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conditions,' and makes consequently some criticisms which are entirely wide of the mark and 
might have been couched in more courteous terms." The inference here is that I carelessly 
read the Report and assumed that its object was specially to investigate the existence or non- 
existence of selection. I did no such thing, for in my memoir the word written is not " specially " 
but " specifically " (p. 8), and the charge of careless reading must recoil on the reviewer. I never 
for one moment thought that the Report was specially concerned with that problem ; its chief 
object was the exceedingly important one of the determination of the distribution and causes of 
excessive infantile mortality. That one of the specific objects of the Report was to determine 
if selection existed cannot be denied. The first of the three objects stated on p. 1 of the Report 
reads " to determine, on the basis of our national statistics, whether reduction of infant mortality 
implies any untoward influence on the health of survivors to later years." Again, on p. 9, 
"attempts to reduce infant mortality are regarded by many as an interference with natural 
selection, which must be inimical to the average health of those surviving.... The statistics 
in the following pages do not support this view." In the memoir I have given reasons for the 
opinion that the statistics referred to do nothing of the kind, though here I am only concerned 
in showing that the author of the Report intended part of it to refer to the problem of selection. 
Other quotations to the same end could be given from the Report, though it is true that on p. 17 
there is another statement which contradicts them all. I need not quote from the many news- 
paper accounts of the Report in support of my contention that I did not carelessly assume it to 
deal with the problem of selection, but I will cull a statement from the review in our own Journal 
(Jan. 1911, p. 208), "Perhaps the most striking conclusion of the report — which is admittedly 
of a somewhat provisional character in the absence of an extended series of annual statistics of 
the kind given — is the proof that the alleged selective effect of infantile mortality is not supported 
by the data available : there may be a slight selective influence extending to the second or third 
year of life, but it is exceedingly slight at best." 
I regret that the charge of discourtesy should be made against me, as 1 attempted throughout 
to be studiously courteous, and the Journal critic is the first one who in speaking of my attitude 
to the Report has expressed the opinion that I have erred on the side of under-courtesy. On 
re-reading my words the only sentence I can find which, I think, remotely admits of the charge 
made is one in which reference is made to the fact that, in the Report, those who have spent 
months in the laborious collection of facts and figures relating to the problem, and have come 
to the conclusion that selection is operative, are pilloried with the offensive label a " school of 
thought." I shall be grateful if the reviewer will point out to me the passages to which he 
refers, for other critics have expressed the opinion that I was too favourable in my attitude 
to the Report. 
Finally I should like to summarise the evidence we have at present as to the existence of 
a selective death-rate in man. Full references to the originals are given both in the Current 
Note and in the memoir. Fuller details are given in the latter. 
(a) The work of Miss Beeton and Prof. Pearson. This was indirect, but its results have 
never, so far as I am aware, been called into doubt, and have long been accepted by the scientific 
world. The authors showed that at least from 50% to 70% of all deaths were due to selective 
action. 
(b) The investigation of Prof. Ploetz on German data. The result of this was to show that 
at least 60 % of the mortality at ages less than five was due to selective causes. 
(c) The recent report of the Medical Officer of the Local Government Board and Mr Yule's 
Appendix to it. This is the only work, whose existence I am aware of, which, since the publica- 
tion of (a), has appeared to call into doubt the operation of a selective death-rate. I have 
elsewhere given reasons against the validity of that work, and Mr Yule's statement as to the 
tentative nature of its results has often been quoted. 
