Page:Mind (New Series) Volume 12.djvu/406

 392 CEITICAL NOTICES I to adopt Darwin's explanation of the tears being due to the con- traction of the muscles compressing the gorged ocular blood-vessels. From Prof. James's theory that the emotion of laughter is mainly consciousness of accomplished motor effects occasioned by the perception of the ludicrous Dr. Sully dissents ; but he allows that " though the bodily reverberation is not everything in an emotion it is an important part," and " the large expansion of the area of nervous commotion throughout the bodily system gives added life and a more distinctive character to the enjoyment of fun " (p. 44). This seems to me the true view, but I am under the impression that it is not widely different from Prof. James's later teaching on the subject, as he has, I understand, toned down his earlier ex- aggerated though useful insistence, on the constituent part which is undoubtedly played by the bodily sensations in all the more violent emotions. Passing on to the more elementary causes of laughter the author allots an interesting section of sixteen pages (pp. 50-66) to the subject of tickling. The reactions he holds, in agreement with Drs. Hill and Eobinson, are partly of a "defensive character," partly " expressive of enjoyment " (p. 56). The consciousness is complex and the conclusion of Prof. Sully's analysis is that " the laughter excited by tickling is not a net effect of the sensory stimulation," but its conditions also include " a higher psychical factor, namely, an apperceptive process or assignment of meaning to the sensa- tions," an inference borne out by the fact that the laughter-reaction occurs first of all (to give the earliest date) in the second month presumably in the " second half of this month " (p. 59). That the ''interpretation" is the decisive element in eliciting laughter may be tested by any reader who is conscious of a creepy-skin sensation by mentally ascribing it either to a parasite or to some properly ticklish cause (p. 60). I confess I am not convinced by this reason- ing. That the laughter caused by tickling is originally purely physical and reflex seems to me far more probable ; and the fact that the reaction in the infant can be evoked so early as the seventh week instead of establishing the psychical apperceptive link contended for by Prof. Sully seems to me to point the other way. Certain reflexes as well as instinctive actions require a ripening of the co- ordinating nerve-centres and when once this has taken place the appropriate motor reactions speedily exhibit themselves, as Prof. James has shown. That at a later age when associations have been consciously formed mental suggestion should either intensify or inhibit laughter which was originally the direct effect of phy- sical stimulations is explicable by the ordinary laws. We have in laughter, it seems to me, a good instance of "plurality of causes". The phenomenon may be the effect of a physical excitant, or of a rational perception, or of both combined. From this the author passes on to some judicious observations with respect to the manner in which joyous feeling in general conduces to laughter, the "play-attitude," the " teasing impulse,"