To Louis Agassiz 11 November 
Down Bromley Kent [Ilkley]
My dear Sir
I have ventured to send you, a copy of my Book (as yet only an abstract) on the origin of species.1 As the conclusions at which I have arrived on several points differ so widely from yours, I have thought (should you at any time read my volume) that you might think that I had sent it to you out of a spirit of defiance or bravado;2 but I assure you that I act under a wholly different frame of mind. I hope that you will at least give me credit, however erroneous you may think my conclusion, for having earnestly endeavoured to arrive at the truth.
With sincere respect, I beg leave to remain | Yours very faithfully | Charles Darwin
Sends copy of Origin.
Please cite as
Darwin Correspondence Project, “Letter no. 2519,” accessed on 28 October 2016, http://www.darwinproject.ac.uk/DCP-LETT-2519