June 30, 18S1] 



NATURE 



believe that he is enjoying it ; or that of a conceited man 

 who thinks more highly of himself than a just introspec- 

 tion, untainted by emotion, would show that he de- 

 serves. It is pointed out that illusions of introspection 

 have been more generally recognised by theologians 

 than by philosophers ; for while the former preach 

 that the heart mistakes the fictitious for the real, 

 and the evanescent for the 'abiding, the latter frequently 

 regard a " deliverance of consciousness " as bearing the 

 seal of supreme authority. This consideration leads to 

 an interesting section on "Philosophic Illusions," wherein 

 the question is discussed as to how far the introspective 

 method is a trustworthy one for Philosophy to follow. 

 The result of the discussion is that, as the internal expe- 

 rience of individuals, no less than their common environ- 

 ment, has a common nature, individual introspection 

 should always be guided as much as possible in matters 

 of internal experience by the general consensus ; and 

 that " the progress of psychology and the correction of 

 illusion proceed by means of an ever-improving e.xercise 

 of the introspective faculty." 



Coming next to the Illusions of Memory, or Represen- 

 tative as distinguished from Presentative Illusions, it is 

 shown that these are distinct from mere forgetfulness or 

 imperfection of memory. To forget a past event is one 

 thing ; to seem to ourselves to remember it when we 

 afterwards find that the event was other than we repre- 

 sented it, is another thing. Illusions of memory are classi- 

 fied under three heads :— (i) Falsification of Dates ; (2) 

 Misrepresentation of Events j and {2,) Creation if Events 

 by the Imagination which never happened in Reality. 

 Each of these classes of illusory representations has its 

 counterpart in the illusions of Presentation. Thus, 

 Class I has its visual counterpart in erroneous percep- 

 tions of distance ; Class 2 in those optical illusions which 

 depend on the effect of haziness or the action of refract- 

 ing media ; and Class 3 in subjective sensations of light 

 or other hallucinations. In the detailed discussion of 

 Class I there is a long and careful analysis of time- 

 consciousness, in which numerous causes of erroneous 

 estimate of duration are clearly stated, after which fol. 

 lows a statement of the conditions leading to Indefinite 

 Localisation ; these sections are exceedingly good. Under 

 Class 2, or Distortions of Memory, it is shown that 

 although we may in some cases account for the confusion 

 of fact with imagination, " in other cases it is difficult to 

 see any close relation between the fact remembered and 

 the foreign element imported into it. An idea of memory 

 seems sometimes to lose its proper moorings, so to speak; 

 to drift about helplessly among other ideas, and finally, by 

 some chance, to hook itself on to one of these, as though 

 it naturally belonged to it." The analogy between this 

 class of mnemonic illusions and that of illusions of per- 

 ception is obvious. " When the imagination supplies the 

 interpretation at the very time, and the mind reads this 

 in to the perceived object, the error is one of perception. 

 When the addition is made afterwards, on reflecting upon 

 the perception, the error is one of memory." To the 

 several sources of such mnemonic illusions mentioned by 

 Mr. Sully, I may add another, which I have recently had 

 occasion to observe. This consists in what may be 

 called a transposition of associations. In a club I saw a 

 man walk through the smoking room. He was an 



eminent psychologist, and although I knew him very well 

 I mistook him for another man equally eminent in the 

 same line, and whom I knew equally well. Clearly the 

 similarity of their pursuits caused a most extraordinary 

 transposition of two sets of associations, for the two m.n 

 bore no personal resemblance to one another. As soon 

 as the man had left the room, I remembered that I had 

 something to ask the man for whom I had mistaken him. 

 I therefore sent a page to find this other member of the 

 club, but without success. I then went to the haU-poi ter 

 who said he was sure that this member had not come in. 

 Yet so strong was my conviction of having seen him 

 that I began to think I must have seen an optical illusion 

 and therefore resolved to write him a letter to ascertain 

 still more certainly that he had not been in the club at 

 that particular hour. And it was not until I had seriously 

 meditated on the matter for ten or twelve minutes that I 

 suddenly perceived the ilKision to have been one of 

 memory and not of sense. This I think is a remarkable 

 case, because both the men in question are so well know n 

 to me that I have never ventured to tell either of them of 

 my illusion, lest, psychologists though they be, they should 

 suppose that I had been somewhat excessive in patronis- 

 ing the good things which the club had to afford. 



It is shown that Hallucinations of Memory may arise 

 either from believing events in dreams to have occurred 

 in fact, or from waking imagination being strong enough 

 to read spurious facts into the past. The former source 

 is clearly common to us all, and the latter is so far from 

 being distinctive of pathological condition that in one 

 respect, at least, it is even more universally present than 

 the other. For " the total forgetfulness of any period or 

 stage of our past experience necessarily tends to a vague 

 kind of hallucination. In looking back on the past we 

 see no absolute gaps in the continuity of our conscious 

 life." Yet it is obvious that we must fill up immense 

 lacunje without conscious knowledge, and in so far as 

 this is the case, memory is subject to hallucination. From 

 thfs position there follows a section on " Illusions with 

 respect to Personal Identity," the substance of which may- 

 be gathered from the following quotation : — " To imagine 

 that we hare ourselves seen what we have only heard 

 from another or read, is clearly to confuse the boundaries 

 of our identity. And with respect to longer sections of 

 our history, it is plain that when we wrongly assimilate 

 our remote with our present self, and clothe our childish 

 nature with the feelings and the ideas of our adult life, 

 we identify ourselves over much. In this way, through 

 the corruption of our memory, a kind of sham memory 

 gets mixed up with the real self, so that we cannot, 

 strictly speaking, be sure that when we project a mne- 

 monic image into the remote past we are not really 

 running away from our true personality." 



Lastly, we come to " Illusions of Belief" the latter 

 word being taken in its widest sense as embracing all 

 representative knowledge other than memory — including 

 therefore anticipation of the future, acquaintance with the 

 experience of others, and " our general knowledge about 

 things." In so wide a field there is boundless scope for 

 illusions of many kinds. These are classified and con- 

 sidered in the latter part of the work, but we have no 

 space left to follow our diligent author into this division 

 of his subject. 



