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generations of the first-created sarcode have descended to us unchanged from the period of the Laurentian limestone, other sarcodal offspring have developed and improved, or have been selected, into all higher forms of living beings. I prefer, however, while indulging in such speculations, to consider the various daily nomogeneously developed forms of protozoal or protistal jellies, sarcodes and single-celled organisms, to have been as many roots from which the higher grades have ramified, than that the origin of the whole organic creation is to be referred, as the Egyptian priests did that of the universe, to a single egg
Amber or steel when magnetized seem to exercise selection;' they do not attract all substances alike. To the suitable ones at due distance they tend to move; but, through density of constitution, cannot outstretch thereto ; so they draw the attracted’ substance to themselves. If the amber be not rubbed, or the steel bar otherwise magnetized, they are dead' to such power. The movement of a free body to a magnet has always excited interest, often wonder, from its analogy to the self-motion so common and apparently peculiar to life.'
A speck of protogenal jelly or of sarcode, if alive shows analogous relations to certain substances ; but the soft yielding tissue allows the part next the attractive matter to move thereto, and then by retraction to draw such matter into the sarcodal mass, which overspreads, dissolves, and assimilates it. We say that the Protogenes or Amoeba has extended a 'pseudopod, has seized its prey, has drawn it in, swallowed, and digested it. No organs, however, are recognizable ; neither muscle, mouth, nor stomach.
If the portion of iron attracted by the magnet became blended with the substance of its attractor, the analogy thereto of the act of the amæba would be, perhaps, closer, more just, than that other analogy which is expressed by terms borrowed from the procedure of higher organisms,
From certain knowledge of the homogeneous, by some termed 'unorganized,' texture of Protogenes and Amæba, we cannot predicate of their having sensation or exercising volition. Given life' and suitable organic substance at due distances, the act of making contact seems as inevitable, as independent of any volition of the amæba, as in the case of amber or steel, given 'magnetization' and attractable substances at due distance.
The term living,' in the one case, is correlative with the term 'magnetic' in the other. Devitalize the sarcode, un
magnetize the steel, and both cease to manifest their respective vital or magnetic phenomena. In that respect both are defunct.' Only the steel resists much longer the surrounding decomposing agencies.
A man perceives a ripe fruit: if he can and will, he stretches out his hand, plucks, brings to his mouth, masticates, swallows, and digests it.
The question then arises whether the difference between such series of actions in the man and the attractive and assimilative movements of the amæba, be less or greater, than the difference between these acts of the amaba and the attracting and retaining acts of the magnet.
More may be said on both questions than I have here space for ; but when all is said, the question, I think, may be put with some confidence as to the quality of the ultimate reply and the affinity to truth, and liberty to accept it, in the equal respondent, viz: whether the amæbal phenomena are so much more different, or so essentially different, from the magnetic phenomena than they are from the mammalian phenomena, as to necessitate the invocation of a special miracle for their manifestation,
Magnetic phenomena are sufficiently wonderful, exemplifying, as they do, one of those subtle, interchangeable, may we not say 'immaterial,' modes of force which endows the metal with the power of attracting, selecting, and making to move, a substance extraneous to itself. It is analogically conceivable that the same CAUSE which has endowed His world with power convertible into magnetic, electric, thermotic and other forms or modes of force, has also added the conditions of conversion into the vital mode.
Nerve-force we know to be convertible into electric energy, and reciprocally: and from the electric force, so induced, magnetic and other modes have been derived (vol. i, p. 357). The direction, then, in which may be anticipated the replies to the ultimate question, will be toward an admission of the originating and vitalizing of the primary jelly-speck or sarcode granule, by the operation of a change of force forming part of the constitution of Kosmos ; not contrary to its ordained laws, in the sense in which ‘miracle' or the interposition of special creative act,' is rightly understood.
But from protozoa,* or protista, to plants and animals, the gradation is closer than from magnetized iron to vitalized sarcode. From reflex acts of the nervous system, animals rise to sentient and volitional ones.
* This is the better as well as older term : Gãov being understood as 'life' generically, and before development has differentiated its manifestations into unam. biguous vegetal' and animal modes.
And with that ascent are associated brain-centers, progressively increasing in size and complexity. Arrest the development of the human brain at the point it has reached in the "Aztec,' and the faculty of generalizing and giving expression to such generalizations is wanting. The Aztecs can articulate words, and apply the right noun to the thing, as e. gbread,
chair ;' but they cannot combine ideas into propositions, and say 'give me bread,' set me the chair.'
For such advance in intellectual acts more brain is essential. Compared with the normal state of brains in the brutes best endowed, so much more cerebral substance is required, and in such position, as to make the great and sudden rise, in the lowest grades of man, which is referred to in vol. iii, p. 144.
Thought relates to the brain' of man, as does electricity to the nervous' battery of the torpedo : both are forms of force, and the results of action of their respective organs.
Each sensation affects a cerebral fiber, and in so affecting it, gives it the faculty of repeating the action, wherein memory consists, and sensation in a dream.
A dog at the sight of a rabbit receives a sensation which induces a volition, and he barks with the excitement of the chase. He sleeps, and by suppressed barking and agitation of limbs reveals the fact that he dreams. Shall we obtain any further insight into the nature of the act or acts resulting in this sensation, memory, dreamy imagination, by saying that the perception of the rabbit reaches the soul of the dog by the affection of its cerebral fibers ? Is the 'soul' of the dog other than the personified sum of his psychological manifestations ?
The sight of the dog, is its faculty of vision, the soul of a dog is its power of knowing what it sees and determining accordingly : it may approach the object with every manifestation of sentiments of gladness and submissive affection : it may rush upon it with every sign of rage : it may pursue it with every mark of excited ardor.
And these mental activities can only go on for a time: the waste thereby occasioned of fiber and of power calls for renovation, and this for repose, of the mental organ. In sleep the eyes close and sight goes ; what then happens to the brainfibers we cannot see nor tell : but the sum of action called
soul ceases. Deep sleep is utter unconsciousness to dog and man. The initial steps and partial resumptions of brain-action are dreams'; the awakening one issuing, often suddenly, in the full blaze of consciousness.
I am most averse to travel beyond my proper province; but a general physiological conclusion from the phenomena of the nervous system inevitably brings on collision with a dogmatic affirmation or definition of the cause of the highest class of those phenomena instilled as an article of religious faith into fellow-christians, and on which is based their mode of thought, affecting dearest hopes and highest aspirations. It must be repugnant to any good man's feelings to say aught that may unsettle such mode of thought, though he knows that what he has to impart lends truer and better support to both the faith and the hope.
If the hypothesis that an abstract entity produces psychological phenomena by playing upon the brain as a musician upon his instrument, producing bad music when the fibers or cords are out of tune, be rejected, and these phenomena be held to be the result of cerebral actions, an objection is made that the latter view is 'materialistic,' and adverse to the notion of an independent, indivisible, 'immaterial, mental principle, or soul.'
What materialistic' means, in the mind of the objector, I nowhere find intelligibly laid down ; but it is generally felt to be something objectionable, 'inconsistent with, or shaking the foundations of an article of faith,' as Stillingfleet would have said.
To this I repeat Locke's answer, that my faith in a future life and the resurrection of the dead, rests on the grounds of their being parts of a divine revelation.
If I mistake not, present knowledge of the way in which we derive ideas of an outer world, helps to a more intelligible conception of 'matter,' substance, immateriality,' &c., than could be framed by patristic and medieval theology. To make intelligible my own ideas in this subject, which the anticipated imputation draws from me, I would put a case and ask a question.
When Saul at Endor "perceived that it was Samuel,”* lines of force, as luminous undulations,' struck upon his retina. Qu. Were the centers whence they diverged to produce the idea of the dead Prophet 'material' or 'immaterial'?
Other lines of force, undulated in another manner, from centers producing the ideas of the dead man's speech : “Why hast thou disquieted me, to bring me up ?”† Qu. Were the centers radiating these acoustic lines of force material or spiritual ?
Substitute the living for the dead Prophet, and it will be said that the points whence the rays of light converged to produce his image in the beholder are 'material,' because 'tangible ;' in the case of the spirit of Samuel,''not. Had Saul stretched forth his hand to grasp the vision, it would have met
* 1 Sam. xxviii, 14. + 1 Sam. xviii, 15.
no resistance. Let us, then, analyze the sensations from tangible lines of force. I stretch forth the sum of forces called 'hand,' and exercise part of them in a way and direction called
pressure, deriving the sense or idea of such act by my lines of force being opposed by other lines of force. To the extent to which my forces overcome the opposing forces, I have an idea of a something giving way; when my lines of force are overcome by the opposite lines of force, I have the idea of a hard or resisting surface. But all that I know, after ultimate analysis, is the meeting of opposite forces; of the centers respectively radiating such force I know nothing; and if I did or could know anything, I cannot conceive that I should get a clearer idea of 'touch, than as a relation of certain lines of force acting from centers, which may as well be immaterial' as material, for any intelligible notion I can frame of those verbal sounds.
If a blade of metal could move itself to and fro, in striving to cleave the space between excited electro-magnetic poles, and could tell us its sensations, they would be those of sawing its way through a substance like cheese ; but there is no visible impediment: nor, were luminous undulations to vibrate from the hindrance, as from the plane of force resisting the pressing finger, would the hindrance be less immaterial.' Similarly, if lines of thought-force were visible, the 'ghost would not on that account be more 'material.'
The ideas excited by the act of pressure are those of the 'exertion of force' and the resistance of force ;' if these ideas be analyzed they include those of the direction of force in lines from centers or points. Further than this, my mind, or thinking faculty, cannot go ; i. e., can have no clear ideas : I cannot feel that I know more about the matter by calling the
centers of force,' 'material atoms' or ' immaterial points, and am resigned to rest at a point beyond which Faraday* did not see his way.
Having evidence of the opposing force acting in lines from centers distinct from and outside of those volitional centers called 'ego,' the sensation is sufficient for my belief that it is due to the reaction of lines of force from outside-centers upon lines of force put into action from inside-centers. But I have no ground for calling the one 'material and the other “immaterial,' or either, or both. The same result has followed my attempts to analyze all sensations and volitions, i. e., I know of nothing outside myself of which I can have any clearer knowledge by calling it material,' than I have of that which
* CCCXXXVII'', AM. JOUR. SCI.-SECOND SERIES, VOL. XLVII, No. 139.-Jan., 1869.