title: Elements of psychology
text: aO' s'!^'* ^ V' '^V^' <^ V ./' /^^v ' V..- ' yMM^ X /■ /; ^a>'b" vv J^> ,..., ^. I: ^..^^ ymM' x/ • ^' y ^* V* ♦ ' • ?' c o°^^;:>- ./-yi^'X .^°.-^^'°^ /^ • ""-ft* A*' \ ')^..LV1', *> r\ » • • • » *^ v^^ "o. "*-'t:t'''* A* / ,.>:^> ^-e, y ^ K ./^--. ■^v-^*'^ .*i ^/h.- '%, .;**' - 0^ ,«V'^ ^ -^-^•0^ ^^^ ^^/'^'•'** aC^^ <> 'o« in^ •*U.o< o V V y < o V •/ /'"^^^ ^^^/ -^'^"^'^^ °'w^^/\ --^ >"■'<#-. /°%.'.wf:^„o' x-^-^^^^ .^o^ -^o. p *j:^'* ^ L- '^^'rv .<^ '^^^^^^ ^^^^ ^Y .^% fv V ,. o » o * ♦> >* .l^nL'* iP-n^ ;^i^^; ^^q.. ^ <.^^ V o * • "' <^^ -^■''^^^^" \./ <> '••'• A<' ELEMENTS OP PSYCHOLOGY. J. Mr TAYLOR. oEP 17 1892 ) Privately printed for the use of College Classes. POUGHKEEPSIE, N. Y. : A. V. Halght, Printer, 12 Liberty Street, 1892. 'f- Entered according to act of Congress, in the j-ear 1892, by J. M. TAYLOR, in the office of the Librarian of Congress, at Washington. PREFACE. In the preparation of these notes the author has kept before him- self three or four distinct aims. He has felt the need of a brief text- book, for the sake of the student, and as inviting to fuller discussion in the class-room than is possible with a larger book. He has borne in mind that the general student will not pursue this study beyond the course compelled by the college curriculum, and has therefore deemed it necessary to state, for such, certain philosophical implications of psychological teaching. He has wished to encourage independent reading on the part of the student. The references are accordingly made to the general works within reach of the college student. They are but suggestions. The class-room furnishes abundant opportunity for their amplification. It seems important that the beginner should have some definite center from which to reach out. and the book therefore aims to make briet statements, in positive form, of the positions that seem to the author justified by the facts. The book is for beginners in Psychology, and does not aspire to be judged, as is the case with too many of our text-books, as a contribu- tion to psychological theory or knowledge. August, 1892. PSTOHOLOGT. PAGE. I. Definition (Empirical and Rational), .... 5-7 Consciousness (in brief). ... 6 II. Relations, 7 Physiology, Political and Social Science. Logic. Esthetics. Ethics, Theology. Physical Sciences. III. Value, 9 IV. Difficulties, ......... 10 V. Method, 11 VI. Divisions, 13 General Psychology. I. The Elements: Sensation, 15-32 Definition. The Organism. Varieties of Movement (Specific Energy.) Psychophysics. The Psychical and Physical in this Sphere. Classification of Sensations, 24 Special General and Taste, Smell, Temperature Sense. Muscular, Touch, Hearing, Sight. Object of the section. II. The Processes, 32-60 Initial Perception,. 32 Association, 35 Primary principles. 37 Secondary principles,. 43 COI^'TENTS. Theories suggested, 48 (a) Physiological, 48 (5) Chemical or Molecular, .... 50 Memory, ......... 53-59 Theories of Betention, 54 [a) Psychological, 54 Hamilton : Herbart , Wuiidt. (b) Physiological, 56 Maudsley, Bain, Baldwin, McCosh, Ladd. Recognition, 58 Cultivation of Memory, 59 Comparison, 59 Special Psychology. Perception, 61-76 Perceptions gained through various senses, . . 62 Taste and Smell, 62 Muscular sense, 63 Touch, 64 Hearing, 67 Sight, 69 Constructive, 73 Generalization, 76-82 Abstraction, 78 Classification 79 Denomination, 80 Judgment, 83 Reasoning, 84 Constructive Imagination : Idealization, .... 87 Abnormal Illustrations of Mental Activities, . . . 92-96 Dreams, 92 Somnambulism, 94 Hypnotism, 95 Constitutive Principles of Knowledge, .... 96-112 Consciousness, 96 Time, 105 Space, 106 Substance, 109 Trustworthiness of our knowledge, 112 Causation, 115 CONTEXTS. Reality of Subject and Object. Illustrative Historical Resume, The Feelings, The Xature of Feehng,. Note on Physical Basis. Note on Expression. The Nature of Pleasure and Pain,. Classification of Feelings, Influence of Feeling in Mental Life, TheWm, Antecedents to Voluntary Action,. Influence of the Will, Freedom of the Will, PAGE. 118 122 138-147 139 142 144 146 -153 148 150 151 14i PSYCHOLOGY. I. Definition : Psychology is the science which treats of the facts of the Mental or Psychical Life. By mental life is meant that which is expressed in any kind of consciousness^ — knowing, feeling, or willing. The common use of mental as identical with the first of these states, only, leads to the preference of the term psychical, as more technical and precise. But the word mental should be used as inclusiye of the three states here referred to. The facts of mental life include isolated phenomena, such as a single feeling, or sensation, — phenomena in com- bination, such as the mind's unification of a number of sensations in a single perception, — and processes, such as the association of ideas, or the recalling of past expe- riences. These may be treated as mere facts, objective to the inquiring mind, and may be established and classified, without inquiry as to the nature of the soul, and without effort to explain liotv the unity of the mental life may be explained in the face of the multitude of its experiences. Then we have Em2)irical Psycliology, the result of obser- vation and experiment. Or they may be so treated as to involve the further questions of the intelligent mind. What is the Mind, or Soul ? What is its relation to the Body ? "What is the na- ture of the object perceived ? Then we have Rational or Philosophical Psychology. While the scientific method compels us to first ascertain and classify ih^factSf the questions to which they lead can- not be avoided. Psychology must lead to Philosophy. While we shall aim to get the simple phenomena clearly 6 PSYCHOLOGY. before us we shall not hesitate to follow their indications into the realm of Ontology, or Metaphysics. Murray, p. 1. Sully, p. 1. Dewey, 1, 2, 3. Lotze, Outlines, Introd. Fleming, Vocab Bowne, 1.2. Baldwin, 1, 8. Lindner, Lehrbuch, 5 and 7. Janes, 10. Porter, 5, 6, Bowen's Hamilton, 84. Hill, 1. cf. Spencer, Psych. I, 129, 130, 140-1, on distinct^ of Psychology, Metaphysics, Ontology, cf. Seth, art. on Philosophy, Encyc. Brit., 9th ed. Consciousness, according to the definition, is the dis- tinguishing feature of psychical life. It must be discussed, by implication, in the investigation of every form of mental life, and it will be more fully considered when the more complex factors of that life are before us, but to avoid confusion it must be clearly defined at the outset. It is not a faculty (Reid), nor a feeling (many sensa- tionalists), for feeling exists only in consciousness, nor '' the complement of cognitive faculties," *^ the genus of which cognitive acts are the species '^ (Hamilton), for every faculty, in exercise, is conditioned on consciousness, nor ''i\iQ poiuer by which the soul knows its own acts and states ^^ (Porter), nor ^^the souFs power to know that it is itself that knows " (Hopkins) [not so in ^' Outline " cf. p. 107, 108], which makes consciousness a power turning attention to that which is known ex hypothesi in conscious- ness. It is rather a state, or condition, accompanying every exercise of the soul, an awareness of self and not- self, of self through the medium of a notself, " witli- Jcnowing." Feeling and Willing, therefore, as well as Knowing, are conditioned on conciousness. It is the life of the soul, involuntary, like life, and so to be distinguished from Cognition, being the spontaneous and invariable ac- companiment of every cognition of self or notself. The various divisions sometimes made, therefore, into spon- taneous, philosophical, self, consciousness, mark only va- rieties of degree, and not of kind. Every mental ex- PSYCHOLOGY. 7 perience involves consciousness, and every consciousness involves self, and notself. The development of consciousness is not here in ques- tion. It will be better discussed later. This definition makes clear the separation between the science of Psy- chology and every science which deals with unconscious phenomena [see under later discussion]. It is neither physical nor physiological : its field is a new order of phe- nomena. But it has to other sciences close relationship. Beferences.—hmdRev, 1, 2. Hill, 14. Baldwin, c, 4. Bowen's Hamilton, cc. 8-11. Dewey, 2. Murray, 2, B. Bascom, 210. Bowne, 235 sq. Wayland, 110 sq. Porter, 85 sq. McCosh, Cognitive Powers, 70, 71, 74. 83, 242. Fleming, on hist, scholastic, definitions, &c. Hopkins Outline Study, 106. II. Relations. 1. Physiology, (a) Connection. The influence of body on mind is too potent to need enforcement. The injury of the brain may result in loss of mental life ; close study prolonged exhausts brain-power ; sleep, refreshing the body, gives power to the mind ; disease of the brain produces illusions and insanity. It seems, too, to be established that certain mental func- tions depend upon the healthy condition of certain por- tions of the brain, as the power of speech on Broca^s con- volution, and that molecular changes accompany every exercise of thought. That the influence of mind on body is equally real is seen in the facts of medical science, in ^' Mind-cure,^' in familiar experiences of every life. None of these facts establish any other relation than that of co-ordination. {b) Separation. (1) All the facts of physiology are ob- jective. They occur in space, and are characterized by movement. If traced back as far as observation can go. 8 PSYCHOLOGY. they show no indication of consciousness. They lack the very elements which give psychology its reason for being. Thought is not marked by movement, nor by spatial re- lations. It is not objective. It is only known in con- sciousness. (2.) No possible reasoning can connect these two realms, so diverse in every particular. Even those whose general reasonings leave an impression of a closer connection than facts warrant, say explicitly that no passage is discover- able between molecular movement and states of conscious- ness. So Huxley (Fortnightly, Dec, '86), Tyndall, who declares the chasm '' intellectually impassable, '^ and Spencer,— Psych. 1 : 158, 161. (3.) The difference in sensations is not explicable through any difference in construction of nerves and cells. No explanation can even be suggested which does not imply another kind of existence, a discriminating, interpreting, consciousness. These movements have no meaning apart from it, and we distinguish ourselves from these. Baldwin, pp. 3-8. Bascom. Compar. Psych, c. 1. Sci. of Mind, 34. Lotze, Outlines, 9. Sully, 3-4. Porter, 16-40. Bowne, c. 1. Benedict, Pop. Sci. Mo , Ap. May, June, 1885. Taine, Intelligence, 185. Dewey, 37-44. Ladd, 633-667. Bain, Senses and InteUect, 11, 13. Lindner, 13, 13. The above makes evident what must be the value, and the limitations, of Physiological Psychology. This new science can only investigate and discuss laws which govern the relations of body and mind. From the nature of the case the study of Physiology, which is objective, wholly, and which must regard the body as a mechanism, can throw no light on the real nature of mental processes. On the other hand it can show the bodily conditions under which mental operations are possible, are hindered, or PSYCHOLOGY. 9 destroyed, or are encouraged, and so trace the correlations of the nervous organism and the mental life. Def . of the Science and compass, Ladd, Introd. , espec. § 3 and 8 (at end). Carpenter, Ment. Physiol. Introd., ch. 6. Wundt, Physiol. Psychologie, Einleitung, 1-7. (2.) Political and Social Sciences. All rest on certain assumed data which must be tested, at last, by psychological investigations. Jurisprudence, e. g. Theories of the State, and Society. (3.) Logic, as dealing with laws of thought must rest on investigation of origin and trustworthiness of thought. (4. ) Esthetics : the nature of the esthetic ideal, the analysis of the pleasurable and beautiful, lead us at once into psychology. (5. ) Ethics rests on certain assumptions regarding human nature which are tested only by psychological investigation. (6.) Theology justifies its conclusions by appeal to the nature of man, that is, by facts established by Psychology. (7.) Pedagogy, dealing with the training and instruction of the mind, is fundamentally a psychological science, and only the careful study of the mind^s operations, the natural order of development of the faculties, the results of various modes of training, can give one a sound theory of edu- cation. (8. ) The Physical Sciences. The very conceptions under- lying them, '^force,'^ ^' substance, ^^ ^^ cause, "^ ^' space," ''time,'' &C-, are ' philosophical, and their justification must be sought in psychological facts. Porter, §§ 13, 13. Sully, pp. 14-16. Dewey, 3, 4. Janes, 6, 7. Bowen's Hamilton, p. 13 sq. Seth, closing part of '* Philosophy," Encyc. Brit. 9th ed. III. Value. (1.) The great importance of the study is seen in the 10 PSYCHOLOGY. scope of its relations, just indicated. But we may add more particular considerations. (2.) Its help in enabling us to meet the problems which press on us, the question of Being, our own existence, the existence of the world external to us, — the question of Knoiving, how can we know ? what can we know ? what is the relation of the Self and Not-Self given us in experience ? Man's origin, capacities, destiny, are all in- volved. " The study of consciousness is the study of hu- manity." (Cousin). Self knowledge underlies all true knowledge. (3.) Our philosophical theories, expressed or unknown, shape our modes of thought and influence our investiga- tions and conclusions. (4.) In the light of the crass materialism of our time the value of the study is very great. (5.) Has the utmost importance in connection with the study of Hypnotism, Theosophy, " Christian Science," i&C. (6.) As mental discipline, the improvement of capacities and powers. Not native mental strength distinguishes the educated and uneducated so much as attention, clisc7Hmi- nation, definition, dear tliought. These are especially cul- tivated by this study. Bowen's Hamilton, pp. 6, 9, 10, 13 and 19 {note). Janes, 7-10. Porter, 10 sq. Bascom, Introd., 1-8. IV. Difficulties. The nature of the subject-matter of the science, and the unfamiliarity of most students with prolonged pro- cesses of observation of mental states, make the study dif- ficult. The looseness of language, also, the use of the same word, as "know," or "idea," or even '^sensation," and " perception," in several different senses, adds to the difficulty of exact statement. There is need of great care PSYCHOLOGY. 11 in this respect, and of patient cialtiyation of the habit of introspection and careful obseryation. Fleming, Vocab. (on above words). Bascom, 22 sq. V. Method. The subject-matter of this Science compels the use of the introspective method, but the chances of error in the subjective examination of the facts of consciousness and in the report and comparison of these facts and the limita- tion of introspection to the individual experience, necessi- tate the supplementing of this by the method of observa- tion and experiment. The results of mental life, in language, customs, history, must be used as tests of the so-called '^'^ deliverances of consciousness/^ Keligions and literatures must be studied for illustrations of the mind^s workings. (Volkerpsychologie). The growth of the men- tal powers must be watched in the infant, that we may see clearly what is original, and what the result of experience. (Infant Psychology.) Experiment upon the blind, or those deprived of any sense, must be used to show clearly the indebtedness of the normal mental life to each of the senses, and abnormal conditions, mental disease, hypno- tism, &c., must be studied as illustrations of the action, or inaction, of our powers where there is disturbance of normal harmony (Psychiatry). Physiological and physical experiments may also determine more clearly the relations of mental to physical states. (Psychometry.) The study of animal intelligence may throw light on the growth of mental life, as certain faculties are studied in simpler con- ditions. (Comparative Psychology). But in all these studies of external facts the ultimate appeal and test must be in consciousness itself, where alone the data are interpretable for us. Baldwin c. 2. Dewey, § 2. Hill, 4. Bascom, 19, 20. Sully 4 to 8, and app. A. McCosh, Cog. Powers, Introd. Bowne, 1-7, Porter, 51-60. Hamilton (Bowen, c. 4) Ladd, p. 10. 12 PSYCHOLOGY. The Introspective Method has been denounced as en- tirely unscientific, on the grounds that we never are able to observe the activity of consciousness, that we cannot pause to do it without losing from our grasp the conscious- ness we would examine, and that the supposition of the power to do this involves the division of self into observer and observed, simultaneously. The observation, moreover, is mdividiial, and so not exact for all, and necessarily narrow in range. But the mind has power to do precisely what is here denied, — to attend to its own states, to watch them in progress, to recall them immediately and to review them, to repeat and re-examine them. It can carefully compare results with those obtained by others, and thus reduce the errors of observation. Great care is necessary, from the nature of the subject-matter, but the objection is futile and baseless. Comte Positive Philos. (Transl.) 1 : 11. Maudsley Physiol, and Pathol, of Mind. pp. 10 sq. (Am. Ed.) Mill (adverse) Comte 59 (63 Eng. Ed.) Calderwood Moral Phil., 5 and 6. Hill, 5. Sully, 681-2, Martineau, Types, 2 : 4 and 5. The Experimental Method has made very exaggerated claims for itself, in sympathy with certain prevalent intel- lectual tendencies. Some of these claims will be noted in detail hereafter. Baldwin (29-31) has summed up the general considerations. Experiment deals chiefly with the lower mental activities, and even then often lacks in ex- actness, involving always a subjective side, and dealing with averages rather than individual results. It may well be asked, too, whether, if Psychophysics, for example, be- comes more exact, its results will prove of great value to Psychology. cf. Dr. McCosh, in Introd. to Ribot's Germ. Psych, of To-day (transl.) See Murray's § 2, a survey of the sciences whose study will aid in guarding against mistakes of introspection. PSYCHOLOGY. 13 VI. Divisions. An examination of the functions of the soul discloses intellectual, emotional, and volitional, powers, not entirely separated or separable in their action, not organs of the soul, but interrelated manifestations of mental life. In ancient Philosophy and among the Schoolmen, the division of these powers was based largely on Aristotle^s, the ISToetic and Orective, or Cognitive and Motive, the Understanding and Will of the later Schoolmen. Still later we find the Intellectual and Active Powers (Reid) corre- sponding to the old division. The feeling that this classi- fication left the sensibilities in an uncertain relation to both classes led to the introduction, in Germany, of the threefold division here given, and this was adopted by Kant, and made common in English thought by Hamilton. Largely through the influence of the latter the Cognitive Powers have been subdivided into Presenta- tive (or Acquisitive), Conservative, Reproductive, Repre- sentative, Elaborative, Regulative (or Intuitive). Many reduce these to four classes, placing the second and third under the fourth head. The Emotive, and Conative Pow- ers, or Feeling and Willing, are then treated separately. This division seems artificial and forced. There are cer- tain facts and processes common to all these experiences of the mental life, and underlying them all. The old di- vision compels us, therefore, in passing from one to an- other, to cross and recross these common tracks. Dr. J. Clark Murray has suggested a better classification of the science, which promises to make its way to general accept- ance. He divides the treatment of the subject into Gen- eral and Special Psychology, the first dealing with the ele- ments present in all phases of mental life and the processes of their combination, and the second with the nature of 14 PSYCHOLOGY. these combinations, as exhibited in the three general types of Knowing, Feeling, and Willing. Murray's Handbook of Psych,, 15, 17, 111 sq. Baldwin, c. 3 and pp. 80-1*. Sully, 20-25, and App. B. Hill, 7-9. McCosh, Cog. Pow. § 4 (Defense of '' Faculties" vs. Herbart: divides into Cognitive and Motive, cf. p. 15). Hamilton I, 123 (Bowen's Ham., 76-81, 120, 275, or Murray's Ham., 66). Porter, 40-50. Spencer, I : 142. Bain, 6-9. Wundt, 11-18 (on the 3-fold division in Germany.) GENERAL PSYCHOLOGY. I. The ELEMEis^TS : Sexsatiox. Definition. A sensation is an elementary consciousness excited by movement in the bodily organism. It is important to note carefully the implications of this definition. The word sensation is very frequently used with an objective reference, as if it were a pliysiological fact, an impression. It is not a movement, nor a nervous action, but a psychical fact, a conscious7iess. It is further defined here as elementary y because it is the simplest, undeveloped, reaction of the soul, or mind, against physical stimulus. It is the aim of every science to reach back to its ultimate and unanalyzable elements. These may be unknown in actual experience, as are atoms, e. g., but they must be assumed, and facts sustain the hy- pothesis. So in psychology our simplest perception of the external will be found to involve still simpler elements, that is, to be themselves capable of analysis. The elements thus discovered are sensations. As is implied, they are not found, in our developed experience, in independent ex- istence, but every such experience involves them, a simple, subjective condition, where no reference is made to the ex- ternal object, a feeling excited by a non-psychical stimulus. General refs. on Sensation, Definition, &c. Lotze, Outlines, 5-8. Dewey, c. 3. Ladd, 306. Bowne, c. 2. Bald- win {vs. Lewes' objective use, p. 82) 83-85. Porter (sense perception) 119 sq, espec. 127-8. SuUy, c. 5. Carpenter, 148, note. Bain, 117. Lindner, 27. HiU, 24-32. Murray, 18-23. The bodily organism is capable of awakening this con- sciousness, and is therefore called sensitive. The capacity is sensihility, and its special forms are the senses. This capacity is due to the nervous system. 16 GENERAL PSYCHOLOGY. Any detailed account of the nervous system must be sought in especial works on Physiology, such as Kirk's Handbook, — or Huxley's Lessons in Elementary Physi- ology. Here a bare outline of the subject will suffice, — and more special study may be left for later occasions, as they arise. Two systems constitute the nervous organism, the Cere- bro-spinal and the Sympathetic, the former including the brain, medulla oblongata, and spinal cord, — and the nerves proceeding from these, — and the latter consisting of certain ganglia, plexuses, and fibres, chiefly related to the viscera, and demanding no attention here. They have to do, mostly, with parts capable only of involuntary movements (Kirk, espec. 709-712). The cerebro-spinal system consists of grey, cellular, matter, found throughout the brain and spinal cord, and white fibrous matter. It is probable that the grey matter of the cord is not sensitive, though it may conduct some impressions which awaken sensation (Kirk — 545). The nerves (white and fibrous) which spread to every part of the body terminate in the cord, — and the fibres from these nerves are largely (about one-half) absorbed in the cord itself— (Kirk— 539). The nerves which enter the cord on the posterior portion are called Centripetal, or Afferent, — and convey im- pressions inward : those which proceed from the anterior portion of the cord, are the Centrifugal, or Efferent, and awaken motion. (See diagram in Kirk — p. 547). The Medulla Oblongata continues both the grey and white matter of the cord, — and is the center through which all impressions pass from cord to brain, and brain to cord. The brain also consists of grey and white matter, but here, unlike the cord and medulla, the grey matter is ex- ternal, and serves as a covering for the white. The white GENERAL PSYCHOLOGY. 17 , matter is still fibrous, but the sheath here gives place to a delicate tissue. The fibres are smaller than in the cord. This is the center of the whole nervous system, — and in this sense may be regarded as the cliief organ of mind. The nerves have no capacity in themselves for awaken- ing the conditions of their activity, but respond instantly to mechanical, chemical, thermal, and electrical, stimuli. They are mere conductors of impressions — (Kirk — 519, 520). The movement along a nerve-fibre, the nature of which is not understood, is very rapid, being estimated at 111 feet per second in motor nerves (Helmholtz) and at 140 feet in sensory nerves (V"on Witfcich, from Kirk — p. 521), under normal circumstances. The definition has indicated the necessity of movement to produce sensation, and the nature of the organism thus sketched illustrates the need. These movements may be of various kinds and degrees and they give rise to a great variety of sensations. They may be due to action in the organism itself, — to the involuntary movements which are the accompaniment of all life, — or to any external stimulus. The nature of the sensation must vary with that of the stimulus. According to the amplitude of a movement, the distance through which the body moves from a point of rest (as when we pluck a piano string), — will be the intensity of a sensation. According to the velocity of a movement will be the kind of the sensation. A sensation of hearing, e. g., is produced by vibrations ranging from about twenty to about thirty-eight thousand per second. Four hundred and fifty-one billions of vibrations give us the sensation we call red, seven hundred and eighty-five billions produce violet. 18 GEITERAL PSYCHOLOGY. Beyond these are the actinic and electric effects of move- ment. Again, movements may be regular, orderly, or ir- regular, with the the result of harmonious, pleasing, or confused, sensations. Are these varieties of movement a sufficient explanation of the varieties of sensation ? Or are we to look also to some specific energy of the nerves themselves ? Every re- action of the mind against a stimulus to the nerve ends of the fingers gives a sensation of touch : every such stimu- lus to the optic nerve produces sensations of light. Is this '' specific energy " true of the whole nervous system ? Is it an original property of these nerves, or, so far as it is true, is it acquired by use ? 1. Variety of movement, great as it is, and manifold in its effects, could not be a sufficient explanation, even if we could suppose that this vast variety was propagated, as such, through the nerves. 2. There is no discovered difference in the composition of the various nerves, — even those connected with special sense-organs, — and thus the hypothesis of original proper- ties must be set aside. This is true also of the internal nerve endings (Wundt 1 : 315). 3. Specific energy is a fact, as is seen in the deliverances of the special sense-organs. 4. Experiment would seem to have established a certain localization of functions in the brain. There has been much exaggeration in the claims of some of those teaching this view, — but it must be admitted, in a general way. There are no ^wch. fixed areas as some claim ; they overlap, and are indefinite. Nevertheless all parts of the brain are not involved in all its functions. Much depends on structure, and proper connections with the periphery are essential. But experiment also shows that the functions of one cerebral centre may be taken up by another, — GEITEEAL PSYCHOLOGY. 19 tliough this is generally true only of contiguous portions, or of corresponding parts of the other hemisphere. But cf from note Brown-Sequard on 17*. Ladd, 301-303. 5. Experiment also points to the establishment of an acquired Specific Nerve energy, especially due to the varieties of nerve endings, and their common relation to special forms of stimulus. Thus there are about 20,000 forms of endings in the auditory apparatus. Only one kind of ending has been discovered in the organ of smell, — but it is known that the fine network of endings extends broadly over the olfactory region, and experiment may yet show unsuspect- ed variety. As such endings condition the stimuli which reach the nerves through them, the nerves are supposed to become gradually adjusted to particular forms of movement, and to respond more readily to these. There is doubt as to the final form of the theory of Specific Energy, but it seems to be necessary to accept the general statements here given. Ladd, 301-2, 353-5, 52-55. Kirk, 616, 619. Bowne, 43-46. Lindner, 39-40. Lotze, Outlines, 6-8 and 22-25. Wundt, I, 313 sq, (difficulties, and p. 318, a possible solution). 6. It would seem to be still farther established that every impression produces, in addition to the sensation awakened through the specific ending, an additional im- pression due to ^^ the nature of the place excited. ^^ This is the theory of Local Signs, due to Lotze, and of great importance in the discussion of the idea of space. It is adduced here as bearing on varieties of sensation. To use his illustration, — Every impression of red, r, pro- duces on all parts of the retina, the same sensation of red- ness. But on the various parts, a, hy c, it produces also the impression a', V , c', — according to the place. 20 GEN'ERAL PSYCHOLOGY. The cerebral areas would then be excited peculiarly, in response to this peripheral stimulus. Lotze, Outlines, 51-55. Ladd, 396-400. This evident relation of the sensation to the degree and kind of stimulus, as is seen in its intensity and quality, has led to eilorts to establish a law for the relation of stimulus and sensation, and so to the effort to measure the time (Psychometry) and degree of these elementary mental states. We thus have the science of Psychophysics. Kant had objected that sensations could not- be measured, as they had but one dimension, — time. But it was answered that intensity, which is equivalent to quantity, furnishes a second. Herbart, with his mechani- cal and mathematical tendency, gave great attention to the effort to express psychical facts in mathematical formulae (Eibot, 33 sq.). Fechner, however, believing earnestly that the physical and psychical are but two sides of one and the same life, gave his energies for years to expressing the law of their relationship, which held, he believed, through the whole domain of the psychical life. (See the Introd. ch. to his Hauptpuncte). The aim was to measure sensation in terms of stimulus, — since, in the nature of things there could be no subjec- tive measurement. Weber was experimenting in Germany, while Fechner was thinking out his theory. He tells us that ^^ one morning in bed^^ he suddenly formulated it, and then found Weber^s experimental law ready to his hands. He saw that the proportion of the sensation to the stimulus, as it was increased, was not in arithmetical pro- gression. He asserted that the stimulus must increase in geometrical progression to produce increase of sensation in arithmetical. Or, as he expressed it in his formula, Y (the sensation) = K (a constant) X log. B (stimulus). That is, the sensation is related not to the absolute amount GENERAL PSYCHOLOGY. 21 of stimulus, but to the logarithm of it ; the stimulus is not in arithmetical, but in geometrical proportion to the sensation. Weber^s experiments came to about the same conclusion. We strive to ascertain the smallest perceptible increase of sensation, and note the amount of stimulus needed to pro- duce the increase. So by numerous experiments, it is claimed, we tell the amount of sensation in terms of stimulus. A simple form of experiment may be referred to. The hand is placed on the table and weights are gradually set on it. Add till the subject notes a difference in feeling. Many repetitions of the experiment will show that from -| to i additional is always needed to produce a change of feeling. Similar experiments for other senses will be found in the references, and accounts of more complicated experi- ments. The increase in case of sensations of hearing is about i, in case of light about tfo, in muscular pres- sure iV. G-ranting the value of the experiments within a small range, for they are admittedly vitiated in conditions of low and exalted sensibility, the question still arises as to the light they throw on psychical life. The stimulus is applied to bodily organs, and is trans- mitted through nerve fibres and centres. It is far more probable that the change in the proportion of stimu- lus is due to these physiological conditions than to any psychical facts or law. Though the necessary increase in stimulus is found to be " a constant,^^ the mind recognizes only a difference, and the external measure cannot be an exact expression of any mental fact. Where the measurement of stimulus is physical and that of sensation psychical there can be no 22 GEN-ERAL PSYCHOLOGY. certainty in the results. The ''personal equation " must largely enter into the experiment. We can only say of intensities that they are more or less. To express this in mathematical formulae on the basis of experiments on stimulus would seem to be impossible. The results, thus far, therefore, would not seem to have important bearings on Psychology. The objection that the new Science is materialistic is met by Fechner in the assertion that the whole material universe is a representation of a universal spiritual Being, but that it is not for Psychophysics to develop that (Hauptpuncte, p. 13). The reply is valid, whether one accepts Fechner^s Monistic position, or not. The tendency of some investigators to press psychical action into the compass of the law of the (;orrelation and convertability of forces, is however undoubted. Fechner, Hauptpuncte der Psychophysik (espec. Introd, ch.) Ladd, Pt. 2, c. 5. Ribot, Germ. Psych, of To-day, p 43, 134 sq. (good resume). Lotze, 16-20. Murray, 23-29. Bowne, c. 2. Bald- win, 106 sq. Spencer, Psych. 1 : 98 sq. (espec. 115-128). Lindner, 31-35. Ward (Mind, vol. I. — a criticism of Fechner). Jastrow (Mind, vol. II). Methods of Experiment espec. in Jastrow and Ribot. Ueberweff 2 : 322-3. cf. Sully, 113-4. Dewey, 52. Wundt — Phys. Psych, (in Ribot, also, where Zeller and others are also quoted). Note Bowne, p. 52, on what Fechner's law may give, negatively ! And cf. James' humorous paragraph 1 : 549, (he thinks Weber's law purely physiological). This investigation serves to bring out more fully the facts implied in the definition. In the simplest elements of mental life we have the psychical and physiological in closest relation, but not identified with one another, or even coalescing. They are correlative. Every sensation involves. 1. An external stimulus ; ge:n-eral psychology. 23 2. The contact of this with a nerve ending through a sensitive portion of the body ; 3. The conduct of the impression, or its resultant move- ment, to the central organ ; 4. The sensation. The first three steps are distinctly physical ; the fourth is psychical. The three may occur without the fourth. This is directly against every materialistic theory of the origin of psychical life. In addition to what has been said-, pp. 7 and 8, on the relations of Psychology to Physiology, it is to be noted here, as the revelation of the first step in the analysis of mental life, that the soul of man has another nature than his body, and than the physical world which acts upon it. Materialism assumes that the physical, the changes of matter, and the forces of nature, are causes of psychical life. That the relation is a close one, that they may be occasions of mental activity, has been already indicated, but the facts are entirely against a causal relation. From the nervous excitation to the elementary consciousness, from motion to sensation^ no path is discoverable, or think- able. Nor can we conceive how motion can cause the various particular sensations to which we are subject, — waves of air resulting now in sound, now in light, — red, blue, or violet. Materialism has no explanation to offer : it must at last assume that these different worlds are causally related. (Xo general argument against Materialism is here attempted : it is referred to only as it concerns the begin- nings of psychic life). Murray, 26. Lotze, 9. Dewey, 38 sq. Spencer, 1 : 158-161. Benedict, Pop. Sci. Mo., June, '85. Bascom, Compar. Psych., c. 1. Id., Sci. of Mind, 454, Bowne, 19 sq. Carpenter, c. 1. 24 GEN"ERAL PSYCHOLOGY. Classification of Sensations. The various sensations have been classified according to the mode of motion operating on the organism, as dynamic, etheric, chemical, or mechanical and chemi- cal, or gaseous, liquid, solid, thermal, electrical. It will be seen, however, that all these have reference rather to the special forms of sensibility, as shown in the special or- gans of sense. There are beside these, various sensations due to the general system, not to be classified with those given through any special sense. The former are given through organs whose direct function is to furnish us with knowledge ; the latter are produced through organs having other special offices, and which are only indirectly organs of sense. Hence the classification may be properly made according to these classes : I. General Sensations, such as arise in connection with muscles and viscera. II. Special Sensations, such as are produced through the organs of smell, taste, touch, hearing, and sight, and the special sensibility of the muscular system, the so-called muscular-sense. See discussions of plurality of special senses, and relations of all to touch, as discussed by Aristotle, Scaliger, and others, in Bowen's Hamilton. 367 sq. Kant divides into Vital and Organic (special) ; Bowne into Intel- lectual and Organic (general). Hill, 32-33, gives Muscular. Organic, Special. Murray, whom I follow here, 29-31. Lindner, 36 and 39. Dewey, 46-50 (as here, with discussion of Touch as fundamental sense). Kirk (Common and Special) 616. General Sensations. The movements which accompany all life, such as are due to the action of the digestive and respiratory organs, for example, in their normal states, and to a still greater degree in abnormal conditions, are productive of Sensa- tions. These are not distinctly localized, — and they have GElfERAL PSYCHOLOGY. 25 very slight relation to knowledge, but have a closer rela- tionship to feeling, and so to the whole emotional life. The importance of the general system to the psychic life is thus indirect, though incalculably great, since the con- ditions of mental power and healthfulness largely depend on the physical system. Murray, 60-1, 65-71. Lindner, 37-9. Dewey, 75-8. Perez, 35. Porter, 137. Bain, 120-152. The Sensations of the Temperature Sense ally themselves more closely with these general sensations than with the special, but the progress of investigation tends to show a relation to the latter, in that something akin to a special organ has been discovered. In addition to the general sensibility of any organism to heat and cold the human system is supplied with a kind of special organ for thermal sensibility. Goldscheider^s and others" experiments, as related by Ladd, seem to demonstrate that there are certain spots on the skin sensitive to heat, and certain others sensitive to cold, — and these are insensitive to other stimulus, to pressure or to pain. But these sensations are also very vague, and like those just referred to have small importance in the development of knowledge. Ladd, pp. 346-350 (and refs.). Perez, 37-8. Murray, 68. Donaldson (Mind, No. 39). Special Sensations. Taste. — The sensations of taste, though awakened through a special organ, are almost as vague as those of the general senses. Efforts have been made to classify them, but with little success. They are with difficulty distinguished from those of smell, ofttimes, — as in case of cinnamon, for example, which has no taste. They are 26 GEN"ERAL PSYCHOLOGY. confounded with sensations of relish, which are alimen- tary. These have very small importance to knowledge, are very indefinite and transient in nature, and with difficulty, if at all, recoverable. As Bain points out, the sense is a help in discriminating what is proper for food, and a source of enjoyment in con- nection with it. Classif. of Tastes, cf. Murray, 33 and ref. Murray, 32. Dewey, 61. Bain, 152 sq. Grant Allen, Pop. Sci. Mo., 26: 471 sq. Bernstein, Five Senses of Man, Pt. 4. Ladd, 311-15. The Organ, Kirk, Ladd. Smell. — Sensations of smell are also very vague and are easily confounded with those of taste, with pulmonary and alimentary sensations, and with those due to irritating substances, as snuff or pepper. The sense is useful in testing the purity of air, and has close relation to appetite, and is thus, like taste, related closely to the emotional life. It is much more developed, accordingly, in animals, as in the dog, and in the lower races of men, than in the civilized. Bain, 163 sq, Ladd, 308-11. Murray, 36-40. Dewey, 59-61. Baldwin, 86. The Organ, Kirk, 635 sq. Bernstein, pt. 4. Muscular Sense. Among the special senses must be ranked that which is the avenue of our sensations of tension and motion. Until recently this was treated as a part of touch, but it differs essentially from the purely tactile sense, and, as will be seen, underlies the larger amount of knowledge gained through the senses of touch aud sight, and much also that is gained through the sense of hearing. The right of this to a special place has been denied by some, as Terrier, and W. James, on the ground that such GEKEEAL PSYCHOLOGY. 27 ** a complex assemblage of impressions of different cate- gories^^ has no claim to a single name. But this ^'com- plex " is traceable to a single origin, and the muscular system is the organ employed. This system contains both voluntary and involuntary muscles, those controlled by the will, and those, as the heart, beyond its control. The voluntary muscles are the organ of this sense. There is still much discussion as to the precise source of these sensations in the organism. There are sensory nerve fibres imbedded in the muscles, and many find the explana- tion in these. Others deny the sufficiency of this explana- tion, and ascribe the sensation to " central feelings of in- nervation,^^ the stimulus of the brain itself, while others ascribe them to the interpretation of the feelings in the skin, due to motion, tension, &c. Experiment (Beaunis, Ladd, Baldwin, in ref^s below) seems to show that the third theory is unsupported by facts, and the nature of the sensations experienced wo aid seem to indicate truth in doth the other hypotheses. The motion would seem to imply a central stimulus, and the tension the action of the sensory fibres in the muscles themselves. Tension includes all feeling of weight, whether due to the organism or to an external body. Motion includes all experiences of effort, from the most indolent dawdling to the most vigorous exercise. Sir Wm. Hamilton calls this feeling due to volitional effort ^* the locomotive faculty^' and confines '^ muscular sense ^' to the passive feeling due to tension. (Bain's criticism of this, p. 116.) Although the direct knowledge gained through the sense is small, it furnishes the data, in connection with the other senses, of the most important knowledge, the idea of force, body, space, and time (so Bain). Its value in connection 28 GEN-ERAL PSYCHOLOGY. with all acquired skill is manifest. But the consideration of these points belongs under Perception. The difference of this sense from others in regard to the mode of stimulus should be noted. They are all passive : this is active. The important bearing of this fact on knowledge will be seen later. Ladd, 344 and 415. Sully, 134 sq. Baldwin, 88 sq. Murray, 62- 65. Bain, 91 sq (with valuable quotations from specialists). Porter, 136. Dewey, 56. Wundt, 1 : 372. Kirk, 591 (supposition that the cerebellum is the special organ of this sense). History of the dis- covery of the sense. Hamilton's Reid, p. 867. Bastian, Brain as Organ of Mind, app., Hall, Mind, Oct., '78. Janes, 52-4. Hopkins, Outline, 87. Touch. — We deal here with the purely tactile sensibility. Most of our so-called sensations of touch are involved with the muscular sense. This is true of sensations of pressure (not all : the pressure spots, below), and most probably of those of roughness, smoothness, stickiness, &c. Through the tactile sense proper we have sensations of contact. Kirk adds pain, but this is not a simple sensation, as it involves pressure, or other muscular movement. The organ is the skin, and the membranes lining the mouth, nostrils, &c. The nails, teeth, and hair, may be mentioned as instruments of the general organ. The pe- culiar sensibility is due to the so-called " pressure spots,'' corpuscles in the skin, similar to the temperature spots al- ready described, and connected by fibrils with the larger nerves. They are scattered over the various parts of the body, and differ among themselves in sensitiveness. They yield a definite sensation of their own. Unlike the simpler senses, as taste and smell, which are receptive only of sapid or oxydized bodies, this has the widest possible range, responding to air, water, solids, all that can exert pressure. It will be seen, therefore, that this sense must furnish the data for a far wider range of GENERAL PSYCHOLOGY. 29 knowledge, when nsed, at it always is, in connection with the muscular sense already described. And not only is it susceptible to a large variety of influences, but the sensa- tions are easily discriminated and localized. The acuteness of the sensibility varies in different parts of the organ. The tip of the tongue and of the fore finger are most sensitive, the middle of the back the least so. (See tables in Hill and Kirk.) The results were obtained by Weber, who experimented with a pair of compasses, and discovered the least distance within which one can discern both points. This is his ^'sensory circle. ^^ (Full account in Bain, 188-191). Bernstein, ef. I. Baldwin, 96-7. Murray, 40-6. Sully, 123-5. Hill, 83-0. Porter, 143-7. Kirk, 620-7 and figures on 388 sq. Ladd, 346, 367 (Pressure spots). Bain, 175 sqq. Dewey, 47-59. Hearing. — Sonorous vibrations are the physical anteced- ents of the sensation of hearing. The complicated organ which receives the impressions — the Ear, external and in- ternal, is fully described in text-books of Physiology, cf. Kirk, 640 sq. and 652 (figure), — and Ladd, 185 sq. It is not known how the different vibrations affect the nerves so differently. Some suppose that there is a differ- ent nerve filament for every audible pitch, the ear being a kind of keyboard ; others, that sounds differ in pitch according to the length of the vibrations, — which, how- ever, is rather an hypothesis in physics than in neurology. The sensations are noises and musical sounds. Ladd • quotes Hensen as dividing the former into '' beats, or pulsations, Avhich disturb the purity of musical tones,' ^'^ the crackle, crash, or crack,'' and ^'hissing sounds." These, in combination with various musical sounds " make up the noises which we hear." Musical sensations differ in strength, or intensity, accord- ing to the breadth of vibrations, in pitch, according to 30 GENERAL PSYCHOLOGY. 