Herbert Spencer an Ernst Haeckel, Brighton, 26. Oktober 1901
5 Percival Terrace,
Brighton
Oct. 26, 1901
My dear Sir,
I received recently the copy of your work The Riddle of the universe etc. translated by Mr Joseph McCabe. From the words of the memorandum accompanying it I infer that I have to thank you for this gift.
From the closing pages of chapter 6 I infer that you have not seen the Principles of Psychology, and this is the more remarkable since in The Origin of Species (in all || 2 editions save the first) Darwin refers to it as having in 1855 laid the foundation of the evolutionary view of mind. That the contents of the work should have been overlooked or forgotten seems to me the more strange because, unless I was misinformed, it was at your instigation the late Dr Vetter undertook the translation of my works.
I am,
faithfully yours
Herbert Spencer
Prof. Dr Ernst Haeckel.