The Way of Escape 155 
design, which underlies function, is the fittest idea with 
which to connect them in our minds. 
We will now proceed to inquire how Mr. Darwin came to 
substitute, or try to substitute, the survival of the luckiest 
fittest, for the survival of the most cunning fittest, as held 
by Erasmus Darwin and Lamarck ; or more briefly how 
he came to substitute luck for cunning. 
