MAURY ON SLEEP AND DREAMS. 365 



and thought. We think and speak, we see and hear, 

 breathe and walk, indifferent as to the nature of these 

 marvellous functions, or how their unceasing work is 

 carried on. And well it is for our happiness, and for 

 the integrity of the functions themselves, that it should 

 be so. The mere act of mental attention to any one 

 of them is enough to alter or disturb its natural action 

 a fact of supreme importance in human physiology. 

 All this is eminently true as regards the subject be- 

 fore us. An habitual indifference to the phenomena 

 of sleep is found as much among men of general in- 

 telligence as in the mass of the unthinking world. 

 Assembled in the morning round the breakfast-table, 

 we laugh and jest over tales of the dreams of the 

 night; not reflecting that these wild and entangled 

 vagaries illusions as to persons, time, and place are 

 part and parcel of that continuous personal identity 

 which at other times manifests itself in acts of reason, 

 discourse, and deliberate functions of the will. We 

 are jesting here upon things .which have perplexed the 

 philosophy of all ages. No less a problem than the 

 intimate nature of the human soul is concerned in 

 these phenomena. Where more than a fourth part of 

 life, even in its adult and healthiest stages, is passed in 

 sleeping and dreaming, these functions must be taken 

 as an integral and necessary part of our existence not 

 less natural than our waking acts, and associated with 

 them by various intermediate phenomena, to which we 

 shall presently allude. These phenomena, indeed, may 

 be said really to maintain that unity of the thinking 

 and conscious being which in other ways they seem so 



