CONSCIOUSNESS 213 



ness than was the philosopher. They possess, however, 

 the vantage of the evolutionary point, not available in 

 the eighteenth century, and are prepared to look upon 

 consciousness (as man knows it subjectively) as the very 

 complicated product of a very long process of evolution. 

 As the human vmderstanding surpasses that of the 

 ape, and that of the ape surpasses that of the fishes, so 

 in almost as extreme a degree the vertebrate brain sur- 

 passes the nervous organs of the invertebrates. A reason 

 for this diflPerence, one thinks, is to be found in history, 

 and in a very elementary biological fact. All animals are 

 dependent on either plants or animals for food, and from 

 its beginnings the evolution of the animal kingdom has 

 in the main presented a pageant of predator and prey- 

 eat or be eateni In the Cambrian period, which opened 

 some 550 milHon years ago, there may have been many 

 soft-bodied animals which are not preserved in the fossil 

 record, but most of those which are preserved possessed 

 destructive mouth parts, prehensile limbs and muscular 

 appendages by which they could pursue their prey, and 

 they were themselves protected from their enemies by 

 chitinous or calcareous exoskeletons. The mobile, preda- 

 tory habit (with obvious exceptions for scavengering, 

 vegetarianism and parasitism) early became what we 

 may call the typical habitus of the animal kingdom, and 

 this habitus required that the successful animal solve 

 the problem of two moving bodies— its own and that of 

 its prey— and not just in the three dimensions of space, 

 but in a fourth: accurate timing was a sine qua non, 

 and accurate timing required the integration of events of 

 the recent past with those of the present moment, thus 

 permitting extrapolation into the future and assuring 

 both food and safety. 



If we set to one side, as supported by insufficient evi- 

 dence, all such means of foreseeing the future as crystal 

 balls, palm reading, lot casting, astrology, hepatoscopy, 

 table tipping, and clairvoyance, the future can be antici- 



