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the mystery of life never fails to suggest. Development and 
evolution have become terms convenient for the enchanter or 
juggler to conjure with in the haunted caves of metaphysical 
subtlety ; and it would seem at times as though, whether it 
be enchantment or jugglery, the first victim of either is usually 
the operator himself. 
The writers who have most effectually contributed to the 
maturity and exposition of this system are, Mill the father 
and Mill the son, Alexander Bain, John Tyndall, Thomas H. 
Huxley, Charles Darwin, Herbert Spencer, George H. Lewes, 
and John Fiske. 
Besides these we ought not to overlook the crowd of 
naturalists, both the solid and romantic, who, having accepted 
the evidence for evolution within certain limits, are ready to 
extend it indefinitely over all regions of knowledge that are 
unfamiliar to themselves or in their nature not easily grasped, 
and are content to make it the substitute for the absolute, the 
infinite, and the living God. Were we to assign to each of 
these writers we have named the element which he has con- 
tributed to this new metaphysics and the agency which he 
excited, we must needs write a careful criticism and a philo- 
sophical history of the theories of each of these eminent men. 
It will be enough to say that James Milks bald and yet half- 
digested sensationalism ; John Stuart Milks exposition of 
induction, his Comtian theory of causality, together with his 
necessitarian and sociological ethics, and his doctrine of asso- 
ciationalisin as contained in his criticism of Hamilton; Alexander 
Banks gross physiological cerebralism, and his thorough-paced 
associationalism, in which he surpasses even Stuart Mill him- 
self; Thomas H. Huxley's doctrine of protoplasm as the 
physical basis of life ; Michael Faraday's brilliant suggestion 
of the correlation of force, confirmed by numerous experiments 
on the part of careful followers, which has been so brilliantly 
expounded and so daringly applied by the eloquent John 
Tyndall ; Charles Darwin's doctrine of the origination of 
species by the law of natural selection under the conditions 
of a favourable or hostile environment, and his doctrine of 
heredity as subsequently enounced; Herschel and Laplace's 
nebular hypothesis ; the Kantian doctrine of the relativity of 
knowledge as interpreted by Hamilton and applied by Mansel 
— were all more or less distinctly before Mr. Herbert Spencer 
when he matured the romantic generalization by which he 
explains the generation of the universe of beings — mechanical, 
physical, spiritual — under the formula of development or evo- 
lution, and assumed for it a steady and continuous progress 
from the simple to the complex, attended by a constant ten- 
