Marx-Engels Correspondence 1866

Engels To Marx
In London

Source: MECW Volume 42, p. 322;
First published: in Der Briefwechsel zwischen F. Engels und K. Marx, Stuttgart, 1913.

Manchester, 5 October 1866

Dear Moor,

I am tickled by your naivety in having bills outstanding against you without knowing the amount; however, it’s lucky the difference was no bigger and the good baker was at hand. So that you can repay the sum in question to that excellent man at once and thus preserve your credit, I am enclosing £5 I/F 59667, Manchester, 30 January 1865, for you, and am also returning the bill now settled.

Ad vocem Trémaux. When I wrote to you, I had admittedly only read a third of the book, and that was certainly the worst part (at the beginning). The second third, the critique of the schools, is far better; the third, the conclusions, very bad again. The man deserves credit for having emphasised the effect of the ‘soil’ on the evolution of races and logically of species as well more than had previously been done, and secondly for having worked out more accurate (though, in my view, still very one-sided) views on the effects of crossing than his predecessors. In one respect, Darwin is also right in his views on the effect crossing has in producing change, as Trémaux incidentally tacitly acknowledges, in that, when it suits him to do so, he also treats crossing as a means of change, even if ultimately as one that cancels itself out. Similarly, Darwin and others have never failed to appreciate the effect of the soil, and if they did not especially emphasise it, this was because they had no notion of how the soil exerts an influence — other than that fertility has a favourable and infertility an unfavourable effect. And Trémaux is little the wiser about that either. The hypothesis that, as a general rule, the soil favours the development of higher species to the extent that it belongs to more recent formations, sounds exceedingly plausible and may or may not be correct; however, when I see the ridiculous evidence with which Trémaux seeks to substantiate it, of which 9/10 is based on erroneous or distorted facts and the remaining 1/10 proves nothing, I cannot but extend the profound suspicions I have of the author of the hypothesis to the hypothesis itself. But when he then goes on to declare that the effect of the soil’s greater or lesser age, modified by crossing, is the sole cause of change in organic species or races, I see absolutely no reason to go along with the man thus far, on the contrary, I see numerous objections to so doing.

You say that Cuvier also criticised the German natural philosophers for their ignorance of geology when they proclaimed the mutability of species, and yet they were proved right. At that time, however, the question had nothing to do with geology; but if someone puts forward a theory of the mutability of species based on geology alone and makes such geological howlers in it, falsifies the geology of whole countries (e.g., Italy and even France) and takes the rest of his examples from countries of whose geology we are as good as totally ignorant (Africa, Central Asia, etc.), then that is altogether a different matter. With regard to the ethnological examples in particular, the ones that concern countries and peoples which are generally known are almost without exception erroneous, either in their geological premisses or in the conclusions drawn from them — and he completely ignores the many contrary examples, e.g., the alluvial plains in Central Siberia, the enormous alluvial basin of the River Amazon, all the alluvial land southward from La Plata almost to the southern tip of America (east of the Cordilleras).

That the geological structure of the soil is closely related to the ‘soil’ in which everything grows is an old idea, likewise that this soil which is able to support vegetation influences the flora and fauna that subsist on it. It is also true that this influence has as yet been scarcely examined at all. But it is a colossal leap from there to Trémaux’s theory. At all events, he deserves credit for having emphasised this previously neglected aspect, and, as I said, the hypothesis that the soil encourages evolution in proportion to its greater or lesser geological age, may be correct within certain limits (or again it may not), but all the further conclusions he draws I consider to be either totally mistaken or incredibly one-sided and exaggerated.

I was very interested by Moilin’s book, particularly for the results the French have obtained by vivisection; it is the only way to ascertain the functions of certain nerves and the effects of interfering with them; these fellows appear to have taken the art of animal-torture to a very high level of perfection; and I can very well understand the hypocritical fury of the English against vivisection; these experiments no doubt came as a most unpleasant surprise to many of the comatose gentlemen here and overturned many of their speculations. Whether there is anything new in the theory of inflammations, I am in no position to judge (I intend giving the book to Gumpert); this whole new French school does, however, appear to have a certain free-and-easy character, making big claims and being rather less scrupulous with evidence. As regards medicines, it contains nothing that any competent German doctor does not also know and accept; Moilin just forgets that 1. one is often obliged to choose the lesser evil, medicine, in order to get rid of the greater, namely, a symptom which in itself represents a direct danger, in exactly the same way that by surgery one destroys tissues where there is no alternative, and 2. that one does have to stick to the medicines for as long as one has nothing better. As soon as Moilin can cure syphilis with his electricity, mercury will soon vanish, but scarcely until then. Incidentally, no one can go on telling me that only the Germans can ‘construct’ systems, the French beat them hollow at that.

Kindest regards.

F. E.