According to Mr. Spencer, we are bound to accept Ethics as part of the process of cosmical equilibration for this is after all the main conception of Mr. Spencer's great work. The apparent and ostensible conception, and that with which he has most succeeded in impressing the public mind, is the principle of evolution or gradual development; but we must not lose sight of the fact that what he proposed to accomplish was an explanation of evolution, and not merely the establishment of its historical verity. This explanation is in terms of equilibration. That conception lies behind and above the celebrated "Formula of Evolution," and by means of it the fanciful law of the moving equilibrium is posited as the ruling principle of biological change and development, as well as of physical changes proper. The biological law, or law of the moving equilibrium, rules supreme over all actions and developments of organisms: and even if an additional factor of subjectivity is present as one of the forces which equilibrate in a moving equilibrium, it is, nevertheless, subject to the laws of equilibration. It is not yet made clear how the law of equilibration, which necessitates that all forces should come to a state of rest in as speedy a time as possible, can be changed into a biological law working in the antagonistic direction of the self-preservation of a set of motions, and their self-protection against a possible cessation or extinction, with the addition of means of reproduction in view of an eventual cessation or extinction. But it is these biological actions, some of them purposive, and some of them perhaps not consciously purposive, which have to be properly shown as part of the cosmical process of equilibration, before purposive actions, and therefore, before Ethics can be explained upon cosmical principles. ERRATA. Page xiii, lines 1 and 13, for "actors" read "factors." Page ii, line 18, for "he bridges over" read "he is supposed to bridge over." Page 38, line 27, at the end, delete "in the." Page 43, heading, for "The Philosophical View" read "The Biological View." Page 47, line 27, for "Ethics" read "of Ethics." Page 51, line 7, for "ætheticism" read "æstheticism." Page 74, line 14, for "eges" read "egos." Page 88, line 28, for "pervented" read "prevented." End of Project Gutenberg's On Mr. Spencer's Data of Ethics, by Malcolm Guthrie