XII 
THE HAZARDS OF THE PAST 
I 
ERGSON, the new French philosopher, thinks 
we all had a narrow escape, back in geologic 
time, of having our eggs spoiled before they were 
hatched, or, rather, rendered incapable of hatching 
by too thick a shell. This was owing to the voracity 
of the early organisms. As they became more and 
more mobile, they began to take on thick armors 
and breastplates and shells and calcareous skins to 
protect themselves from one another. This tend- 
ency resulted, he thinks, in the arrest of the en- 
tire animal world in its evolution toward higher 
and higher forms. These shells and armors begat 
a kind of torpor and immobility which has con- 
tinued down to our day with the echinoderms 
and mollusks, but the arthropods and vertebrates 
escaped it by some lucky stroke. Now you and 
I are here without imprisoning shells on our 
backs; but how or why did we escape? Bergson does 
not say. Was it a matter of luck or chance? Was 
there ever a time when the stream of life tended to 
harden and become fixed in its own forms like a 
stream of cooling lava, or has the innate plasticity 
225 
