Here the evolutionist struck the note of optimism.  And he suggested that laws of Progress would be found in other quarters than those where they had hitherto been sought.

The ablest and most influential development of the argument from evolution to Progress was the work of Spencer.  He extended the principle of evolution to sociology and ethics, and was the most conspicuous interpreter of it in an optimistic sense.  He had been an evolutionist long before Darwin’s decisive intervention, and in 1851 he had published his Social Statics, which, although he had not yet worked out the evolutionary laws which he began to formulate soon afterwards and was still a theist, exhibits the general trend of his optimistic philosophy.  Progress here appears as the basis of a theory of ethics.  The title indicates the influence of Comte, but the argument is sharply opposed to the spirit of Comte’s teaching, and sociology is treated in a new way. [Footnote:  Social Statics, or the Conditions Essential to Human Happiness specified, and the first of them developed, is the full title.]

Spencer begins by arguing that the constancy of human nature, so frequently alleged, is a fallacy.  For change is the law of all things, of every single object as well as of the universe.  “Nature in its infinite complexity is ever growing to a new development.”  It would be strange if, in this universal mutation, man alone were unchangeable, and it is not true.  “He also obeys the law of indefinite variation.”  Contrast the houseless savages with Newtons and Shakespeares; between these extremes there are countless degrees of difference.  If then humanity is indefinitely variable, perfectibility is possible.

In the second place, evil is not a permanent necessity.  For all evil results from the non-adaptation of the organism to its conditions; this is true of everything that lives.  And it is equally true that evil perpetually tends to disappear.  In virtue of an essential principle of life, this non-adaptation of organisms to their conditions is ever being rectified, and one or both continue to be modified until the adaptation is perfect.  And this applies to the mental as well as to the physical sphere.

In the present state of the world men suffer many evils, and this shows that their characters are not yet adjusted to the social state.  Now the qualification requisite for the social state is that each individual shall have such desires only as may fully be satisfied without trenching upon the ability of others to obtain similar satisfaction.  This qualification is not yet fulfilled, because civilised man retains some of the characteristics which were suitable for the conditions of his earlier predatory life.  He needed one moral constitution for his primitive state, he needs quite another for his present state.  The resultant is a process of adaptation which has been going on for a long time, and will go on for a long time to come.