Introduction. XVII 
the intellectual atmosphere necessary for the serious 
adoption of beliefs such as these, which, in spite of their 
persistence in folklore, seem so puerile to us moderns. 
It was the time when the serious attention of mankind 
probably first became rivetted on the problems of the 
nature of life and death. The realisation of the fact that 
sometimes the bodies of the dead did not undergo a pro- 
cess of dissolution when buried seems to have given 
support to the vague longings for a continued existence 
after death, with which no doubt imagination may often 
have played before then, and set men thinking of the 
elements of which death had robbed the once living body. 
The outcome of these enquiries was the development of 
ritual procedures which aimed at restoring to the corpse 
the breath of life (by the ceremony of opening the mouth), 
the waters of life (by the offering of libations), and the 
odour and sweat of life (by the burning of incense). But 
for us in this enquiry, the more important result was the 
body of beliefs which grew up in association with these 
ritual observances as the definite formulation of a coherent 
system of primitive biological and psychological con- 
ceptions. 
The idea cf the heart and the blood as the vehicles 
of knowledge and the will was probably much older than 
this, and already had probably prompted such ceremonial 
procedures as the drawing of blood, whether by incision 
or circumcision, by ear-piercing or by skin-gashing, many 
centuries before the first real scientific attack upon the 
problems of vitalism, to which I have been referring ; but 
incidentally it helped to give more definite shape and 
precision to these early conceptions of the vascular system. 
So also the belief in the vitalising power of water was 
definitely more ancient ; for it came to be vaguely recog- 
nised as soon as the art of agriculture first was put into 
