Before a life-work such as that of Emanuel Swedenborg one cannot but be filled with admiration. Perhaps not so much on account of the manysidedness of it; for that was not so very unusual at the time in which Swedenborg lived—in the 18th century;[12] but because his researches were at the same time so comprehensive and penetrating, because he made such great and important conquests within the most different departments of knowledge; indeed, in many places discovered by his sharpsighted genius the lines of development along which science was to proceed for the gaining of its end.

SWEDENBORG’S MATHEMATICAL, MECHANICAL AND ASTRONOMICAL INVESTIGATIONS.

Mathematics, especially geometry, algebra and mechanics, and astronomy in particular, were the predominating interests with Swedenborg, when, after having completed his university studies, he entered upon his first foreign journey (1710). He had at that time the good fortune to come into personal contact with (Isaac Newton?),[13] John Flamsteed[14] and Edmund Halley[15] in England, and with the renowned mathematicians Philippe de la Hire and Pierre Varrignon[16] in France, and to enter into an interchange of scientific ideas with them. And the impulses derived from teachers of such great insight and skill did not take long in manifesting themselves. In 1714 Swedenborg was able to send home accounts of a great many mechanical inventions which he had made and the ›correctness of which he proved by mathematical and algebraical calculations.›[17] As examples of these discoveries may be mentioned his flying machine,[18] submarine boat, steam engine, mitrailleuse, sluice constructions, etc.[17] After his return to Sweden he found opportunities of putting into practice some of these projects, when (in 1716) he was appointed assessor extraordinary in the College of Mines and ordered to assist Chr. Polhem ›with the construction of his buildings and inventions›. But he was rich in ideas and quick-witted enough to be able, together with these official duties, to plan and set on foot the publication of a periodical devoted to natural science, ›Daedalus Hyperboreus›, the first scientific periodical in Sweden, and to furnish it abundantly (during the years 1716-1718) with valuable articles concerning new inventions, projects and problems for scientific investigations and experiments.[19] In the year 1718 he has completed a new method of reckoning with the number 8 as the base; and the following year he publishes a still better ›Proposal to divide our money and measures, so that the calculation would be easy and all fractions be abolished›, and this system is nothing less than the Decimal system![20] He also published during these years an ingenious method of determining the longitude by means of the moon, a problem upon which the learned had at that time been engaged for several years.[21]

Swedenborg thus succeeded in penetrating very deeply into the mathematical and mechanical sciences, and therefore at first it must arouse astonishment that he did not accept the professor’s chair in mathematics at Uppsala University when this was offered him. He wished for freedom to study in other departments also. And, as we shall see, he soon turned his interest in another direction, namely to geology.

However, it was also a characteristic in Swedenborg, worthy of admiration, that in spite of his deep penetration into the sciences and the bold ideas of his creative genius, he nevertheless strove, at the same time, to retain contact with practical life and there cause the results of his investigations to bear fruit. It was also this purpose which to a great extent influenced him not to accept the offered professorship in mathematics, which he feared would force him into a direction too theoretical. In this respect there were, as some of his biographers have shown, several points of similarity between Swedenborg and his patron, King Charles XII., namely, ›the unusual combination of the boldest imagination and a pronounced practical tendency›.[22] And as both were animated by the same ›burning inclination for all that is great in thought and deed›, and by the same love of the fatherland, therefore, when these two men found one another, there was an interesting cooperation. Professor Holmquist has given a very good description of this in his essay alluded to above, from which I shall here reproduce some extracts:

— — — ›But Swedenborg had also in the course of his conversation with Charles XII. advanced several new proposals which won, in part, the King’s approval. Swedenborg suggested the establishment of a company to promote the exportation of Swedish iron and tar (a suggestion later put into practice by the Iron Office), set forth his plan for an observatory in Uppsala and brought up for discussion the establishment of salt works in Sweden in order to help his country against the terrible dearth of salt during the war: all these ideas he also committed to writing in pamphlets: ’Om sättet för handelns och manufacturernas uphjelpande’, ’Memorial om Salt Siuderiers inrettning i Swerje’ and ’Om nyttan och nödvändigheten af ett Observatorii inrättande i Sverige’ (preserved in manuscript in the Diocesan Library of Linköping).[23] Of the ideas just mentioned, it was in the first place the one on salt boileries which claimed the King’s attention and which he commissioned Swedenborg to put into practice. It still remains, however, to mention the most remarkable of Swedenborg’s projects. Through Eric Benzelius he had come into possession of an old letter of Bishop Hans Brask, in which the idea of a water way from the western coast straight across Sweden is expressed. Swedenborg, inspired by this, laid before the King the suggestion for a canal from Göteborg through Lakes Vänern and Vättern to the Baltic, which aroused the King’s enthusiasm. Swedenborg was commissioned to investigate the possibilities for the realization of this gigantic undertaking. — — — Shortly after this we find him in Uddevalla investigating the possibility of establishing salt-works, in connection with which Swedenborg at once set out to construct salt-pans and other apparatus better than those in use in the defective old salt-works at Strömstad. — — — We afterwards find him again at Trollhättan, Vänern, Gullspång and Hjälmaren examining the situation for the canal and locks and finding ’all to be possible and not of such great expense as had been supposed’. Swedenborg had passed over to the modern idea of an inland canal through Hjälmaren and Mälaren directly to Stockholm.› With justice it may be said that here he gives the impression of a very sharpsighted and energetic engineer, who possessed the power of turning his thorough theoretical education to practical use.

It may thus be clearly perceived, from everything I have referred to above, how comprehensive and penetrating were the researches of Swedenborg in the mathematical (and especially the mechanical) branches of science, and what fruitful discoveries had been made by his searching eye.

SWEDENBORG’S GEOLOGICAL, MINERALOGICAL, CHEMICAL, PHYSICAL AND COSMOLOGICAL INVESTIGATIONS.

Swedenborg’s comprehensive interest now turned itself to new fields of work: to geology, mineralogy, chemistry, physics and finally to cosmology, without giving up his first subject, mathematics.

And he also now exhibited the same thoroughness as before, beginning with examinations, experiments and observations, partly original, but also collected from predecessors. For he says: ›It seems to me that an infinite mass of completed experiments is a good ground to build upon, to make the trouble and expense of others serve one’s end; that is to work with the head over that which others have worked over with the hands.› (See Holmquist, Op. cit. and the letter from Swedenborg to Eric Benzelius of May 2nd, 1720, in the edition of the Acad. of Sciences, I., p. 304).

The result of this period of labour Swedenborg embodied in a number of works, among which may especially be mentioned: ›On the Height of Water and the Strong Tides in the Primeval World. Proofs from Sweden.›[24] Swedenborg here furnishes proofs that our North, in olden times, lay for the most part under deep water. And he based his deductions on a great many researches and sharpsighted observations, and wherever it was possible he tested the correctness of his conclusions by means of experiments. This is the work which J. J. Berzelius, A. E. Nordenskiöld and A. G. Nathorst have praised so highly, and in some places it has been considered to be ›one of the most ingenious contributions to the history of geology›. Swedenborg also worked out during this period the great work: ›Miscellanea observata circa res naturales et praesertim circa mineralia, ignem et montium strata›, (printed in Leipzig 1722 and lately reprinted in the edition of Swedenborg’s scientific writings of the Royal Academy of Sciences, Vol. I., 1907, pp. 59-191), and finally the gigantic work: ›Opera philosophica et mineralia›, (published in Dresden and Leipzig, 1734, in three large folio volumes). The last work contains among other things Swedenborg’s cosmology, and it is here that he developes his famous nebular theory, which so closely reminds one of the theory worked out in later years by Kant and Laplace, that one strongly suspects that Swedenborg’s utterances, in one way or another, lie at the bottom of it. Concerning this work much has been written during recent years, and therefore it may be sufficient here only to refer to the statements made in regard to it by Professor S. Arrhenius in his introduction to the above-mentioned edition of Swedenborg’s writings, Vol. II., where he says: ›If we briefly summarize the ideas, which were first given expression to by Swedenborg, and afterwards, although usually in a much modified form,—consciously or unconsciously—taken up by other authors in cosmology, we find them to be the following:

During this period of his investigations Swedenborg enters into very deep speculations. He desires to grasp the innermost constitution of things, their causes and origin, and seeks to attain this end through a long process of analyses and by applying a geometrical explanation to the phenomena in the world of the senses. This method he employs in explaining the inner constitution of chemical bodies, and likewise the varieties of physical phenomena, etc. He thus comes at last to the—geometrical points: through the combination of these, in different ways, have all things of the universe originated in a mathematically definable manner; and the motion of these points is the all connecting, life-giving power.[25]

SWEDENBORG’S ANATOMICAL AND PHYSIOLOGICAL INVESTIGATIONS.

After Swedenborg had so thoroughly searched through and speculated upon inorganic nature, he turns himself to the organic. He breaks away from all other work, travels abroad, and throws himself with intense zeal into anatomical and physiological studies. These researches were, for the most part, carried on in the Netherlands, France, and especially in Italy, where he remained for nearly a year.

After five years he was ready with his first work in this field, the large, famous ›Œconomia Regni Animalis,› which was printed in Amsterdam, 1740-1741. It was then published in two large volumes; but that it was designed to be still larger, is evident, among other things, from Swedenborg’s own statement;[26] and furthermore, the Englishman J. J. G. Wilkinson published, in 1847, as a third volume, some annotations which he regarded as belonging to Swedenborg’s manuscript of the same work.[27]

The ›Œconomia Regni Animalis› is chiefly directed to a detailed analysis of the blood, the brain, and finally the soul. In this investigation Swedenborg directed his attention not only to the morphological and physiological aspects of the subject, but also to the embryology of the organs; and he penetrated so deeply into the very essence of development, that, as Professor J. A. Hammar (Uppsala) has pointed out, he succeeded in arriving at a conception on this point, which was considerably better than that of his times. As is well known, during the first part of the eighteenth century the idea was generally prevalent that, when the organism developed from the egg or sperm, it grew forth out of it, much like a flower developes out of the bud, or, in other words, that the different organs existed pre-formed in the egg or sperm and that development consisted only in an extension of its size. Swedenborg expressed himself very decidedly against this ›pre-formation theory›: The development consisted by no means merely in a growth or expansion of the germ, (›seminis extensio›), or of a prototype of the future creature existent in the germ, (›non ... aliqua realis effigies maximi in minimo, seu in aliquo primo typus futuri corporis, qui simpliciter expanditur.› See Œc. R. A. I., No. 249); but there was in the germ a certain formative substance or power, by means of which the various parts of the embryo were developed one after the other, organ after organ. ( ... singula membra successive, seu unum post alterum producuntur ... Œc. R. A. I., No. 247).

It will be seen that Swedenborg has here put forth essentially the same theory as was later presented by Caspar Friedrich Wolff in his well known ›Doctorsdissertation› of the year 1759, i. e., the so called theory of ›epigenesis›.

I shall here also discuss some of the results and conclusions, which Swedenborg arrived at in the ›Œconomia Regni Animalis›, concerning the brain and its function.

As is well known the general principles of the macroscopical anatomy of the brain were known long before Swedenborg’s days; and even its microscopical structure had, half a century before his time, begun to be studied by such men as Leeuwenhoek (1632-1723), Malphigi (1628-1694), and others. For example, it was not only known that the substance of the brain, upon incision, exhibits an outer, greyish layer, the cortex, and an inner, more pure white mass, the medullary substance; but the above-mentioned investigators had also shown that the cortex of the brain consists of a numberless mass of small globular bodies, which are closely surrounded by blood-vessels and are continued in small thread-like extensions, which run into the medullary substance.[28] Now Swedenborg succeeded, as regards these globular bodies, in arriving at the conception that they are the most important components of the cortex and that it is in these bodies that the nerves originate.[29] He called them ›Sphaerulae› or ›Cerebellula›.

Again, as regards the medullary substance, it was already known through the works of Willis (1622-1675), Vieussens (1641-1716), Boerhaave (1668-1738), that it consists, for the most part, of a great mass of finer and coarser nerve-fibres, and that these, through the medulla oblongata,[30] continue down into the spinal cord, and that through the nerves they are in communication with the various parts of the body. The nerves were supposed to contain a lumen, thus being tubular. On the basis of certain clinical experiences concerning the changes which occur in the functions of the soul, when the cortex of the brain is injured, Swedenborg succeeded in drawing the conclusion that the same medullary fibres which are derived from the ›Cerebellula› of the cortex of the brain, continue into the spinal cord and are in connection with the nerves, and that thus an easily transmitted and continuous communication is established between the substance of the cerebral cortex and all the parts of the body, where the nerves are distributed.[31]

Concerning the function of the brain, the old view of Hippocrates that the brain was a gland was still entertained in Swedenborg’s time. The cortical substance served for secreting the ›spiritus animalis›, that is, what the ancients called the ›spirits of life›, and these were collected in the cortex of the brain that they might, when necessary, stream out through the nerves. The medullary substance was, according to the latest conceptions of that day, the origin and source of the soul’s activity, and the ›spiritus animalis› served as the connecting link between the soul and the sense-organs and muscles of the body.

Swedenborg also supposed that such a very easily flowing nervous fluid, ›fluidum spirituosum›, communicated the impressions of the senses and the impulses of motion: but this fluid determined the connection between sense-organs and muscles on the one hand, and the cortex of the brain on the other. It was thus the cerebral cortex! to which the impressions of the senses were carried, and from this the voluntary impulses were sent out to the muscles. The cortex was thus the seat of both the sensory and motor activities of the soul in the body. Œc. R. A. III., No. 133: ›Substantia enim corticalis est ipsum cerebrum, seu sensorium et motorium commune.›[32]

But Swedenborg was not contented with this general idea of the cortex as the seat of the sensations and the will. He also drew conclusions from his previous experience and results regarding the continuous connection between the elements of the cortex and the ends of the nerves distributed in the various parts of the body.

On the basis of this connection he ascribed to the ›Cerebellula› a very important rôle in the activity of the brain. In the first place they received, through the external sense-organs and nerves, impressions from the outer world and worked them over: they were a kind of inner sense-organs.[33] And since the sensory impressions were so richly various as well in kind as in degree, the ›Cerebellula› must also possess various individual qualifications corresponding to these various sensory impressions. They were, at the same time, connected with one another, and so arranged into superior and inferior groups that they could receive and work over the various kinds of sensory impressions.[34]

There were also other groups of grey substance in the interiors of the brain, through which the sensory nerves passed; but all sensory impressions must ultimately be gathered together in the cortex of the brain so as to become conscious perceptions.

(Thus, for example, Swedenborg describes the optic thalami as such a secondary centre in the course of the path of sight;[35] and the corpora striata in the path of the sense of smell;[36] and the origin of conscious tactile sensations he describes thus: — — — ›rudior quicunque tactus a superficie totius per medios nervos in Medullam Spinalem aut Oblongatam et abinde in activissimum cinerem, et in circumfusum corticem Cerebri emicet: Adeo ut extremi receptus modorum sint in cortice Cerebri, qui conscius redditur mutationum in seriebus et substantiis compositis usquam contingentium.› Œc. R. A. II., 192).

Thus: although Swedenborg did not suppose the ›Cerebellula› to be arranged into sensory centres in the same manner as we do, still he seems to have supposed an arrangement something resembling this, with Cerebellula-groups as subdivisions of the great sensible centre-organ, which is formed by the ›Cerebellula› of the brain cortex, taken together, and which Swedenborg called ›Sensorium commune.›

In regard to the relation of the cortex to motility, Swedenborg expresses himself much more definitely. This activity of the brain Swedenborg also regarded as derived from the small cortical elements, the ›Sphaerulae› or ›Cerebellula›.[37] He ascribes to them, on the one hand, a high degree of self-determination, so that they could perform their functions independently of each other, this on the basis of certain anatomical conditions, such as their position in respect to each other in separate cavities, and their connection each with its own special nerve-fibre, and, besides, also on the basis of certain clinical and pathological observations;[38] but on account of other anatomical conditions, such as the aggregation of the ›Cerebellula› into larger and smaller groups, as into gyres, and groups of gyres, etc., as well as on certain other grounds, he ascribed to them also the ability to cooperate with each other when necessary.[39] In consequence of this the brain possesses, as he says, the power and choice of influencing whatever nerves and muscles it will, and of stimulating them to activity. (›Proinde Cerebri secundum ordinatam ejus substantiae dispositionem in potentia et arbitrio est, quascunque velit fibras, aut fibrarum fasciculos, et consequenter nervos et musculos inspirare et ad agendum excitare.› Œc. R. A. II., 153). It was impossible for him to express himself as to what parts of the cerebrum or which convolutions, gyri, correspond to the respective muscles, but he refers to experimental investigations of animals, by which this might be discovered.[40]

But although the brain would then be able to govern every muscular action, it was not employed every time such an action was to be performed. No, in the medulla oblongata and in the grey substance of the spinal cord there were subordinate, secondary motor centres, and these governed the automatic and habitual movements, so that, for the performance of these, the brain need not be disturbed in its higher functions. Only for the purely voluntary motions were impulses from the cerebrum necessary.[41]

Swedenborg has thus clearly located the ›causa principalis› of the voluntary movements in the cortex of the cerebrum, or more definitely, in the cortical elements and in groups of such elements, although in this work ›Œconomia Regni Animalis› he did not succeed in more closely defining the position of the various motor centres.

From all that I have here brought forward concerning the functions which Swedenborg ascribes to the cortical substance of the brain, it is evident that he succeeded in coming to the full conviction that it is through the activity of the ›Cerebellula› (or as we express it, through the cerebral nerve-cells) that the perception of sense-impressions and the impulses to voluntary motions arise.

But Swedenborg does not stop even here. The elements of the cerebral cortex, he continues, are still not the ultimate determinants. They are only, so to speak, the inner sense-organs[42] and sub-determining media.[43] They are themselves subordinated under the understanding and the will, and their principle, the soul.[44] The soul, the principle of life, it is the soul, which, through those cortical elements, perceives the external world: it is the soul which feels, sees, hears, smells, tastes, it is the soul which recollects, thinks, performs, and wills; it is the soul which speaks and acts.[45]

What then is the soul, and where does she reside?

The seat of the soul must surely lie in the cerebral cortex; at least its activity comes into play there, and still more definitely, in the ›Cerebellula› of the cortex. (See above and also ›The Brain›, No. 7). But what is she? What is the soul?

Here Swedenborg makes one attempt after the other to draw away the obscuring veil. Sometimes he thinks of the soul as only dwelling and working in the ›Cerebellula› and their ›fluidum spirituosum›; but in this way he does not come to a solution of the principal question, which is only removed farther away.[46] Sometimes he thinks the soul to be identical with the ›fluidum spirituosum›; but how can this, however subtile fluid, be immortal? Here he is again repulsed.[47] He discusses the supposition that, although the ›fluidum spirituosum› in itself is not immortal, it yet becomes so upon the death of the body, and so forth.[48] And at last he bursts out with: ›it amounts to the same thing if we see in this fluid the soul itself, or only its faculty of imagination and judgment, for the one cannot be thought of without the other.›[49]

Swedenborg himself, however, was not satisfied with the result, but acknowledges that he had been too hasty, when, after having in reality thoroughly considered only the blood and brain, he entered immediately upon the search for the soul. He therefore says in the preface to the next work: ›I am now determined to allow myself no respite, until I have run through the whole field to the very goal—until I have traversed the universal animal kingdom to the soul (usque ad animam). Thus I hope, that by bending my course inward continually, I shall open all the doors that lead to her, and at length contemplate the soul herself: by the divine permission.›

It is grand to see the indomitable energy and zeal for investigation in this man of 53 years!

He was now obliged to extend considerably the field of his investigations—thereby to come to still more thorough insight into the conditions of the soul’s life, and afterwards, as he says, ›in his analytical way to be able to work himself up from the lower to the higher›, to find the way from phenomena and facts to causes and the final principles of the organism’s intricate mechanism.

Three years later he has ready the first two volumes of his new work, and the following year, 1745, a third volume. This work is the ›Regnum Animale›, (The Soul’s Kingdom). It is constructed upon a very grand plan, comprising not less than 17 parts. Of these, however, only the three mentioned above issued from the press, and they treat of the organs of the chest, abdomen, and skin, and of the senses of touch and taste.[50] Professor Immanuel Tafel (Tübingen) in the middle of the 19th century afterwards published two more volumes of the manuscript. The first of these, Pars quarta, treats chiefly of the senses of smell, hearing and sight and the higher degrees of the soul’s activity; and the other, Pars septima, treats of the soul.[50 b]

But simultaneously with the work in question Swedenborg wrote still another, namely, the great work on the brain, ›De Cerebro›.—In these works Swedenborg reached the summit of his scientific career, and they afterwards served as the foundation of the religious edifice to which he devoted the remainder of his life.

The ›De Cerebro› of Swedenborg, just referred to, is a rather large work which treats of the brain from the anatomical, physiological, and philosophical standpoints. This work left by Swedenborg in Ms., has appeared in print only in part, namely, in the English translation by Dr. Rudolf Tafel, published in London in two volumes, 1882 and 1887, and entitled ›The Brain›. Although this edition comprises, as was said, only a portion of the whole work, it treats of both the cerebrum, cerebellum and medulla oblongata, as well as of the cranium and the membranes of the brain, but chiefly only in so far as their structure and function regard the activity of the soul. Without doubt Swedenborg’s main interest here centred on this subject, and therefore I shall give some intimations concerning how deeply Swedenborg has succeeded in seeing into the function of the cerebrum as the organ of the soul’s life.

Swedenborg divided each hemisphere of the brain into an anterior and a posterior region, separated from one another by the fissure of Sylvius. Now, in the anterior region he located the essential activity of the soul, while as regards the posterior region, he supposed that it was chiefly active in animating the blood (›The Brain›, No. 71). In the anterior region he furthermore distinguished three lobes, or, as he called them, ›curiae›, in which the soul resided and exercised its functions (›The Brain›, No. 88). He does not define the boundaries of the lobes, but distinguishes them by saying that the soul’s activity in the highest lobe attains to the highest degree of clarity and perfection, while in the inferior lobes, the middle and the lowest, the soul’s activity successively decreases in sharpness and intensity! (›The Brain›, Nos. 66, 88). In these lobes or curiae the essential psychic life also has its rise; here observations, thoughts, judgments, conclusions come into being, yea, even determinations and the utterances of the will proceed thence. Here consequently is the source of both the sensory and the motor functions of the soul (›The Brain›, Nos. 88, 100).

As we have seen, Swedenborg had already shown, in ›Œconomia Regni Animalis›, not only that it is in the cortex, but just in the cortical elements, the ›Cerebellula›, that the brain’s psychic function is performed. Swedenborg emphasizes the same idea in ›De Cerebro›, and declares that these ›Cerebellula› are the units of which the brain is constructed, and from which its essential nature is derived (›The Brain›, No. 34).

As in the ›Œconomia Regni Animalis›, so in ›De Cerebro›, he also refers to the arrangement into different groups, which is so important for the function of the cortical elements or ›Cerebellula›, and with respect to this he now makes a new statement, which is of such a nature as necessarily to excite amazement: he sets forth the most essential part of the modern theory of localizations. Word for word this statement reads as follows: ›The muscles and actions which are in the ultimates of the body, or the soles of the feet, seem to depend more immediately upon the highest parts (of the anterior region of the brain)[51], the muscles which belong to the abdomen and thorax upon the middle lobe, those which belong to the face and head upon the third lobe; for they (the muscles of the body and the lobes of the brain)[51] seem to correspond to one another in inverse order›. (See ›The Brain›, No. 68).—Thus, the essential features of the modern doctrine concerning the relative positions of the motor centres in the cortex of the brain, that doctrine into which we have obtained an insight first after much comprehensive and complicated labour during the last century!

I shall no longer at this point continue the discussion of this work. What I have brought forward may suffice to indicate the character of Swedenborg’s investigation and the statements and discoveries based thereon. By his works on the brain Swedenborg reached the summit of his Scientific activity, but also its conclusion. He now passes over to the transcendental field. With the limits which we have set for our examination, we must, however, refrain from following the energetic investigator in his continued search for truth.