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.Spencer's argument implies that eachorder of cells transmits just as many impulses as it receives to the cells above it; so that if theblows come at the rate of 20,000 in a second the cortical cells discharge at the same rate, and oneunit of feeling corresponds to each one of the 20,000 discharges.Then, and only then, does'integration' occur, by the 20,000 units of feeling 'compounding with themselves' into the'continuous state of consciousness' represented by the short line at the top of the figure.Now such an interpretation as this flies in the face of physical analogy, no less than of logicalintelligibility.Consider physical analogy first.A pendulum may be deflected by a single blow, and swing back.Will it swing back the moreoften the more we multiply the blows? No; for it they rain upon the pendulum too fast, it will notswing at all but remain deflected in a sensibly stationary state.In other words, increasing thecause numerically need not equally increase numerically the effect.Blow through a tube: you geta certain musical note; and increasing the blowing increases for a certain time the loudness of thenote.Will this be true indefinitely? No; for when a certain force is reached, the note, instead ofgrowing louder, suddenly disappears and is replaced by its higher octave.Turn on the gasslightly and light it: you get a tiny flame.Turn on more gas, and the breadth of the flameincreases.Will this relation increase indefinitely? No, again; for at a certain moment up shootsthe flame into a ragged streamer and begins to hiss.Send slowly [p.156] through the nerve of afrog's gastrocnemius muscle a succession of galvanic shocks: you get a succession of twitches.Increasing the number of shocks does not increase the twitching; on the contrary, it stops it, andwe have the muscle in the apparently stationary state of contraction called tetanus.This last factis the true analogue of what must happen between the nerve-cell and the sensory fibre.It iscertain that cells are more inert than fibres, and that rapid vibrations in the latter can only arouserelatively simple processes or states in the former.The higher cells may have even a slower rateof explosion than the lower, and so the twenty thousand supposed blows of the outer air may be'integrated' in the cortex into a very small number of cell-dischargesin a second.This other diagram will serve to contrast this supposition withSpencer's.In Fig.26 all 'integration' occurs below the threshold ofconsciousness.The frequency of cell-events becomes more andmore reduced as we approach the cells to which feeling is mostdirectly attached, until at last we come to a condition of thingssymbolized by the larger ellipse, which may be taken to stand forsome rather massive and slow process of tension and discharge inthe cortical centres, to which, as a whole, the feeling of musical tonesymbolized by the line at the top of the diagram simply and totallycorresponds.It is as if a long file of men were to start one after the other to reach a distant point.The road at first is good and they keep their original distance apart.Presently it is intersected byGet any book for free on: www.Abika.com THE PRINCIPLES OF PSYCHOLOGY97bogs each worse than the last, so that the front men get so retarded that the hinder ones catch upwith them before the journey is done, and all arrive together at the goal.[11][p.157] On this supposition there are no unperceived units of mind-stuff preceding andcomposing the full consciousness.The latter is itself an immediate psychic fact and bears animmediate relation to the neural state which is its unconditional accompaniment.Did each neuralshock give rise to its own psychic shock, and the psychic shocks then combine, it would beimpossible to understand why severing one part of the central nervous system from anothershould break up the integrity of the consciousness.The cut has nothing to do with the psychicworld.The atoms of mind-stuff ought to float off from the nerve-matter on either side of it, andcome together over it and fuse, just as well as if it had not been made.We know, however, thatthey do not; that severance of the paths of conduction between a man's left auditory centre oroptical centre and the rest of his cortex will sever all communication between the words whichhe hears or sees written and the rest of his ideas
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