NOTES ON GHOSTS AND GOBLINS. 429 



the imagination is more likely to conjure up pictures 

 connected with those thoughts than such random pic- 

 tures as are formed when the mind is not so preoccupied. 

 If we admit this and I can conceive that there can be 

 very little doubt on the point we can dispose very 

 readily of the argument from coincidence, advanced 

 by those who believe that the spirits of the dead some- 

 times come visibly into the presence of the living. I 

 present this argument as urged in an analogous case 

 (that of visions at the moment of death) by a late 

 eminent mathematician, whose belief in the possibility 

 at least of many things which are commonly regarded 

 as superstitions was so well known that no apology 

 need here be made for touching on the subject. After 

 speaking on the general subject of coincidences, De 

 Morgan thus, in language less simple than he com- 

 monly employs, presents the argument for spectral 

 apparitions (at the moment of the death of the person 

 so appearing): 'The great ghost-paradox and its 

 theory of coincidence will rise to the surface in the 

 mind of everyone. But the use of the word coinci- 

 dence is here at variance with its common meaning. 

 When A is constantly happening, and also B, the 

 occurrence of A and B at the same moment is the mere 

 coincidence which may be casualty.' (That is, this is 

 a coincidence of the common kind.) ( But the case 

 before us is that A is constantly happening ' (here by 

 A, De Morgan means a death, as he explains further 

 on, but the explanation should come in at this point) 

 e while B ' (the spectral appearance of the person who 



