organization of the protoplasm. But experiment teaches us that an animal or plant may, by gradually changing the external conditions of life, be acclimated or accommodated to an environment which would have been fatal to it before. This change in the conditions of life may be brought about in a race by natural selection, or it may be produced in an individual by the direct influence of the environment upon the living matter. Davenport explains the latter case by the assumption of a specific kind of molecule in the protoplasm which is capable of responding to a certain stimulus. The repeated application of this stimulus might destroy these molecules faster than they could be replaced, and in consequence the organism would in the end be unable to respond to this particular stimulus. If the stimulus is an injurious one, the organism would no longer be injured by it. This hypothesis would explain, not only acclimatization, but also immunity after inoculations, &c.

Many attempts have been made to localize the various vital processes within the cell. Thus, the chromatin of the nucleus is regarded by many as the specific bearer of heredity. It is, however, impossible wholly to exclude the participation of the cytoplasm in the process of fertilization. The nucleus, moreover, is sometimes spoken of as the source of the chemical energy of the cell, though it is more correctly described as the centre of the metabolic activities of the cell. The nucleus is sometimes seen to migrate in a large cell to the point of most active growth, and in other cases is enlarged and curiously modified in correlation with special metabolic functions of its cell. It is well known that non-nucleated bits of protoplasm, while they may ingest and partially digest food, are incapable of assimilating it, and hence soon perish. On the other hand, experiments show that the nucleus is also incapable of prolonged life without the cytoplasm. It has also been shown that, though nucleated bits of protoplasm are in many different organisms capable of regenerating the whole body, nevertheless there is a limit of size (which differs in different animals) below which such regenerations cannot occur, on account of deficient organization, even though all the other conditions seem to be fulfilled. Thus, Lillie found that a nucleated fragment of the protozoan Stentor could regenerate the whole body, provided it contained at least one twenty-seventh of the mass of the normal Stentor, but not if smaller than this.

The reactions of organisms to external stimuli are reduced in last analysis to reactions of their individual cells; they can therefore best be studied in the unicellular animals and plants, since here each cell can express its proper reaction by free movement. Accordingly, we have an extensive series of researches upon the reactions of such cells to external stimuli, giving us the following types of simple responsive movements: (1) chemotaxis, response to chemical stimuli; (2) phototaxis (heliotropism), response to luminous stimuli; (3) thermotaxis, response to thermal stimuli; (4) hydrotaxis, movements towards or from moisture; (5) barotaxis, movements determined by pressure, and including (a) thigmotaxis (strereotaxis), movements towards or from a solid object; (b) rheotaxis, movements with reference to the direction of flow of a current of liquid; (c) geotaxis, movements with reference to the direction of gravity; (6) tonotaxis, movements with reference to the density of the medium; (7) galvanotaxis (electrotaxis), movements with reference to electrical stimuli.

It is to be noted that these simple reactions, which are common to animals and plants, include nearly all (and perhaps quite all) the elements of the simpler reflexes of higher animals. These reflexes, therefore, as Loeb has so forcibly argued, are not to be regarded as functions of nerve cells only, but rather of protoplasm as such.

The preceding reactions may all be described as 'directive effects of unilateral stimulation' (Verworn). Of course, they are not confined to unicellular organisms, for free cells within the bodies of higher animals (leucocytes, sperm cells, &c.) undoubtedly obey these laws; so also many of the movements of the bodies and organs of these animals, such as the various tropisms recognized in physiology. Even when free movement of the reacting cells is prevented by the adjacent tissues, the forces underlying chemotaxis, &c., undoubtedly govern intra-cellular life to a large extent. This is best illustrated by the selection of food. Thus, each of the various types of cells of the body, all of which are bathed in a common nutrient fluid -- the body lymph -- selects the materials of which it has need, and no others.

The ultimate explanation of all these reactions is, naturally, to be sought in internal organization. The importance of the latter factor is also shown by the fact that the same reaction often follows from very diverse stimuli. For instance, muscular contraction can be evoked by chemical, mechanical, thermal, or electrical stimulation. In other words, the organization of contractile substance is such that if its vital equilibrium is disturbed by any cause whatever, its energy is discharged in a single mode. It follows that any living tissue which has any considerable structural differentiation possesses a certain SPECIFIC ENERGY (q.v.), though just how far the 'specific energy' of any given organ (notably among the sense organs, where the term was first applied) is due to internal cellular organization of the primary reacting cells, and how far to differences in the connections of these cells with other cells, is still an open question.

Literature: Chemical composition: BUNGE, Lehrb. d. physiol. u. pathol. Chemie (3rd ed., Leipzig, 1894); GAMGEE, Physiological Chemistry of the Animal Body (London, 1880); KOSSEL, Ueber die chemische Zusammensetzung der Zelle, Arch. f. Anat. u. Physiol., Physiol. Abth. (1891); LEA, Chemical Basis of the Animal Body, Appendix to Foster's Physiol. (6th ed.); MALFATTI, Zur Chemie des Zellkerns, Ber. d. naturw. -med. Vereins zu Innsbruck, xx (1891-2); NEUMEISTER, Lehrb. d. physiol. Chemie (2nd ed., Jena, 1897); PFLÜGER, Ueber die physiologische Verbrennung in den lebendigen Organismen, Arch. f. d. ges. Physiol., x (1875); REINKE and RODEWALD, Stud. ü. das Protoplasma (Berlin, 1881); SCHWARZ, Die morphologische und chemische Zusammensetzung des Protoplasmas, Beitr. z. Biol. d. Pflanzen, v (Breslau, 1887); ZINOFFSKY, Ueber die Grösse des Hämoglobinmolecüls, Zeitsch. f. physiol. Chemie, x (1885); LOEW, Die chemische Energie der lebenden Zellen (Munich, 1899); The Proteids of Living Matter, Science, N.S., xi (1900).

Microscopic structure: R. ALTMANN, Die Elementarorganismen u. ihre Beziehungen zu den Zellen (2nd ed., Leipzig, 1894); G. F. ANDREWS, The Living Substance as such and as Organism, J. of Morphol., xii. No. 2, suppl. (1897); TH. BOVERI, Zellenstudien, Jena. Zeitsch. f. Naturwiss., N. F., xiv (1887), xv (1888), xvii (1890); O. BÜTSCHLI, Untersuch. ü. mikr. Schäume u. das Protoplasma (Leipzig, 1892; Eng. trans. with extensive bibliog., London, 1894); J. B. CARNOY, A series of articles in La Cellule, i. ff.; Y. DELAGE, La Structure du Protoplasma et les Théories sur l'Hérédité (Paris, 1895); T. W. ENGELMANN, Zur Anatomie und Physiologie der Flimmerzellen, Arch. f. d. ges. Physiol., xxiii (1880); R. v. ERLANGER, Neuere Ansichten über die Struktur des Protoplasmas, Zool. Centralbl., iii (1896); W. FLEMMING, Zellsubstanz, Kern u. Zelltheilung (Leipzig, 1882); Neue Beiträge zur Kenntniss der Zelle, ii. Theil, Arch. f. mikr. Anat., xxxvii (1891); M. HEIDENHAIN, Ueber Kern und Protoplasma, Festschr. f. Kölliker (1893); L. F. HENNEGUY, Leçons sur la Cellule (Paris, 1896); O. HERTWIG, Die Zelle und die Gewebe (Jena, 1892; Eng. trans., The Cell, Outlines of General Anat. and Physiol., London and New York, 1895); C. NÄGELI, Mechanisch-physiol. Theorie der Abstammungslehre (Munich and Leipzig, 1884); E. A. SCHÄFER, On the Structure of Amoeb. Protoplasm, Proc. Roy. Soc. (London, 1891); E. STRASBURGER, Zellbildung und Zellteilung (3rd ed., Jena, 1880); Stud. ü. das Protoplasma, Jena. Zeitsch. f. Naturwiss., x (1876); W. WALDEYER, Die neueren Ansichten über den Bau und das Wesen der Zelle, Deutsch. med. Wochensch. (1895); A. WEISMANN, Essays upon Heredity and kindred Biol. Problems (trans. from the German; 2 vols., Oxford, 1892); The Germ-Plasm, a Theory of Heredity (trans., New York, 1893); J. WIESNER, Die Elementarstruktur u. das Wachstum d. lebenden Substanz (Vienna, 1892); E. B. WILSON, The Cell in Devel. and Inheritance (New York and London, 1898); The Structure of Protoplasm, in Biol. Lects. delivered at the Marine Biol. Lab. 1898-9 (Boston, 1899), also in Science, N.S., x, July 14, 1899; A. ZIMMERMANN, Die Morphologie und Physiologie des pflanzlichen Zellkernes, eine krit. Litteraturstudie (Jena, 1896).

Properties: BERTHELOT, Fixation directe de l'Azote atmosphérique libre par certains Terrains argileux, C. R. Acad. d. Sci., ci (1885), cxv (1892), cxvi (1893); A. BINET, The Psychic Life of Micro-organisms (authorized trans., Chicago, 1890); G. BORN, Ueber Verwachsungsversuche mit Amphibienlarven, Arch. f. Entwicklungsmech., iv (1896); H. BUCHNER, Die chemische Reizbarkeit der Leukocyten, &c., Sitzber d. Ges. f. Morphol. u. Physiol. z. München, vi (1891); C. B. DAVENPORT, A Preliminary Catalogue of the Processes concerned in Ontogeny, Bull. Mus. Compar. Zool., xxvii. 6 (1895); Exper. Morphol., Pt. I (New York and London, 1897), Pt. II (1899; contains extensive classified bibliographies); DAVENPORT and CASTLE, On the Acclimatization of Organisms to High Temperatures, Arch. f. Entwicklungsmech., ii. 2 (1895); DAVENPORT and NEAL, On the Acclimatization of Organisms to Poisonous Chemical Substances, Arch. f. Entwicklungsmech., ii. 4 (1896); R. DUBOIS, Sur la Perception des Radiations lumineuses par le Peau, chez les Protées aveugles des Grottes de la Carniole, C. R. Acad. d. Sci., cx (1890); H. DRIESCH, Heliotropismus bei Hydroïdenpolypen, Zool. Jahrb., System. Abth., v (1890); Entwicklungsmech. Stud., i-vi, Zeitsch. f. wiss. Zool. (1891-3); Analytische Theorie d. organischen Entwicklung (Leipzig, 1894); Stud. ü. das Regulationsvermögen d. Organismen, Arch. f. Entwicklungsmech., v (1897); TH. EIMER, Die Entstehung der Arten auf Grund von Vererben erworb. Eigenschaften (Jena, 1888; Eng. trans., London, 1890); T. W. ENGELMANN, Über Licht-und Farbenperception niederster Organismen, Arch. f. d. ges. Physiol., xxix (1882); Bacterium photometricum, ein Beitrag zur vergleichenden Physiologie des Licht- und Farbensinns, Arch. f. d. ges. Physiol., xxx (1883); Ueber Bewegungen der Zapfen und Pigmentzellen der Netzhaut, &c., Arch. f. d. ges. Physiol., xxxv (1885); R. v. 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HIS, Unsere Körperform und das physiologische Problem ihrer Entstehung (Leipzig, 1874); Ueber mechanische Grundvorgänge thierischer Formenbildung, Arch. f. Anat. u. Physiol., Anat. Abth. (1894); H. S. JENNINGS, The Psychology of a Protozoon, Amer. J. of Psychol., x. 4 (1899); The Behaviour of Unicellular Organisms, Woods Holl Biol. Lects. for 1899 (Boston); Studies on Reactions to Stimuli in Unicellular Organisms -- I. Reactions to Chemical, Osmotic, and Mechanical Stimuli in the Ciliate Infusoria, J. of Physiol., xxi (1897); II. The Mechanism of the Motor Reactions of Paramecium, Amer. J. of Physiol., ii (1899); III. Reactions to Localized Stimuli in Spirostomum and Stentor, Amer. Natural., xxxiii (1899); IV. Laws of Chemotaxis in Paramecium, Amer. J. of Physiol., ii (1899); V. On the Movements and Motor Reflexes of the Flagellata and Ciliata, Amer. J. of Physiol., iii (1900); -- Reactions of Infusoria to Chemicals, a Criticism, Amer. Natural., xxxiv (1900); P. JENSEN, Ueber den Geotropismus niederer Organismen, Arch. f. d. ges. Physiol., liii (1893); E. KORSCHELT, Beiträge zur Morphologie und Physiologie des Zellkerns, Zool. Jahrb., Abth. f. Anat., iv (1889); F. E. LILLIE, On the Smallest Parts of Stentor capable of Regeneration, a Contribution on the Limits of Divisibility of Living Matter, J. of Morphol., xii. I (1896); J. LOEB, Einleitung in die vergleichende Gehirnphysiologie und vergleichende Psychologie, &c. (Leipzig, 1899; Eng. trans., 1900); On the Artificial Production of Normal Larvae (Arbacia), Amer. J. of Physiol., iii. 9 (1900), and Science, N. S., xi. No. 277 (1900); O. LOEW, Ein natürliches System der Gift-Wirkungen (Munich, 1893); The Energy of the Living Substance (London, 1896); E. MACH, Beiträge zur Analyse der Empfindungen (Jena, 1886); Die Principien der Wärmelehre (Leipzig, 1896); J. MASSART, La Sensibilité à Concentration chez les Êtres unicellulaires marins, Bull. Acad. Roy. Belg. (3) xxii (1891); Sur l'Irritabilité des Noctiluques, Bull. Sci. France et Belg., xxv (1893); E. MAUPAS, Sur la Puissance de Multiplication des Infusoires ciliés, C. R. Acad. d. Sci., civ (1887); E. METSCHNIKOFF, Leçons sur la Pathologie comparée de l'Inflammation (Paris, 1892); C.S. MINOT, Senescence and Rejuvenation, J. of Physiol., xii (1891); T. H. MORGAN, Experimental Studies on Echinoderm Eggs, Anat. Anz., ix. 5, 6 (1893); Studies of the 'Partial' Larvae of Sphaerechinus, Arch. f. Entwicklungsmech., ii. I (1895); Half Embryos and Whole Embryos from one of the first two Blastomeres of the Frog's Egg, Anat. Anz., x. 19 (1895); The Fertilization of Non-nucleated Fragments of Echinoderm Eggs, Arch. f. Entwicklungsmech., ii. 2 (1895); The Production of Artificial Astrospheres, Arch. f. Entwicklungsmech., iii (1896); W. A. NAGEL, Ueber Galvanotaxis, Arch. f. d. ges. Physiol., lix (1895); Der Lichtsinn augenloser Thiere (Jena, 1896); W. PFEFFER, Ueber chemotakt. Bewegungen, Untersuch. Bot. Inst. Tübingen, ii (1888); JULIA B. PLATT, On the Specific Gravity of Spirostomum Paramecium, and the Tadpole, Amer. Natural., xxxiii (1899); H. QUINCKE, Ueber den Einfluss des Lichtes auf den Thierkörper Arch. f. d. ges. Physiol., 1vii (1894); A. RAUBER, Ueber den Einfluss der Temperatur, Sitzber. d. Naturf.-Ges. z. Leipzig, x (1884); W. ROUX, Gesammelte Abhandl. ü. Entwicklungsmech. d. Organismen (Leipzig, 1895); H. S. RUSSELL, The Effects of Mechanical Movement, Bot. Gaz., xvii (1892); J. SACHS, Gesammelte Abhandl. ü. Pflanzenphysiol. (Leipzig, 1892); A. SCHAPER, Experimental Studies, J. Boston Soc. Med. Sci. (Jan., 1898); Arch. f. Entwicklungsmech., vi (1898); O. v. SICHERER, Chemotaxis der Warmblüter-Leukocyten ausserhalb des Körpers, Münch. med. Wochensch., xliii (1896); E. STRASBURGER, Wirkung des Lichtes und der Wärme auf Schwärmsporen, Jena. Zeitsch. f. Naturwiss., xii (1878); H. M. VERNON, The Effect of Environment on the Development of Echinoderm Larvae, an Experimental Inquiry into the Causes of Variation, Philos. Trans. Roy. Soc., clxxxvi. B (1895); M. VERWORN, Psychophysiologische Protistenstudien (Jena, 1889); Allg. Physiol. (Jena, 1897); General Physiology, an Outline of the Science of Life (Eng. trans., London and New York, 1899; contains a good bibliography); A. D. WALLER, Galvanotropism of Tadpoles, Sci. Progress, iv (1895); S. WATASÉ, On the Nature of Cell-Organization, Woods Holl Biol. Lects., 1893 (Boston); C. O. WHITMAN, The Seat of Formative and Regenerative Energy, J. of Morphol., ii (1888); The Inadequacy of the Cell-theory of Development, Woods Holl Biol. Lects., 1893 (Boston); Evolution and Epigenesis, Woods Holl Biol. Lects., 1894 (Boston); S. R. WILLIAMS, The Specific Gravity of some Fresh-water Animals in relation to their Habits, Development, and Composition, Amer. Natural., xxxiv (1900); S. WINOGRADSKY, Recherches sur les Organismes de la Nitrification, Ann. d. l'Inst. Pasteur, iv (1890); Recherches sur l'Assimilation, Arch. des Sci. Biol. de St.-Petersbourg, iii (1895); R. M. YERKES, Reaction of Entomostraca to Stimulation by Light, Amer. J. of Physiol., iii. 4 (1899); E. YUNG, Contributions à l'Histoire de l'Influence des Milieux physiques sur les Êtres vivants, Arch. de Zool., vii (1878), and 2nd series, i (1883); De l'Influence des Lumières colorées sur le Développement des Animaux, Mitteil. d. zool. Stat. zu Neapel, ii (1880), and C. R. Acad. d. Sci., cxv (1892); L. ZENDER, Die Entstehung des Lebens aus mechanischen Grundlagen entwickelt, Pts. I and II (Tübingen, 1900); O. HERTWIG, Zeit- und Streitfragen der Biologie (Jena, i. 1894, ii. 1897); E. B. WILSON, Recent Aspects of Biological Research; Origin of Life and Heredity, Int. Monthly, ii. (1900). (H.H.)

Local Sign: Ger. Lokalzeichen; Fr. signes locaux; Ital. segni locali. A specific 'shading' or 'colouring' of certain sensations whereby every such sensation is invariably referred to a definite position upon the organ or elsewhere in space.

The local signs of pressure may be regarded either as intensive differences of thickness in the epidermis, differences in tightness of the stretching of the skin over underlying parts, &c. (Lotze), or as qualitative (Wundt). The local signs of vision may be simple sensations set up by reflex movements of ocular rotation (Lotze, Helmholtz), similarity and difference of neighbouring and remote impressions (Lipps), or complexes of 'movement' sensations and retinal qualities (see INDIRECT VISION), such as gradations in colour tone (Wundt, Baldwin). Some sort of local sign is a necessity for theories of space-perception of the class designated genetic nativism in the article EXTENSION (q.v.). In some cases localization can be shown, by experiment, to imply the existence of a disparate local sign: so tactual localization by association with vision. This fact is, so far, an argument for the existence, in other cases, of a local sign in kind. See SPACE (perception of), and EXTENSION. (E.B.T.)

This sort of localization should be distinguished from the perception of space or of extension. See SPACIALIZATION. Specific LOCALIZATION IN SPACE (q.v., I) may require a local sign independently of or in addition to the data of the perception of extension, as appears negatively in the vague LOCALIZATION OF SOUNDS (q.v., also LOCALIZATION IN SPACE, 2). (J.M.B.)

Literature: LOTZE, Med. Psychol. (1852); STUMPF, Ursprung d. Raumvorstellung, 86 ff.; Zeitsch. f. Psychol., iv. 70 ff.; KÜLPE, Outlines of Psychol., 344, 368 ff.; SANFORD, Course in Exper. Psychol., expt. 1; HELMHOLTZ, Physiol. Optik (2nd ed.), 670, 947; WUNDT, Physiol. Psychol. (4th ed.), ii. 36 ff., 231 ff.; Human and Animal Psychol., 168 f.; Outlines of Psychol., 105, 127, 134 ff.; LIPPS, Psychol. Stud. (1885), i; Grundthatsachen d. Seelenlebens, 476 f., 488 ff., 513 ff., 542 ff.; FUNKE, in Hermann's Handb. d. Physiol., III. ii. 404 ff. See also under EXTENSION. (E.B.T.)

Localization (cerebral) [Lat. locus, place]: Ger. corticale Localisation; Fr. localisations cérébrales (generally plural); Ital. localizzazioni funzionali del cervello. (1) The doctrine that various parts of the brain have relatively distinct functions.

(2) The theory that certain psychical and physiological functions are limited to definite areas or regions of the brain (especially the distribution of conscious activities, such as visual, auditory, and other sensations, as well as voluntary movement of various groups of muscles, to sharply limited areas of cortex).

The theory in its broadest form is thoroughly substantiated by anatomical, pathological, and experimental data.

Two distinct tendencies are represented by the schools headed by Ferrier and Munk on the one hand, and Goltz on the other; the one school claiming that well-defined areas may be recognized, whose functions are limited to reactions upon a single set of muscles or a single class of sensory disturbances, or both; the other laying great emphasis on the unity of the brain, and the fact that injury to any region affects the whole cortex, altering the psychical tone as a whole. Munk claims that such motor disturbances as occur after injury, e.g. to the parietal cortex, depend upon an impairment of the sensations necessary to the release of such movements.

Probably the two views are not necessarily antagonistic when properly interpreted. It may be granted that certain areas of cortex actually stand primarily related to certain groups of muscles (or their myelonic centres), and certain other areas receive the stimuli elaborated in the primary projection centre for one organ of special sense; but it may still be true that every mental presentation is a result of a process of equilibration in the entire organ, and thus that a localized injury will express itself in alterations of mental tone rather than a simple abolition of a single kind of mental expression or a specific modification of consciousness.

The undoubted fact of substitutional functioning is not difficult to understand in view of the great complexity of the cortex, and especially of the far-reaching inter-communication of its different regions.

The precise and minute delimitation of the motor and sensory areas is of great practical importance as an aid in diagnosis and operation in intra-cranial injuries; but it has much less significance for the proper construction of metal processes than has sometimes been supposed.

Our most reliable data are derived from experimental study of lower animals and records of autopsies in cases of brain trauma. Naturally the results of complete extirpation of the hemispheres have not been observed in man. In a few instances such an operation has succeeded in dogs, with results such as the following: strong irritation of the skin caused the animal to growl and bite, loud noises awakened him from sleep, taste of food excited impulse to eat, and he reacted to some extent to visual stimuli. On the other hand, originative power was destroyed and all trace of recognition and memory was obliterated. In other words, although complicated cyclical reflexes exist, there is no evidence of psychic functions of the higher orders. All voluntary motion is, of course, impossible.

The researches of Munk have proved the very minute delimitation of the motor areas for the limbs and body regions, and also for the special senses. The centrifugal paths from the various parts of the cortical field for vision are said to be arranged to correspond quite minutely with the parts representing the various parts of the retina, so that visual stimuli give rise to co-ordinated oculo-motor reflexes appropriate to direct the axes of vision towards the segment of the retina stimulated, and experimental irritation of these cortical regions calls out the same reflexes -- the subject not being under the influence of an anaesthetic.

Removal of a single cortical motor centre, or the cortical centres for both limbs on one side, results in the permanent prevention of all independent voluntary motions of the corresponding muscles, but such motions as are performed in common with other organs, especially those of the corresponding muscles of the other side, may still be performed. So walking, swimming, and co-ordinated motions may coexist with a true cortical hemiplegia, thus showing that the volitional stimulus for correlated motions passes via a secondary apparatus below the cortex. The arrangement explains the possibility of an acquired quasi-reflex mechanism. The areas for general sensation correspond in general to the cortical motor areas for the same regions, though the two are not mutually inclusive. The reported loss of sensation due to operative injury of the hippocampal region and limbic lobe is probably due to simultaneous injury of corona fibres which here lie near the surface.

While removal of the cortical areas for the extremities destroys permanently the tactile sensations for the corresponding members, the general sensitiveness remains, as also the response to painful irritation. The localized tactile sense is abolished, while general sensation and pain are simply modified or diminished.

The explanation of the facts of localization is attended with difficulties, but it is rendered simpler by recent histological researches (see BRAIN, and NERVOUS SYSTEM). Munk refers the loss of motor and sensory power resulting from extirpation of the cortical areas to the prevention of the formation of the motor and sensory presentations. A dog whose visual sphere is removed may then be said to suffer psychical blindness, and it would be but a step to add that the motor inco-or-dination resulting from injuries to the centres for the extremities is a psychical paralysis (cf. PSYCHIC DUMBNESS). The minute delimitation of the areas for each segment of a sensory field is rendered impossible by the overlapping and intercommunication between them, but there is no reason to doubt the existence of such extensive representation on the cortex. The most recent experiments all confirm the idea that the entire cortical representative apparatus reacts as a single mechanism, so that every 'state of consciousness' is in a sense the product of the equilibration of the totality of cortical activities. The preponderance of activity in one sensory sphere affects this rapport, in a way constituting a conscious excitation of that sense. It follows that any injury to one part of that cortex not only abolishes the vestiges of previous excitations of that sense, but enfeebles the entire intelligence, by cutting out a variety of associational vestiges, both of the lost sense excitations and of presentations in which they formed an essential part, though originating in other spheres.

Details of localization may be gathered from the figures.

Historical. That the brain is in some way associated with thought was recognized very early, and this view prevailed among the Greek physicians, in spite of the fact that Aristotle described the brain as the most bloodless and inert organ of the body, designed simply to regulate the heat of the latter, much as the condensing vapours of the sky mitigate summer heat and drought. Pythagoras, Hippocrates, and Plato clearly recognized the head as the seat of the intellect and will, while in the days of Ptolemy Soter some attempt was made to localize functions. Erasistratus believed that the sensory nerves spring from the meninges, while the motor are derived from the substance of the brain itself (a view intelligible when we take into account the close attachment of the sensory ganglia to the meninges). Hierophilus is said to have anticipated Descartes in the belief that the vital forces reside in the ventricles, a view to which the followers of Galen also subscribed. The Arabian physicians and their successors extended the doctrine of localization. Albertus Magnus assigned judgment to the frontal regions, imagination to the parietal, and memory to the occipital. The notion of animal spirits within the ventricles survived to some extent till the 18th century. Malpighi was the first to ascribe the higher functions to the grey matter.

Descartes was the first to elaborate a consistent theory of brain functioning. Influenced by Harvey's discovery of the mechanics of circulation, he taught that the friction involved in circulation sufficed to vaporize and excite various elements of the blood. Some of these elements pass to the reproductive organs, and behave as the forerunners of Darwin's gemmules might be expected to do, while others, destined to the brain, there evolve the gaseous animal spirits on which nervous action depends. All nerves are tubes containing these spirits. In the sensory nerves the currents set towards the brain, where the agitation is communicated to the central mass of vital fluids therein. The currents thus produced may, under suitable conditions, pass out through the motor nerves to muscles, producing what are now called reflexes. The soul itself is lodged in the 'pineal body,' which was selected from among the organs of the body because of its central azygous position and its close connection with the ventricles. The soul is usually affected by the currents setting from the body, and fabricates its presentations from the impression thus derived, but it also impresses its own acts upon the vital fluids, giving rise to motor currents. Aimless eddies may produce phantasy, and there is a separate mental activity to correspond to each form of disturbance in the vital humours.

Descartes' speculations prepared the way for a variety of localization theories. Willis located memory in the convolutions, imagination in the callosum, sense-perception in the striatum, visual perception in the thalamus, and involuntary motion in the cerebellum. Meyer, on the other hand, regarded the cerebellum as the organ of abstraction, and located memory in the roots of the cranial nerves. Thus the way was prepared for Gall and Spurzheim. Gall's theory rested on the assumption that the skull depends for its form upon the growing brain, that therefore its surface reflects the state of development of the brain, and that size and configuration alone determine mental power. To these may be added sundry crude psychological postulates. Though phrenology is primarily a system of psychology, its popularity depended on the purely empirical form in which it was clothed, while what really gave it its power with the masses was the fact that it served to give a scientific character to certain theories which survived astrology under the name of physiognomy or cheiromancy.

The researches of Broca, by which he was enabled, in 1861, to locate a cortical centre for articulate speech, mark the real beginning of the modern doctrine of cortical localization. For a time all disturbances of speech were referred to this area. Our present knowledge permits us to state that lesions of the posterior portion, or pars opercularis, of the third frontal gyrus (commonly known as Broca's convolution, marked 'speech' on Fig. 3) produce motor aphasia, called 'Broca's type,' but many hold that it is amnesic aphasia, the pure motor aphasia arising from a subcortical lesion. The accidental discovery by Fritsch and Hitzig, during the Franco-Prussian War, that the galvanic current applied to the cortex is capable of exciting the motor mechanism, opened the way for experimental researches, and from this time onward the pathological method and the experimental have co-operated in the cultivation of this field. For details of localization in the case of speech, see SPEECH AND ITS DEFECTS.

Literature: besides the general treatment in the various physiological psychologies, the following special memoirs may be consulted: BEEVOR and HORSLEY, A Minute Analysis of Cortical Centres in the Monkey, Philos. Trans. Roy. Soc. (1887, 1888); also Arrangement of the Excitable Fibres of the Internal Capsule of the Bonnet Monkey, Philos. Trans. Roy. Soc. (1890, B); BROCA, Sur le Siège de la Faculté du Langage articulé, &c. ) Paris, 1861); J. M. CHARCOT and A. PITRES, Les Centres moteurs corticaux chez l'Homme (Paris, 1895); H. H. DONALDSON, Report of Six Lectures on Cerebral Localization, Amer. J. of Psychol. iv (1891); L. F. BARKER, The Sense-areas and Association-centres in the Brain, as described by Flechsig, J. of Nerv. and Ment. Dis., xxiv (June 6, 1897); L. EDINGER, The Significance of the Cortex considered in connection with a Report upon a Dog from which the whole Cerebrum had been removed by Professor Goltz, J. of Compar. Neurol., iii (June, 1893); EXNER, Untersuch. ü die Localisation d. Functionen in d. Grosshirnrinde des Menschen (1884); FERRIER, The Functions of the Brain (1876); FLOURENS, Recherches expérimentales sur les Propriétés et les Fonctions du Syst. nerv. (1824); FRITSCH and HITZIG, Ueber die electrische Erregbarkeit des Grosshirns (1870); GOLTZ, in Pflüger's Arch. (1876-84), various articles; HERRICK, Neurology and Psychology, J. of Compar. Neurol., i (1891); HORSLEY and SCHÄFER, A Review of Experiments upon the Functions of the Cerebral Cortex, Philos. Trans. Roy. Soc. (1888); LONGET, Anat. et Physiol. du Syst. nerv. (1842); LUCIANI and SEPPILLI, Die Functions-Localisation auf der Grosshirnrinde (Leipzig, 1886), trans. of the original, issued as a prize paper by the R. Ist. Lombardo di Scienze e Lettere (1885); LUCIANI and TAMBURINI, Sulle Funzioni del Cervello, Centri psicomotorii e Centri psicosensorii, Riv. Sperim. di Freniat. (1878-9); LUCIANI, Sulle Funzioni del Cervelletto, Riv. Freniat. (1879); and II Cervelletto, Pubblicaz. del R. Istituto sup. (Firenze, 1891); MAGENDIE, Leçons sur la Fonction du Syst. nerv. (1884); C. K. MILLS, Cortial Localization in the Light of Recent Researches into the Minute Anatomy of the Cortex, J. of Nerv. and Ment. Dis., N.S., xx (1895); also Cerebral Localization in the Light of Recent Pathological Researches, J. of Amer. Med. Assoc., xxvi (1896), and The Nerv. Syst. and its Diseases (Philadelphia, 1898); MUNK, Ueber die Functionen der Grosshirnrinde, Gesammelte Mittheilungen (2nd ed., Berlin, 1890); Ueber die Fühlsphären der Grosshirnrinde, Sitzber. kgl. preuss. Akad. zu Berlin (1892 ff.); Ueber den Hund ohne Grosshirn, Arch. f. Anat. u. Physiol., Physiol. Abth. (1894); NOTHNAGEL and NAUNYN, Ueber die Localisation d. Gehirnkrankheiten (1887); J. SOURG, Le Syst. nerv. central (1899); A. TAMBURINI, Contrib. alla Fisiol. e Patol. del Linguaggio, Riv. Freniat. (1875); VULPIAN, Leçons de Physiol. du Syst. nerv. (1866). (H.H.)

Localization (in space). Localization in space is the reference of a sense impression or of an object to a local position.

The two general questions which should be distinguished are those (1) of the distribution of localities on the area of the skin and retina (see LOCAL SIGN), together with the nervous PROJECTION (q.v.) of sensations as such to the surface of the body; and (2) the locating of objects in the external world. See SPACIALIZATION.

The earliest theory of space localization in the sense of (1) is what Hamilton calls 'the common dogma of the schools, that the soul is all in the whole body, and all in every one of its parts' (Reid's Works, Suppl. Diss., 861, note). Then follows the doctrine of Descartes, that the soul immediately perceives the images in the corporeal phantasy, viz. the brain. The modern treatment of the subject may be said to start with Herbart in Germany and with Bain in England.

Literature: for the Herbartian view see VOLKMANN, Lehrb. d. Psychol., ii. 117-26; and for Bain's view see BAIN, The Senses and the Intellect, 415 ff. Cf. the textbooks of psychology. See also EXTENSION, and SPACE (perception of). (G.F.S.- J.M.B.)

Localization (in time). The reference by the subject of an event in his own history to its position in the time series relatively to the present moment and to other events, past and future. See TIME.

The question of the conditions of time localization is comparatively modern. Its detailed treatment begins with the Herbartian psychology in Germany. For something of the theory see TEMPORAL SIGN.

Literature: VOLKMANN, Lehrb. d. Psychol., ii. 11-20. There is little written on the subject by the classical English psychologists; see, however, JAMES MILL, Analysis, chap. x. The best modern reference in English is, perhaps, WARD, art. Psychology, Encyc. Brit., 64-5. See the textbooks of psychology. (G.F.S.- J.M.B.)

Localization of Sounds: Ger. Lokalisation der Gehörsempfindungen; Fr. localisation des sensations auditives; Ital. localizzazione (or projezione) spaziale delle sensazioni uditive. The reference of sounds to particular localities in space. See SPACIALIZATION. (J.M.B.)

Our apprehension of the distance and direction of sounds appears to be conditioned, primarily, by the relative intensity of the waves that reach the two ears. Localization of sounds is thus a function of BINAURAL HEARING (q.v.). It is doubtful how far the pure auditory perception could have developed without visual perception; and, indeed, no explanation has as yet been proposed that is adequate in detail to the observed phenomena.

Literature: PREYER, Pflüger's Arch., xl; VON KRIES, Zeitsch. f. Psychol., i. 235, 488; MÜNSTERBERG, Beitr. z. exper. Psychol., ii, and (with PIERCE) Psychol. Rev., i. 461; RAYLEIGH, Nature, xiv. 32; SANFORD, Course in Exper. Psychol., expts. 101-3; MATSUMOTO, Yale Studies, v. 1 ff.; SCRIPTURE, ibid., 76 ff.; ANGELL and FITE, Psychol. Rev., viii. 225. (E.B.T.)

Localized Industry: Ger. Weltwirthschaft, localisirte Industrie; Fr. spécialisation (d'industrie) locale; Ital. industria locale specializzata. The division of labour between different communities.

'We may mark off three stages of industrial development. The first is where the distinction of trades is introduced, and men no longer consume all or perhaps any part of the articles they have produced; yet where consumers live near the producer and are personally known to him. The second stage is where the element of personal acquaintance disappears. Production no longer waits for orders, but anticipates demand. The third stage is reached when increasing facilities of communication make the world one trading community. Then the localization of trades proceeds so far that one country, or perhaps one group of towns, produces the greater part of all the goods of a certain sort that are consumed throughout the world' (Walker). (A.T.H.)

Locke, John. (1632-1704.) Born at Wrington, Somersetshire, England, he was educated at Westminster School, London, and Christ Church, Oxford. Secretary to Sir Walter Vane at Berlin, &c., 1665-6; formed the acquaintance of Ashley, afterwards Earl of Shaftesbury, 1666. He entered Lord Ashley's family, directing the education of his son and grandson. As lord chancellor, Shaftesbury made him 'secretary of presentations' to benefices. He stayed in France and Italy, 1675-9, and in Holland, 1684-9. In 1690 he published his famous 'Essay,' and died at Oates in Essex, Oct. 28, 1704. He is founder of English EMPIRICISM (q.v., also SENSATIONALISM).

Locomotion (1) and (2) Locomotor [Lat. locus, place, + motio, a moving]: Ger. (1) Locomotion, (2) Bewegungs- (werkzeug, &c.); Fr. locomotion, locomoteur; Ital. (1) locomozione, (2) locomotore. (1) The act or power of moving from place to place. (2) Pertaining to the mechanism of locomotion. See MOVEMENT, and MUSCLE. (C.F.H.)