Classics in the History of Psychology

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Definitions Do - Dz

Posted June 2000

Docetism [Gr. dokein, to imagine, appear]: Ger. Doketismus; Fr. docétisme; Ital. Docetismo. The doctrine of the Docetae -- that during his earthly life Christ possessed a phenomenal or phantom body, not a real or natural one.

This 'heresy' was an early result of the many difficulties connected with the problem of two natures in a single personality. Christian apologists, like Clemens Alexandrinus, regarded the Docetae as a regularly constituted sect, founded by Julius Cassianus. The truth rather is that Docetism was an inevitable accompaniment of the peculiar speculations of the Manichaeans and Gnostics, the former taking a more extreme view than the latter, and extending their phenomenalism, not only to Christ's body, but practically to all occurrences connected with his life as a man (the crucifixion, resurrection, &c.). Some of the later mystics, like Boehme, have displayed Docetic leanings. Cf. GNOSTICISM, and MANICHAEISM. (R.M.W.)

Documentary Hypothesis: Ger. Urevangeliumshypothese; Fr. hypothèse de l'évangile primitif; Ital. ipotesi documentaria. A hypothesis regarding the composition of the books of the Bible out of which the HIGHER CRITICISM (q.v.) may be said to have sprung. It consisted essentially in the theory that discrepancies were to be reconciled by the recognition of a plurality of documents, and of an editor who used these documents. It was originated by Du Pin and Witsius, at the end of the 17th century, and reached its zenith with Eichhorn and his school in the last quarter of the 18th century.

Literature: DU PIN, A New Hist. of Eccles. Writers (Eng. trans.), I f.; WITSIUS, Misc. Sacra, 103 f.; LOWTH, Preliminary Diss. and Trans. of the Prophecies of Isaiah; EICHHORN, Einleit. ins Alt. Test.; and Urgeschichte (in Repertorium f. Biblische u. Morgenländische Litt.), iv, and espec. v. 187 f. (R.M.W.)

Dogma [Gr. dogma, a thing thought]: Ger. Dogma; Fr. dogme; Ital. dogma. (1) Any expression or embodiment of an opinion or belief; a teaching or doctrine explicitly stated. This is the primary sense of the term, and is relatively neutral as compared with other usages.

(2) A formula authorized by the official representatives, or by the finally decisive expounders, of the faith of the Christian Church, or of any branch of that church whose teaching may be in question, such formula being expressive of what this religious body not only holds to be the truth, but officially requires its followers to accept. In a similar sense, the term dogma may be used to name the explicit or official teaching of any religious body whatever, whether Christian or not, although historical usage connects the word dogma most frequently with the Christian Church, as represented by the decisions and formulations of the General Councils, or of the popes, respecting the faith, and also, especially in more modern discussion, with the various formulated creeds of the bodies into which Christendom has come to be divided.

(3) An expression of a more or less fundamental and universal conviction, without any statement of the grounds for such conviction, or with an explicit refusal to attempt to give such grounds, or with an insufficient or uncritical statement of these reasons.

In this sense the term is often used as a term of reproach, and in polemic philosophical writing frequently implies that the teaching called a dogma is held by the opponent upon insufficient grounds. In this sense one speaks of a 'mere dogma.' In this sense too Kant regards earlier philosophy, and especially the Leibnitz-Wolffian philosophy, as dogmatism, and so calls it because of his failure to meet his own critical requirements. In order, however, to give this polemic sense of the term dogma a more precise formulation, Kant himself (Krit. d. reinen Vernunft, 2nd ed., 765) distinguishes dogmas from mathematical theorems, as well as from principles of the understanding, and proposes, as the technical definition of dogma, the following: --

(4) 'A direct synthetic proposition upon the basis of mere conceptions'; i.e. an assertion that, without the aid of mathematical construction, or of appeal to the general conditions which make our experience possible, asserts of a subject what is not involved in the mere definition of that subject. (J.R.)

Philosophy is interested rather in the problem regarding the sources of dogma than in dogma itself. Historically, very varied views have been held on this question. Roman Catholics derive dogma from revelation as given in the Scriptures, and from tradition, that is, authority. Theoretically, the early Protestants quarried dogma from the Scriptures; but, practically, a great deal of Roman Catholic dogma passed into their schemes through the medium of the Christian consciousness as a whole. This latter fact began to become plain early in the 19th century, especially when the historico-genetic method was articulated. Hence, the question was consciously put: From what source other than the Scriptures is dogma derived, seeing that there is another source? Here great divergence of opinion became manifest. Some, like Schleiermacher, J. T. Beck, Schenkel, and Plitt, relied on a subjective source -- 'pious self-consciousness,' 'conscience,' and the like. Others, like Martensen, founded on a quasi-objective source -- 'the perfect mediation between the ideas of the Scriptures and the ideas of modern civilization.' The problem has recently attracted fresh attention in philosophical circles, thanks to the attitude towards authority taken by A. J. Balfour in The Foundations of Belief, and the similar tendencies of Benjamin Kidd in Social Evolution. The fundamental fallacy attaching to the several discussions of this second source, regarded from a philosophical standpoint, is that they fail to analyse the process of thought of which dogma is a result.

Literature: this is enormous, and is fully given in Herzog's Real-Encyc. art. Dogmatik; HARNACK, Hist. of Dogma (Eng. trans.), i. 15 f., 359 f., vi. 33 f.; BALFOUR, The Foundations of Belief, 185 f.; WALLACE, Lectures and Essays on Nat. Theol. and Ethics, 73 f.; RITCHIE, in the Int. J. of Ethics, v. 107 f. (R.M.W.)

Dogmatics: Ger. Dogmatik; Fr.dogmatique; Ital. dogmatica. The name given to that section of systematic theology which deals logically with doctrine; it is otherwise called doctrinal theology.

Dogmatics has for its field all doctrinal questions connected with God; those relating to man as a religious being, and the subject of God's care; and those arising from the essential relationship between God and man following from the conclusions reached in the previous sections. The entire subject is bound up with the history of dogma, as a preliminary apparatus; and with speculative philosophy as an indispensable organon.

Literature: articles in the various theological encyclopedias, e.g. HERZOG; ROTHE, Theol. Encyc., 100 f.; SCHLEIERMACHER, Der christl. Glaube; LIPSIUS, Lehrb. d. Dogmatik; DORNER, Syst. of Christ. Doctrine (Eng. trans.); FRANK, Syst. d. christl. Gewissheit; KÄHLER, Die Wiss. d. christl. Lehre, ii; H. SCHULTZ, Grundr. d. evang. Dogmatik. (R.M.W.)

Dogmatism: Ger. Dogmatismus; Fr. dogmatisme; Ital. dogmatismo. (1) A form of philosophy which assumes a certain system of principles as its starting-point. Opposed to dogmatism are SCEPTICISM (q.v.) and CRITICISM (q.v.).

In the strict sense, any philosophy is dogmatic which avoids the Pyrrhonic scepticism. Every discipline must start with certain unproved assumptions. In the broader sense, an uncritical philosophy which makes unnecessary assumptions is called dogmatic. So the philosophy of the middle ages, which in the main took the teaching of the Church as a starting-point, is dogmatic.

The current distinction between dogmatism as a principle and dogmatism as a method is not well founded. Since dogmatism is simply the positing of unproved principles, any dogmatism involves a dogmatic method, and any dogmatic method involves dogmatism. (R.H.S.)

(2) Applied specifically to the philosophy of Christian Wolff, in whom the dogmatic tendencies of pre-Kantian philosophy, and notably of Leibnitz, are said to culminate. Kant himself was a disciple of Wolff in his 'dogmatic' or pre-critical period (see the histories of philosophy). For Fichte's use, see IDEALISM. Cf. DOGMA (3). (J.M.B.)

Dolichocephalic [Gr. dolicoV, long, + kefalh, head]: Ger. dolichocephal, langköpfig; Fr. dolichocéphale; Ital. dolicocefalo. Long-headed; the opposite of BRACHYCEPHALIC; having a cephalic index (ratio of maximum transverse diameter of skull or head to maximum anterior-posterior diameter) of considerably less than the normal; usually less than 75:100. If a further distinction is made between sub-dolichocephalic and true dolichocephalic, the former would include skulls with a cephalic index of 75.01-77.77:100, and the latter, of less than 75:100. Among dolichocephalic races may be cited West African negroes, Arabs, Kaffirs, &c. See INDEX (with illustration), and CRANIOMETRY. (J.J.)

Dolour [Lat. dolor, pain]: Ger. Schmerz; Fr. douleur; Ital. dolore. Bodily or mental pain or suffering, but particularly mental. It is characteristic of MELANCHOLIA (q.v.). (J.J.)

Dolus [Gr. doloV]: Ger. Dolus; Fr. dol; Ital. dolo. (1) A crafty act, intended to mislead another, and do him damage.

(2) A wrongful act of the above description. This is more precisely styled dolus malus (Dig., iv. 3, De Dolo Malo, 1, § 2).

Dolus, in the primary sense, was often justifiable or meritorious; as if the object of the craft and injury were a public enemy, or a robber. It was then dolus bonus (Dig., iv. 3, De Dolo Malo, 1, § 3). When there was no such excuse, it was dolus malus, and dolus is ordinarily used in Roman law in the meaning of dolus malus. Gross negligence was treated as tantamount to dolus (Dig., xvi. 3, Depositi vel Contra, 32); but only in determining civil remedies (Dig., xviii. 8, Ad Legem Corneliam, &c., 7). A special action lay for dolus, and it was the foundation also of a defensive exception. See Phillimore's Princ. and Maxims of Jurisprudence, xxviii; Sohm's Instit. of Roman Law, §§ 29, 72. Fraud, malice, or bad faith, does not seem to be an indispensable element in dolus malus (Dig., iv. 3, 18, § 5). 'Dolum ex indiciis perspicuis probari convenit' (Code, ii. 21, De Dolo Malo, 6). (S.E.B.)

Domestic [Lat. domesticus, belonging to the household]: Ger. (1) Haus-(Industrie), (2) heimisch; Fr. domestique; Ital. domestico. (1) Conducted within the home; thus the domestic system of manufacture is contrasted with the factory system. (2) Confined to the home country; thus domestic trade is contrasted with foreign trade.

In the development of modern manufactures, it is customary to mark three periods: that of the guild system, when the workmen controlled the capital; that of the domestic system, when the capitalist employed labour in the labourer's house; and that of the factory system, when he employs labour with buildings and machines of his own. The sweating system is a survival of the domestic system. (A.T.H.)

Domesticated Animals: Ger. Hausthiere; Fr. animaux domestiques; Ital. animalidomestici. Those which are kept for the service of man, or for his pleasure. It is not improbable that the choice of animals for domestication was originally limited to those which freely breed under the conditions imposed by man. (C.LL.M.)

The principal importance attaching to domestication, from the biological point of view, arises from the great and permanent change brought about in the animals' general conditions of life, e.g. of shelter, abundant food, artificial protection, limited breeding, &c., most of which result from artificial selection and afford scope for natural selection. The changes of a bodily kind are very great -- amounting in many cases to the production of morphological differences far exceeding those which separate the majority of allied species. Yet the absence of sterility inter se, as Huxley early insisted, separates such strongly marked races from true species (cf. Huxley and Poulton, as cited below).

Darwin points out that, as said above, the environmental changes are usually assisted by artificial selection or weeding-out carried to an extremely severe degree. And this consideration, it would seem, applies notably to the mental characters, e.g. temperament, intelligence, gentleness, cleanliness, &c., which are essential in the choice of house and yard animals; while physical characters, such as colour, shape, &c., are often of aesthetic, rather than of utilitarian, value. Domestication offers extraordinary opportunities for the experimental study of hereditary, variation, modification, hybridism, &c., and also for that of comparative psychology. (J.M.B.- E.B.P.)

Literature: DARWIN, in his Animals and Plants under Domestication (1868), has given a vast array of facts with regard to the origin of, and changes undergone through, domestication; HUXLEY, Darwiniana (1893); POULTON, Charles Darwin, 126, 129, 138. (C.LL.M.- E.B.P.)

Domicile (also written Domicil) [Lat. domicilium]: Ger. Wohnsitz. Domizil; Fr. domicile; Ital. domicilio. The place where one resides, with the intent to make it his home.

The domicile of a married man is ordinarily presumed to be the home of his family. Temporary absences do not affect a domicile; nor even a long residence elsewhere, when there is a continuing intent to return. 'Domicile of origin' is that existing at birth. It is that of the father or, in case of an illegitimate child, of the mother. A man's domicile, as it exists from time to time, is ordinarily that of his wife and minor children. 'Forensic domicile' is that which one has in view of the law, with reference to determining the forum before which he may sue or be sued. A domicile, under some systems of law, may be chosen for such a purpose, without disturbing the general domicile. An 'election of domicile' may also extend to a choice between two permanent and rightful domiciles, as in the case of a child, born in a country where his mother is temporarily sojourning, who at his majority can elect between his domicile of birth and his domicile of nationality. See French Code Civil, Art. 9.

'Et in eodem loco singulis domicilium non ambigitur, ubi quis larem, rerumque ac fortunarum suarum summam constituit, unde rursus non sit discessurus, si nihil avocet; unde cum profectus est, peregrinari videtur; quo si rediit, peregrinari iam destitit' (Code, x. 39, De Incolis &c., 7). (S.E.B.)

Dominicans: Ger. Dominikaner; Fr. Dominicains; Ital. Domenicani. The name given to the brethren of the Order of St. Dominic.

The society was founded in 1216. It was one of the mendicant orders, the members taking the vows of mendicancy, as well as those of chastity, poverty, and obedience. It soon made rapid progress, and is of importance to philosophy because Albertus Magnus and Thomas Aquinas sprang from its ranks. Later, some of the 'reformers before the Reformation,' like Tauler, Suso, Eckhart, and Savonarola, also belonged to it. It is usually understood that the promulgation of the dogma of the Immaculate Conception, by Pius IX, was a severe blow to the order.

Literature: HELYOT, Hist. des Ordres monastiques; CARO, St. Dominique et les Dominicains; KLEINERMANN, Der dritte Orden v. d. Busse d. heiligen Dominicus. (R.M.W.)

Donation [Lat. donare, to give]: Ger. Schenkung; Fr. donation; Ital. donazione. The technical name given to the edict (324) by which Constantine the Great is alleged to have made a portion of Italy over to the Papacy as a gift. The matter belongs to the larger discussion of the temporal power. The edict was not known till the 8th century, and it was exposed by Laurentius Valla.

Literature: DANTE, Inferno, xix. 112 f.; MÜNCH, Ueber d. erdichtete Schenkung Constantins d. Grossen; MACK, De Donatione a C. M. sedi Apost. oblata. (R.M.W.)

Donatists: Ger. Donatisten; Fr. Donatistes; Ital. Donatisti. The name given to a sect of the Christian Church in Roman Africa early in the 4th century.

It was probably derived from Donatus Magnus, bishop of Carthage. During the Diocletian persecution, a wave of enthusiasm led Christians to suffer every extremity for their faith. Consequently, any one who gave up his Bible to the civil authorities came to be called a traditor, and incurred much odium. The Donatists held that no traditor could effectively fulfil the functions of the priesthood, and especially of bishop. This view led to an open schism over the election of a bishop of Carthage in 311; the controversy continued for a century, and caused serious disorders till, in 411, a conference was held at Carthage between the Donatist and Catholic parties -- the latter being championed by Augustine. As a result, the Catholic view was affirmed; but the Donatist party, despite the rigours of civil persecution, maintained itself till the 7th century, when it was submerged, with the rest of the Christian community, by the Saracen invasion. The controversy is interesting for philosophy of religion, as having elicited some of Augustine's most effective work on the relation between God and man, and on the meaning of Catholicity.

Literature: OPTATUS MILEVITANUS, De Schismate Donatistarum; RIBBEK, Donatus u. Augustinus; DEUTSCH, Drei Actenstücke z. Gesch. d. Donatismus; VÖLTER, Der Ursprung d. Donatismus; HARNACK, Hist. of Dogma (Eng. trans.), v. 38 f., 140 f. (R.M.W.)

Donders' Law: Ger. Donders'sches Gesetz (der Augenbewegungen); Fr. loi des mouvements des yeux, de Donders; Ital. legge di Donders. With parallel lines of regard 'every position of the line of regard in relation to the head corresponds to a definite and invariable torsion value.' In Helmholtz' language: 'With parallel lines of regard the angle of torsion in both eyes is a function only of the angles of vertical and lateral displacement.'

Donders' law is important (1) for sure and easy recognition of direction in the field of regard, and (2) for the apprehension of the movement of objects in the field when the eye itself has moved. It was named after Donders by Helmholtz. See ORIENTATION (law of constant).

Literature: DONDERS, Nederlandsch Lancet (Aug., 1846), and Holl, Beitr. zu d. anat. u. physiol. Wissenschaften (1848), i. 105, 384; HELMHOLTZ, Physiol. Optik (2nd ed.), 619; WUNDT, Physiol. Psychol. (4th ed.), ii. 119; HERING, in Hermann's Handb. d. Physiol., III. i. 474; AUBERT, Physiol. Optik, 653; SANFORD, Course in Exper. Psychol., expt. 131. (E.B.T.)

Donum superadditum [Lat.]. A phrase which has occurred in the controversies concerning the question, 'What did Adam lose when he fell -- was his loss of something natural to him, or of something bestowed upon him supernaturally (donum superadditum)?'

Protestants tend to hold that Adam lost something which was a part of his proper nature as human. Roman Catholic theologians hold that he lost divine grace, and that this was a donum superadditum, i.e. it formed no part of Adam's essence, but was an accident -- something bestowed by divine power. The question is of no importance for philosophy of religion, except in so far as it involves the question of the possibility of man's natural knowledge of God, a denial of which would be easy from the standpoint of the donum superadditum theory. (R.M.W.)

Double Aspect Theory: Ger. psychophysischer Parallelismus (not an adequate equivalent, unless connected with the identity theory of mind and body -- K.G.); Fr. théorie de l'unité à deux faces; Ital. teoria del doppio aspetto. The theory of the relation of mind and body, which teaches that mental and bodily facts are parallel manifestations of a single underlying unity.

The double aspect theory acknowledges the incomparability of material and conscious processes, and maintains the impossibility of reducing the one to the other, in terms either of materialism or idealism (spiritualism). It professes to overcome the onesidedness of these two theories by regarding both series as only different aspects of the same reality, like the convex and the concave views of a curve (G.H. Lewes); or, according to another favourite metaphor, the bodily and the mental facts are really the same facts expressed in different language. The most characteristic feature of the theory is its strenuous denial of the possibility of causal interaction between body and mind, or vice versa, in deference to they supposed necessities of the law of the conservation of energy. For interaction it substitutes parallelism or concomitance. Each side seems to 'get along by itself,' or rather, as Bain puts it, 'we have always a two-sided cause. The line of causal sequence is not mind causing body, and body causing mind, but mind-body giving birth to mind-body' (Mind and Body, 132). This doctrine of 'a double-faced unity,' as Bain calls it, has more recently appropriated to itself the name of MONISM (q.v.). In stating the theory, the main stress is frequently laid upon the unbroken sequence of the material facts; in that case the theory approximates the doctrine of conscious automatism, and the position becomes practically indistinguishable from the more 'guarded and qualified materialism' with which Bain, indeed, in the volume referred to, appears to identify it (cf. Mind and Body, 140). Wundt, on the other hand, while accepting the principle of psychophysical parallelism in an empirico-psychological reference, gives it ultimately a metaphysical interpretation which brings it nearer to an idealistic position. The theory, therefore, while professing to harmonize materialism and spiritualism, occupies a position of somewhat unstable equilibrium between the two, and shows a tendency in different expositors to relapse into the one or the other.

The doctrine of parallelism appears as a metaphysical theory in Spinoza, for whom thought and extension are parallel and coordinate attributes of the one substance. 'Ordo et connexio idearum idem est ac ordo et connexio rerum' (Ethica, ii. 7). 'Obiectum ideae humanam mentem constituentis est corpus, sive certus extensionis modus actu existens, et nihil aliud' (ii. 13, with its Scholion, 'omnia, quamvis diversis gradibus, tamen animata sunt'). As revived in this century, it owes its currency (1) to the advance of physiological psychology, which demonstrates the closeness of the connection between the material and the mental; (2) to a perception of the crudity of pure materialism; (3) to the formulation of the doctrine of the conservation of energy, which is sometimes understood as implying that the physical universe is a closed cycle of energy-transformations. W. H. Clifford, Romanes, and perhaps Spencer, together with Wundt, Höffding, and Paulsen, may be mentioned as representatives of the theory in one or other of its forms. The position of Shadworth Hodgson and Professor Huxley is rather to be described as AUTOMATISM (q.v.).

Literature: see MIND AND BODY. (A.S.P.P.)

Double Images: Ger. Doppelbilder; Fr. images doubles, diplopie; Ital. diplopia, vista doppia. The images of a luminous point that stimulates retinal points situated beyond the limits of binocular correspondence (see CORRESPONDING POINTS), and is therefore seen double by the two eyes. For the general phenomena of 'seeing double,' see DIPLOPIA.

Literature: HELMHOLTZ, Physiol. Optik (2nd ed.), 841; AUBERT, Physiol. Optik, 605; HERING, in Hermann's Handb. d. Physiol., III. i. 397, 424; SANFORD, Course in Exper. Psychol., expts. 208, 211, 220. (E.B.T.)

Double or Multiple Personality: see PERSONALITY (disorders of). (J.J.)

Double (Negation, &c.): see MOOD (in logic).

Doubt [Lat. dubius, uncertain, prob. from duo, two]: Ger. Zweifel; Fr. doute; Ital. dubbio. Lack of belief under circumstances in which belief is felt to be possible.

In the article on BELIEF (q.v.), it is seen that certain complex intellectual conditions are preliminary to it. When these conditions are consciously present, but the assurance or consent of belief is not yet secured, there is doubt. Positively, this state of mind is due to a certain lack of harmony (seen in the derivation of doubt and Zweifel) among presentations, variously described as contradiction, contradictory representation, inconsistency; and negatively, as lack of evidence, unreality, both of which points of view are considered under BELIEF.

Literature: see under BELIEF. (J.M.B., G.F.S.)

Doubt (in logic). Primarily the state of mind relative to a proposition requiring evidence but not having, for either its truth or its falsity, evidence that is sufficient. The implied reference is always psychological, and the state is definable in relation to belief and disbelief, not in relation to knowledge pro or con. (R.A.)

Doubt (insanity of): see DOUBTING MANIA.

Doubting Mania: Ger. Zweifelsucht, Grübelsucht; Fr. folie du doute; Ital. follia (or monomania) del dubbio. This disorder, which has received various names (see art. Doubt, Insanity of, in Tuke's Dict. of Psychol. Med.), may be most naturally described as an abnormal self-consciousness in the direction of great hesitation and doubt, combined with more or less impairment of the will. The main symptom, haunting doubt, may be regarded as a form of fixed imperative idea from which the patient finds no escape.

Sufficient cases have been described, in which this symptom is apparently the only divergence from normal mental action, as to lead to their classification as cases of insanity of doubt. The disease seems to affect frequently, but not invariably, those hereditarily disposed to mental disorders; it progresses usually with periods of intermission, and as a rule remains incurable. The patient often maintains a long struggle against his morbid ruminations, and is perfectly aware of their unreasonable character; he retains, as long as he can, his place as a useful working member of society, but in the end withdraws more and more within himself, and frequently voluntarily seeks admission in an asylum. The cases vary considerably; a few types may be described. A characteristic form of the mania is of a metaphysical character; the subject doubts his own existence, questions the evidence of his senses, speculates as to the precise and ultimate causes of every detail and trifle, and recurs unceasingly to the same topic, repeating the same arguments pro and con, and with all forms of subtleties and hair-splitting considerations. This form of mental rumination may be confined to one special topic; frequently it is numbers (cf. ARITHMOMANIA), such as an irresistible impulse to count everything. Another class are morbidly scrupulous and conscientious, fearing lest they may have done wrong, may have failed to do their precise and literal duty; they dwell upon the most trifling and improbable circumstances, and often come to a standstill in their actions by reason of such fear. Others are constantly anticipating accidents, are in dread that somebody may fall out of a window at his or her feet, may speculate as to what should be done, and so on. Somewhat different, but frequently mentioned in the same connection, is the fear of contact with objects. The patient lives in a constant dread of contamination, and regulates his action, and allows his thoughts to dwell unnecessarily upon these considerations. Some of these forms have received special designations, such as metaphysical mania, reasoning mania, arithmomania, &c.

Transitory and slight tendencies to almost all these habits may be recognized by all as normal at certain periods. The abnormality consists in their persistence and absorption of the intelligence to the exclusion of normal thought and action. See INSISTENT IDEAS, and WILL (defects of).

Literature: LEGRAND DU SAULLE, La Folie du Doute (1875); RITTI, Gaz. Hebdomadaire, No. 42 (1877); GRIESINGER, Arch. f. Psychiat. (1868-9), i. 626 ff.; BERGER, Arch. f. Psychiat. (1876), 237; B. BALL, art. Doubt, Insanity of, in Tuke's Dict. of Psychol. Med.; MAGNAN, Recherches sur les Centres nerveux (2e sér.); BALLET-MORSELLI, Le Psicosi (1896). Also works cited under DEGENERATION. (J.J.)

Drama: see CLASSIFICATION (of the fine arts).

Dream [ME. dreme]: Ger. Traum; Fr. rêve; Ital. sogno. Conscious process during sleep.

Theories of dreaming are still unconvincing; even the description of the facts is incomplete. There is doubt (1) as to the condition of the attention (is it absent, or is it fixed, as in hypnotic somnambulism?); (2) as to movement (do we tend to carry out our images in movement less or more than in waking life?); (3) how much mental control is there in dreams? (4) what are the physical conditions of dreaming (anaemia or hyperaemia of the brain? -- dissociation over a large area, or lack of inhibition from a particular centre? -- how is dreaming related to the physical recovery due to sleep?); (5) as to sleeping without dreams (is it possible?). The discussion of these questions waits upon an adequate theory of SLEEP (q.v.).

Literature: see under SLEEP. Possibly the best general work is S. DE SANCTIS, I Sogni (1899). (J.M.B., G.F.S.)

Dream (anthropological). The phenomena of dreams played an important part in primitive culture. The so-called Dream-theory holds that from them, in part, arose the notion of a soul separate from the body, and surviving the dissolution of the body; for the visions of the dreamer were readily interpreted as the excursions of his soul into other regions, and the report back to his waking soul of what had been there experienced. As the dead were frequently dreamt of, such excursions were located in the after-life into which the soul went, when it no longer returned to the body; while the phenomena of trance, and delirium, and madness were looked upon as the possession of the affected persons by the souls of others. Dreams also were regarded as significant for, or prophetic of, the future; and thus arose more or less elaborate systems of dream-interpretation (Oneiromancy), which became part of the craft of the wise man, or magician. See ONEIROLOGY, DEMONOLOGY, and MAGIC. (J.J.)

Literature: TYLOR, Primitive Culture; SPENCER, Princ. of Sociol., i. (L.M.)


Drobisch, Moritz Wilhelm. (1802-96.) Born and educated at Leipzig, where he became professor of mathematics (1826) and philosophy (1842). He was the first to bring the writings of Herbart into prominent notice.

Drugs and Poisons (effects of): see INTOXICATION, and PSYCHIC EFFECTS OF DRUGS. (J.J.)

Drunkenness [from drink, AS. drincan]: Ger. Betrunkenheit; Fr. ivresse; Ital. ubbriachezza. A state of alcoholic intoxication. See ALCOHOLISM, and DIPSOMANIA. (J.J.)

Druses [probably from Ismail Darazi or Durzi]: Ger. Maroniten; Fr. Druses; Ital. Drusi. A Syrian people, whose religious history is well known, but whose ethnology and religion are still obscure. They are agnostic theists.

Their doctrine of a supreme and unknowable deity is accompanied by many fantastic elaborations. God was incarnated ten times, on the last and final occasion in the person of Hakim, the sixth of the Fatimite caliphs (1016 A.D.). The Universal Intelligence is the greatest of God's creatures, and alone can hold intercourse with him. Below this are numerous ranks of subordinate spirits. The doctrine of metempsychosis is held. The religion is closely connected with the aberrations of some Mohammedan sects, particularly the Batinya branch of the SHI'ITES (q.v.). The Druse doctrine of incarnation, however, separates them entirely from the essential principles of Islam.

Literature: DE SACY, Exposé de la Religion des Druses; CHURCHILL, Ten Years' Residence in Mount Lebanon; CARNARVON, Recollections of the Druses; GUYS, La Théogonie des Druses; arts. in Encyc. Brit. and in Herzog's Real-Encyc. (R.M.W.)

Dual (Relative, &c.): see LOGIC (exact).

Dualism (in art) [Lat. duo, two]: Ger. Dualismus; Fr. dualisme; Ital. dualismo. The view which holds to an actual external beauty, apart from the perception of it. See REALISM (aesthetic). (J.M.B.)

Dualism (in philosophy). (1) A general tendency to divide any genus of objects of philosophical thought into two widely separate categories, as saints and sinners, truth and falsehood, &c.; opposed to the tendency to look for gradations intermediate between contraries. Especially (2) any theory which explains the facts of the universe by referring them to the action of two independent and eternally coexistent principles. Cf. PLURALISM. (C.S.P.- A.S.P.P.)

Dualism appears as a religious theory in connection with the question of good and evil; and Zoroastrianism, with its opposition of Ahriman, the principle of darkness and evil, to Ormuzd, the principle of light and goodness, is usually cited as typical. But in so far as the system teaches the ultimate triumph of Ormuzd, even Zoroastrianism hardly abides by an ultimate dualism, and later sects sought to rise to a higher unity by representing Ormuzd and Ahriman as twin sons of a more fundamental principle called Zrvana Akarana, or limitless time. The dualism of Zoroaster reappeared within the Christian Church as the Manichaean heresy. Within the present century J. S. Mill, in his posthumous Essay on Religion, expressed the view that a dualistic theory was, on the whole, most in accordance with the facts to be explained.

In a purely metaphysical reference, dualism is connected with the opposition of matter and spirit, and signifies the assertion of the two as independent, co-eternal, and equally necessary principles. In ancient philosophy, the conception of spirit as consistently immaterial was first realized by Plato. Plato regards the ideas as alone truly existent, but he finds it impossible to explain the world of phenomena without a second principle of non-being or necessity, the so-called Platonic matter, as the groundwork of sensuous existence and the explanation of imperfection and evil. In the ethical turn given to the metaphysical opposition, the strong bent of Plato's own mind may be recognized, and perhaps also the influence of Oriental ideas. Aristotle's philosophy is essentially an attempt to overcome the Platonic dualism by a profound application of the notion of development, the Aristotelian prwth ulh being defined as mere possibility. But, as a matter of fact, says Zeller, 'matter acquires in Aristotle a meaning which goes far beyond the concept of simple possibility. From it arise natural necessity (anagkh) and accident (automaton and tuch), which limit and encroach upon the power which nature and man have of realizing their aims. It is due to the resistance of matter to form that nature can only rise by degrees from lower forms to higher; and it is only from matter that Aristotle can explain that the lowest special concepts diverge into a number of individuals. It is obvious that matter thus becomes a second principle besides form, endowed with a power of its own' (Outlines of Greek Philos., § 56).

In Neo-Platonism, the notion of emanation is employed to bridge over the gulf between matter and the supra-essential Deity, while in Christian thought the knot is cut by making God the Creator of the material world. The influence of the Platonic dualism on the Christian consciousness may be traced practically in the tendency to asceticism, and, generally, in what has been termed 'other-worldliness.' Typical thinkers of the Renascence period, on the other hand, like Paracelsus and Bruno, in their revolt against mediaeval thought, proclaimed the unity of spirit and matter in all that exists, and thus preluded to the doctrine of Leibnitz or more modern scientific monism. Meanwhile, the advance of science, by clarifying the conception of matter, emphasized the contrast between the inner world of consciousness and the outer world of extended mechanically moving things. Modern philosophy opened accordingly, in Descartes, with a reassertion in its extremest form of a dualism between the res cogitans and the res extensa, which thus became a problem for his successors. Spinoza reached a speculative monism by reducing both thought and extension to attributes or aspects of the unica substantia, while Leibnitz, emphasizing activity as the essence of substance, conceived the universe as a harmonious system of spiritual or quasi-spiritual forces. But this monistic idealism was abandoned by the Wolffians, and their dualism reappears in the various unreconciled oppositions of the Kantian philosophy -- between understanding and sense, phenomena and noumena, practical reason and desire. The chief post-Kantian systems are attempts to reach a doctrine of speculative monism which shall transcend and embrace the dualistic elements of the Kantian philosophy.

If the relation between mind and body be treated as a special question, to be solved without prejudice to the ultimate metaphysical issue, the term dualism may be used in a more specific sense -- as opposed alike to subjective idealism, materialism, and so-called monism (the double aspect theory) -- to denote a theory which represents the relation between the material world (acting through the body) and the mind as one of causal interaction between real things. The further question then remains whether these interacting and relatively independent substances can be harmoniously included in a single system or life. Cf. CAUSE THEORY, and MONISM.

The term dualism appears to have been first used by Thomas Hyde in his De Religione veterum Persarum (1700). It was used by him in a religious reference, and Bayle in his article on Zoroaster gave currency to it in the same sense. Wolff was the first to use it as applied to the opposition of mind and matter. Wolff frequently divides philosophers into dogmatists and sceptics, the former being subdivided into monists and dualists, the monists being again divisible into idealists and materialists, and the idealists, finally, into egoists and pluralists. Hamilton uses the term much in the Wolffian sense with special reference to the theory of perception. Natural dualism, or NATURAL REALISM (q.v.), is the name he gives to the doctrine of Reid and the Scottish school, which asserts 'an immediate knowledge by mind of an object different from any modification of its own.' 'The Ego and the Non-Ego are thus given in an original synthesis, as conjoined in the unity of knowledge, and in an original antithesis, as opposed in the contrariety of existence. In other words, we are conscious of them in an indivisible act of knowledge together and at once, but we are conscious of them as, in themselves, different and exclusive of each other' (Lects. on Met., i. 292). The term Hypothetical Dualist is applied by Hamilton to 'the great majority of modern philosophers,' because, while maintaining the existence of an independent external world, they deny 'an immediate and intuitive knowledge' of it.

Literature: see PHILOSOPHY, and METAPHYSICS. (A.S.P.P.)

Dualism (in theology). Dualism has appeared sporadically in theological inquiries, and can hardly be said to be a determining standpoint constantly, as has so often been the case in philosophy; it is a consequence, not a presupposition. Its appearances may be classified under four heads: (1) The theological, strictly so called. Here dualism leads to the dogma of two deities -- a good and an evil, as in the old Persian religion. This point of view usually crystallizes when the oppositions, obviously present in the world, assume the guise of enigmas, and when, as a result, unreason must be forced to bear its part in furnishing a hypothesis. Christian theology, taken as a whole, has been comparatively free from such lapses: whether it has won its freedom logically is another affair. It has been forced to deal with the problem of evil in its most acute form, that is to say, after the evil in the world -- which so pressed on the old Celtic religion -- and moral evil -- which affected the old Persian religion -- had both been fully set forth. Its dualism has been permissive: the devil being a creature of God, and not an independent power. (2) Anthropological. In its conception of man, theology is thoroughly dualistic. Body is sharply distinguished from soul; and the latter is conceived to be destined to existence in some sort of independence of the former, that is, the two possess separate reality. The doctrine of trichotomy -- according to which man is divided into body, soul, and spirit -- does not affect this fundamental dualism; for, on this plan, soul really becomes identical with vitality, a characteristic shared by man with the animals, and spirit takes the place of soul on the ordinary division of dichotomy. (3) Soteriological. Here, too, theology is fundamentally dualistic. It posits a God separate from the universe, and especially from man -- a God who has certain self-conscious purposes in regard to salvation, which he is working out on the human race. It may be said that it is difficult to see how the anthropological and soteriological points of view can be reconciled with the results of modern inquiry, especially as these are systematized by prevailing types of monistic philosophy. (4) (a) Social (with regard to the constitution of society as a whole). This dualism is purely historical, and finds its most eminent illustration in the dualism between the church and the world, the religious and the civil life, so characteristic in the centuries lying between the complete formation of the organization of the Latin Church and the Reformation. (b) Social (with regard to the individual man). Here we come once more upon a question that still retains vitality. The dualism between faith and knowledge marks this division. It is closely connected with the principle of authority. See FAITH. (R.M.W.)

Dullness [ME. dull]: Ger. Dummheit, Stumpfsinnigkeit; Fr. stupidité, lenteur; Ital. torpore. Lowered or sluggish activity.

Dullness in a sense organ appears as a relative insensibility, in that a given stimulus makes a much slighter impression than would normally be the case; or the impression may be ill-defined and vague, or develop slowly, such defect in extreme degrees amounting to ANAESTHESIA (q.v.). In regard to mental operations, dullness refers particularly to slowness, though also to limited scope of mental powers. Persons who come entirely within the normal range of variation of mental ability might be called dull; if still more deficient, they might be termed weak-minded. Dullness may also refer to special forms of mental deficiency, as dullness of the emotions, or of the moral sensibilities. (J.J.)

Dumbness: see DEAF-MUTISM, and SPEECH (defects of).

Dumbness (psychic or mental) [AS. dumb]: Ger. psychische Stummheit; Fr. mutisme psychique; Ital. mutismo psichico. Inability to frame one's meaning in the customary words; and aphasic defect.

'A distinction is legitimate between psychic and cortical dumbness, corresponding to the current distinction on the sensory side. Just as there is a distinction between being unable to hear words (cortical deafness) and being unable to understand the meaning of words we hear (psychic deafness), so there is a distinction, shown pathologically, between being unable to speak words and being unable to express our meaning in words' (modified from the writer's Ment. Devel. in the Child and the Race, 1st ed., 437; the term was first suggested in the Philos. Rev., ii., 1893, 389). Cf. BLINDNESS (psychic), and DEAFNESS (psychic). It is a narrower case of paraphasia or of 'inco-ordinate amnesia' (Bastian), the ground of the defect being, in contrast with other cases, in the higher motor or expressive functions. Séglas calls a special case of it 'mutisme hystérique' (Les Troubles du Langage, 97 f.). It illustrates the general motor defect called Psychic Paralysis under LOCALIZATION (cerebral) (q.v.). (J.M.B.)

Dunamis [Gr.]: see GREEK TERMINOLOGY (Glossary, dunamiV), and POWER.

Duns Scotus, Joannes. (cir. 1265-1308.) A scholastic theologian and philosopher, surnamed the 'Subtle Doctor.' The English, Irish, and Scots, all claim him a countryman. Said to be of gentle rank, and to have studied at Oxford. Became a Franciscan friar, and in 1301 professor of theology at Oxford. Moved to Paris in 1304, and taught theology with great success. A realist in philosophy, he opposed Thomas Aquinas, and founded the school of Scotists who for centuries opposed the Thomists.

Duration: see TIME, and TIME SENSE.

Duration, Least (experiments on) [Lat. durare, to continue]: Ger. kleinste Dauer; Fr. durée minimale; Ital. durata minima. The least time in which a given mental event may occur with normal distinctness; that is, without fusion, or confusion, with earlier or later events.

For example, the duration of a series of sounds at the maximum rapidity at which they are clearly distinguished from one another, divided by the number of intervals between the successive sounds, gives the 'duration' of one. It is necessary that the term duration, with this meaning, should be qualified by the word 'least' (or 'lower limit of'), seeing that the determination of duration in other connections (in reaction-time and time-sense experiments) concerns the 'normal' or the 'maximum' time taken up, and not the 'least' time. (J.M.B.)

Experiments on duration have been made upon certain mental processes (cf. Külpe, Outlines of Psychol., 30, 238, 382 ff.; Wundt, Outlines of Psychol., 143). The duration of a sensation varies with the conditions of stimulation. Pressures of moderate intensity appear to last about 1/20 to 1/30 sec., deep tones last about 1/25 sec., mid-region tones 1/45 to 1/70 sec., high tones 1/100 to 1/200 sec.; visual sensations (direct vision, without after-image) last from 1/20 sec. upwards. The duration of the idea in the 'train of ideas' has been estimated at about 3/4 sec. See TIME SENSE, and REACTION TIME.

Literature: HELMHOLTZ, Physiol. Optik (2nd ed.), 480 ff.; MARBE, Philos. Stud., ix. 384; HENRY, Compt. Rend. (1896), cxxiii. 604; v. KRIES, Zeitsch. f. Psychol., xii. 81; KUNKEL, Pflüger's Arch., ix. 197, xv. 27; EXNER, Wien. Akad. Ber. (1868); Pflüger's Arch., xiii. 234; URBANTSCHITSCH, Pflüger's Arch., xxv. 323; STUMPF, Tonpsychologie, i. 211, &c.; MAYER, Amer. J. of Sci. and Arts (Oct. 1874, Apr. 1875); R. SCHULZE, Philos. Stud., xiv. 471; ABRAHAM and BRÜHL, Zeitsch. f. Psychol., xviii. 177; SCHWANER, Diss. (Marburg, 1890), 37; SERGI, Zeitsch. f. Psychol., iii. 175; v. WITTICH, Pflüger's Arch., ii. 329; TRAUTSC OLDT, Philos. Stud., i. 213; KRAEPELIN, Tagebl. d. Naturforscherversammlung z. Strassburg (1885); GALTON, Brain (1879), 149; MÜNSTERBERG, Beiträge, i. (E.B.T.)

Duty [OF. deuté, from Lat. debere, to owe]: Ger. Pflicht; Fr. devoir; Ital. dovere. Literally, a debt; what is required of a man by the moral law; or, more strictly, the relation of the moral law to a moral person, whose will can be swayed by other motives than the consciousness of the law.

The conception of duty, in the form which it takes in modern ethical thought, has been formed by a variety of causes: chiefly (1) the analysis of moral conceptions -- including that of to deon, what is necessary or required -- by Plato and Aristotle; (2) the influence of the Stoic writers, by whom to kaqhkon, the fitting, was held to be determined by reason, apart from the emotional nature of man; (3) the Jewish and Christian conceptions of the moral law as declared and enforced by God. Under these influences, and that of the Roman jurists, who were themselves under the influence of the Stoic philosophy, morality came to be expounded as a system of laws, obedience to which constituted the 'duty' of a moral agent.

Even when this juridical aspect is less prominent in the conception of morality generally, it always belongs to the conception of duty. In this way, however, the range of the conception is often narrowed. Bentham and the Utilitarian school regard duty as applying, not to everything which is in accordance with their ethical standard, but only to that portion of right conduct which is protected by an adequate sanction -- political, social, or religious (to which J. S. Mill would add personal or 'conscientious'). The presence of the sense of duty, or feeling of obligation, in the individual consciousness is explained as due to the pressure of these sanctions demanding obedience, and their conflict with anti-ethical tendencies: so that with the moralization of human nature the feeling of duty or obligation may be expected to disappear (cf. H. Spencer, Data of Ethics, chap. vii).

On the other hand, Kant and the moralists of the Intuitional school commonly regard duty as the fundamental conception of morals. With Kant it is the moral law or dictum of practical reason, in its bearing on a will which is subject to other than moral or rational motives. (W.R.S.)

Duty (in law): Ger. Verpflichtung, Verbindlichkeit; Fr. obligation, devoir; Ital. dovere. That active or passive furtherance of the rights of others which is enforced by law. See Holland on Jurisprudence, chap. vii. 74. Legal duty is correlative to legal right. To enforce a duty is to vindicate a right, whether it be a duty owed to the state as a whole, or to particular individuals. A duty of the latter class is a duty in personam. A duty owed to all our fellow-citizens, or to a large class of them, is a duty in rem, or an impersonal one. See Pollock's First Book of Jurisprudence, chap. iv. 81.

Literature: WOLFF, Instit. of the Law of Nature and of Nations, i. chaps. iv, v. (S.E.B.)

Dwarf [ME.]: Ger. Zwerg; Fr. nain; Ital. nano. A person of complete physical development, but of unusually small dimensions.

While such persons are sometimes well formed, there is usually a greater or less amount of either a lack of proportionality of the several parts of the body, or a decided malformation. In certain forms of idiocy, particularly cretinism, a stunted, dwarfish growth is frequent. It is frequently a stigma of degeneration. In common with giants, dwarfs have figured considerably in legendary lore, and are often the subject of much attention among primitive peoples; while the custom of retaining dwarfs at court to furnish amusement appears from Roman to modern English times. Anthropometrically and biologically, such cases are as interesting as extreme variation in height. See FREAK, and SPORT.

Literature: art. Dwarf in Encyc. Brit. (9th ed.); DE QUATREFAGES, The Pygmies (Eng. trans., 1895). (J.J.)

Dyad: see MONAD, and cf. Pythagoreanism under SCHOOLS OF GREECE.

Dynamic: see FORCE, POWER, DYNAMICS, and TERMINOLOGY (Greek, dunamiV).

Dynamic Economics: Ger. dynamische Oekonomik; Fr. économie dynamique; Ital. economia dinamica. (1) That part of the science which deals with flows instead of funds -- with rates of supply, demand, or income, instead of quantities pure and simple. (2) Popular, but less correct: that part of the science which deals with changes in the state of society, and therefore with shifting data instead of permanent ones.

Patten, who has written much on this subject, uses the second distinction. The practical evil attending its use is, that it implies that problems regarding rates of income are not dynamic, and can be solved by methods analogous to those of statical mechanics. Almost every economist except Newcomb has, at one time or another, been influenced by this fallacy. Even Marshall, who discusses clearly the limitations of statical analysis, often fails to abide by those limitations in practice. (A.T.H.)

Dynamic (Relation, &c.): see RELATION, and SYNTHESIS.

Dynamic Theory (of matter): see MATTER.

Dynamics [Gr. dunamikoV, pertaining to forces]: Ger. Dynamik; Fr. dynamique; Ital. dinamica. The science which treats of the laws of motion of bodies, as produced by the action of forces. Now proposed to be extended so as to include both branches of theoretical MECHANICS (q.v.). (S.N.)

Dynamogenesis [Gr. dunamiV, force, + genesiV, production]: Ger. Dynamogenesis, ideomotorisches Grundgesetz (K.G.); Fr. dynamogénie (dynamogénique); Ital. dinamogenesi. The principle according to which changes in the conditions of sensory stimulation of the nervous system always show themselves in corresponding changes in muscular tension or movement.

The term 'dynamogeny' is used for the fact (cf. James, Princ. of Psychol., ii. 379) covered by the principle of dynamogenesis. The adjective DYNAMOGENIC (q.v.) was earlier applied (Féré, Sensation et Mouvement) to slight differences of stimulation, considered as producing increased motor effects. The facts have been generalized as in the definition above, dynamogenesis being a sensori-motor principle of genetic value. The present writer (Feeling and Will, 281; as also Ladd, Psychol., Descrip. and Explan., 229), uses the phrase 'mental dynamogenesis' to express the psychologically equivalent principle, that every change in sensory consciousness tends to be followed by change in motor consciousness.

Stumpf holds, on the contrary, that the generalization is not justified, since a threshold of stimulation must be recognized, below which sensory changes are ineffectual. Yet the finer work in suggestion, and in the recording of motor effects, seems to show that the threshold is entirely relative. Moreover, the theory of threshold takes no account of dispositions, contrast effects, &c., which do not come clearly into consciousness, but which represent so-called subliminal stimulations. The conception of the brain in analogy with a storage battery for potential energy is possibly less reasonable than that which treats the entire nervous system in analogy with a highly charged electric system, in which all changes are equalized throughout all the parts.

Literature: BROWN-SÉQUARD, Physiol. and Pathol. of the Central Nerv. Syst. (1860), and Princ. Actions des Centres nerveux (1879); STUMPF, Ueber den Begriff der Gemüthsbewegung, Zeitsch. f. Psychol. xxi; also special citations given in the works referred to above, especially in JAMES, Princ. of Psychol., ii. chap. xxii, and titles under DYNAMOGENIC. (J.M.B., G.F.S.)

Dynamogenic. Any stimulus or influence which increases the available muscular power is termed dynamogenic. Thus if, while under the stimulus of music, one can exert a stronger pressure upon the dynamometer than normally, such influences would be termed dynamogenic. The term is also used in a more general sense in regard to the tendency of a stimulus to call out a motor response. See DYNAMOGENESIS.

Literature: BALDWIN, Ment. Devel. in the Child and the Race (1895), 165 f.; TRIPLETT, Dynamogenetic Factors in Pacemaking and Competition, Amer. J. of Psychol., ix. 501 ff. (J.J.)

Care should be taken to distinguish this form from the passive form dynamogenetic, which characterizes the motor change or result of the dynamogenic process. See GENESIS AND GENETIC. (J.M.B.)

Dynamometer and Dynamograph: see LABORATORY AND APPARATUS, III, A.

Dyne: see UNIT (of physical measurement).

Dyophysites [Gr. duo, two, + fusiV, nature]: Ger. Dyophysiten; Fr. Dyophysites; Ital. Diofisiti. The name applied to that party in ancient Christological controversy who held that the God-man had two natures.

The problem, 'How can the complete God and the complete man be united in one being?' naturally produced many conflicting solutions. The dyophysitic answer was as follows: -- The godhead of the Logos in Christ must be distinguished from the mortal body. The former is uncreate, the latter created. Birth, temptation, suffering, death, belong to the human nature, not to the divine. Mary was not the 'mother of God,' but bore the humanity of Christ. Nevertheless, there was one Person only; for the Logos, without transformation of self, took up into its substance the humanity, and this by an act of grace.

Literature: writings of PAUL of Samosata, DIODORUS of Tarsus, THEODORE of Mopsuestia, NESTORIUS of Constantinople, CYRIL of Alexandria; HEFELE, Conciliengesch. See APOLLINARIANISM, MONOPHYSITES, and NESTORIANS. (R.M.W.)

Dyotheletism [Gr. duo, two, + eqelhtoV, voluntary]: Ger. Dyotheletismus, Zweiwillenlehre; Fr. dyothélisme; Ital. diotelismo. The name given to one of the conclusions deduced from the doctrine that Christ had two natures.

Martin I and the Lateran Synod (449 A.D.) lay special stress on the necessity for attributing two wills to the two natures. He who denies the two wills -- who is a Monothelite -- denies the reality of the Incarnation. The problem is fundamental to the widely different development of Christological speculation in the West as contrasted within the East.

Literature: DORNER, Hist. of the Devel. of the Doctrine of the Person of Christ (Eng. trans.), Div. II. i. 164 f.; HARNACK, Hist. of Dogma (Eng. trans.), iv. 255 f. (R.M.W.)

Dys- [Gr. duV, hard, bad]: Ger. Dys- Fr. dys-; Ital. dis-. The use of this prefix indicates an imperfect, defective, or difficult form of the activity to which it applies. It is used (1) in a most general sense to imply any and all forms of imperfect action; and (2) in a specialized sense to denote a perverted or difficult form of action as opposed to absence of capability (prefix, a-, ab-), or to unusual presence (prefix hyper-). If distinguished from the prefix para-, it refers to difficulty of action, while para- refers to a perverted or false action. Examples: Dysphasia denotes either a general defect of speech of any kind, or difficulty in speaking. Dysboulia is an impairment of will action. Dysarthria is a defective articulation; Dyspepsia, impaired digestion, &c. (J.J.)