icals. As early as 1842, in a series of letters to the
Nonconformist newspaper on "The Proper Sphere of Government," he
propounded a belief in human progress based on the modifiability of
human nature through adaptation to its social surroundings, and he
asserted the tendency of these social arrangements to assume of
themselves a condition of stable equilibrium. From 1848 to 1853 he was
sub-editor of the Economist newspaper, and in his first important work,
"Social Statics," published in 1850, he developed the ethical and
sociological ideas which had been set forth in his published letters.
The truth that all organic development is a change from a state of
homogeneity to a state of heterogeneity is regarded by Spencer as the
organizing principle of his subsequent beliefs. It was gradually
expounded and applied by him in a series of articles contributed to the
"North British," the "British Quarterly," the "Westminster," and other
reviews. In these essays, and especially in the volume of "Principles of
Psychology," published in 1855, the doctrine of Evolution began to take
definite form, and to be applied to various departments of inquiry. It
was not until four years later--a fact to be carefully borne in mind by
those who would estimate correctly the relation of Spencer to
Darwin--that the publication of the latter's "Origin of Species"
afforded a wide basis of scientific truth for what had hitherto been
matter of speculation, and demonstrated the important part played by
natural selection in the development of organisms. As early as March,
1860, Spencer issued a prospectus, in which he set forth the general aim
and scope of a series of works which were to be issued in periodical
parts, and would, collectively, constitute a system of philosophy. In
1862 appeared the "First Principles," and in 1867 the "Principles of
Biology." In 1872 the "Principles of Psychology" was published; the
first part of the "Principles of Ethics" in 1879; and his "Principles of
Sociology" in three volumes, begun in 1876, was completed in 1896. In
the preface to the third volume of the last-named work the author
explains that the fourth volume originally contemplated, which was to
deal with the linguistic, intellectual, moral, and aesthetic phenomena,
would have to remain unwritten by reason of the author's age and
infirmities. The astounding extent of Herbert Spencer's labors becomes,
indeed, the more marvellous when one considers that impaired h