What is of interest to us, however, is Darwin’s attitude toward his more immediate predecessors, Buffon, Lamarck, Chambers, etc. This attitude has been a matter of much comment by Samuel Butler and others and it is not perfectly easy to understand. That Darwin in his earlier thinking as well as in his later was influenced by previous investigators is evident enough, for instance in touches like that in the ‘Voyage of the Beagle’: ‘Nature by making habit omnipotent, and its effects hereditary, has fitted the Fuegian to the climate and productions of his miserable country.’[391] Also, his frequent comments show that he knew what had been written before him and had profited by it, and in the later editions of the ‘Origin’ he took some pains to acknowledge the obligation. Yet his tone in his letters is by no means respectful and of Lamarck especially, who had done the most, it is difficult for him to speak without a sneer. Thus, in 1844 he writes: ‘Heaven forefend me from Lamarck nonsense of a “tendency to progression,” “adaptations from the slow willing of animals,” etc.! But the conclusions I am led to are not widely different from his; though the means of change are wholly so.’[392] Again, a little later: ‘With respect to books on this subject, I do not know any systematical ones, except Lamarck’s which is veritable rubbish.’[393] And later still, in 1859, he writes to Lyell: ‘You often allude to Lamarck’s work; I do not know what you think about it, but it appeared to me extremely poor; I got not a fact or idea from it.’[394]