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SCIENCE 



[N. S. Vol. XXXVIII. No. 974 



tion of all parts of the body leaves the 

 brain cells in a state of equilibrium. Our 

 theory of pain will then be well sustained, 

 not only by common observation, but by 

 experimental proof, and so the mechanistic 

 view will be found in complete harmony 

 with another important reaction. 



We have stated that when a number of 

 contact stimuli act simultaneously, the 

 strongest stimulus will gain possession of 

 the final common path — the path of action. 

 Wlien, however, stimuli of the distance cep- 

 tors compete with stimuli of the contact 

 ceptors, the contact-ceptor stimuli often 

 secure the common path, not because they 

 are stronger or more important, but be- 

 cause they are immediate and urgent. In 

 many instances, however, the distance-cep- 

 tor stimuli are strong, have the advantage 

 of a lowered threshold, and therefore com- 

 pete successfully with the immediate and 

 present stimuli of the contact ceptors. In 

 such cases we have the interesting phenom- 

 enon of physical injury without result- 

 ant pain or muscular response. The dis- 

 tance ceptor stimuli which may thus tri- 

 umph over even powerful contact-ceptor 

 stimuli are those causing strong emotions 

 ■ — as great anger in fighting; great fear in 

 a battle; intense sexual excitement. Dr. 

 Livingstone has testified to his complete un- 

 consciousness to pain during his struggle 

 with a lion; although he was torn by 

 teeth and claws, his fear overcame all 

 other impressions. By frequently repeated 

 stimulation the Dervish secures a low 

 threshokl to the emotions caused by the 

 thought of God or the devil and his emo- 

 tional excitement is increased by the pres- 

 ence of others under the same stimulation ; 

 emotion, therefore, secures the final common 

 path and he is unconscious of pain when he 

 lashes, cuts and bruises his body. The 

 phenomena of hysteria may be explained 

 on this basis, as may the unconsciousness 



of passing events in a person in the midst 

 of a great and overwhelming grief. By 

 constant practise the student may secure 

 the final common path for such impressions 

 as are derived from the stimuli offered by 

 the subject of his study, and so he will be 

 oblivious of his surroundings. Concentra- 

 tion is but another name for a final com- 

 mon path secured by the repetition and 

 summation of certain stimuli. 



If our premises are sustained then we 

 can recognize in man no will, no ego, no 

 possibility for spontaneous action, for 

 every action must be a response to the 

 stimuli of contact or distance ceptors, or 

 to their recall through associative memory. 

 Memory is awakened by symbols which 

 represent any of the objects or forces asso- 

 ciated with the act recalled. Spoken and 

 written words, pictures, sounds, may 

 stimulate the brain patterns formed by 

 previous stimulation of the distance cep- 

 tors; while touch, pain, temperature, pres- 

 sure, may recall previous contact-ceptor 

 stimuli. Memory depends in part upon 

 the adequacy of the symbol, and in part 

 upon the state of the threshold. If one has 

 ever been attacked by a snake, the thresh- 

 old to any symbol which could recall that 

 attack would be low; the later recall of 

 anything associated with the bite or its re- 

 sults would produce in memory a recapitu- 

 lation of the whole scene, while even harm- 

 less snakes would thereafter be greeted 

 with a shudder. On the other hand, in a 

 child the threshold is low to the desire for 

 the possession of any new and strange ob- 

 ject ; in a child, therefore, to whom a snake 

 is merely an unusual and fascinating ob- 

 ject, there is aroused only curiosity and the 

 desire for the possession of a new play- 

 thing. 



If we are to attribute to man the posses- 

 sion of a governing attribute, not possessed 

 by other parts of the animal creation, 



