PREFACE TO THE SECOND EDITION 
After some years had passed subsequent to the publication 
of this book in 1883, its publishers, Messrs. Macmillan, 
informed me that the demand for it just, but only just 
warranted a revised issue. I shrank from the great trouble 
of bringing it up to date because it, or rather many of my 
memoirs out of which it was built up, had become starting- 
points for elaborate investigations both in England and in 
America, to which it would be difficult and very laborious 
to do justice in a brief compass. So the question ofa Second 
Edition was then entirely dropped. Since that time the 
book has by no means ceased to live, for it continues to be 
quoted from and sought for, but is obtainable only with 
difficulty, and at much more than its original cost, at sales 
of second-hand books. Moreover, it became the starting- 
point of that recent movement in favour of National 
Eugenics (see note p. 24 in first edition) which is recognised 
by the University of London, and has its home in University 
College. 
Having received a proposal to republish the book in its 
present convenient and inexpensive form, I gladly accepted 
it, having first sought and received an obliging assurance 
from Messrs. Macmillan that they would waive all their claims 
to the contrary in my favour. 
The following small changes are made in this edition. 
The illustrations are for the most part reduced in size to 
suit the smaller form of the volume, the lettering of the 
composites is rearranged, and the coloured illustration is 
reproduced as closely as circumstances permit. Two 
chapters are omitted, on “ Theocratic Intervention ” and on 
the “Objective Efficacy of Prayer.” The earlier part of the 
latter was too much abbreviated from the original memoir 
in the Fortnightly Review, 1872, and gives, as I now perceive, 
a somewhat inexact impression of its object, which was to 
investigate certain views then thought orthodox, but which 
are growing obsolete. I could not reinsert these omissions 
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