The more routes for knowledge contamination, reason has it, the greater the probability that one was taken.
Can we rationally ruminate on the likelihood of Darwin's guilt as a plagiarist from what remains of the lost, stolen or deliberately destroyed by Darwin, correspondence we have from him and his friends and associates? Well, we certainly can in light of the proven lies Darwin wrote in his letters and his book "The Origin of Species", including his confession to Joseph Hooker that he lied by claiming Patrick Matthew's theory was buried in only the Appendix of his book. Other than that, no one has any real idea what scandal or gossip Victorian men of science involved themselves in outside the world of their formal letters. Looking at the worst side of Victorian life and values, how many - for example - might have availed themselves of the plight of child prostitutes during their trips to London? We have zero idea on that one. Maybe some did. Maybe none did.
One thing is for sure however, and that is that Darwin and his associates and his influencers and his influencer's influencers were not exactly what they pretend to be in their correspondence. Who is? Writing that is no more speculative - in my mere opinion - than the reasoned opinion of anyone else that it is unlikely any of those who cited Matthew's 1831 book shared the ideas they read in it with Darwin or one of Darwin's friends or contemporaries, who could then have passed Matthew's ideas, or the title of the book containing them, on to Darwin. Why is it unlikely such a thing would happen? Unlikely based on what knowledge, as opposed to mere wishful thinking, is it unlikely?
Speculating, for example as some have, that the Vestiges would have been better had Chambers read Matthew is based on no more than a mere presumption that Chambers was a plagiarist - or else a presumption that he did not despise the Chartist Matthew (Chambers was famously very much against the vote for the working classes) - or that Chambers agreed fully with Matthew's theory. But the fact Chambers cited both of Matthew's books and famously loved reading and was supposed to have had a photographic memory is evidence his brain may well have been influenced by Matthew. We know, from admissions of it in their own correspondence and publications, that Chambers influenced both Darwin and Wallace. So Chambers is just one more newly unearthed route for knowledge contamination - via Chambers's The Vestiges of Creation book.
One major point here is the fact we know humans are very bad at keeping secrets. That acknowledgement of human behaviour is the exact same reasoning against conspiracy theories such as the daft idea of NASA's faked moon landing. Namely, too many people at NASA would have had to be in on it to keep it a secret. Correspondingly, the more people who knew about Matthew's ideas the more likely they shared them - or the title of the book containing them - directly with Darwin and/or via his other friends, associates and correspondents (so many of Darwin's letter are lost or else he destroyed them). Moreover, the list of those we newly know did read Matthew's ideas is growing.
Also, we know Matthew (at least if we believe him - and unlike Darwin he has never shown himself to be a liar) did discuss his ideas with that professor of a renowned Scottish University who feared to teach or write about them; as Matthew told us all in the Gardeners' Chronicle in 1860. And we know that in 1831 the United Services Journal told its readers - in writing - not to even contemplate Matthew's ideas on the laws of nature. So those then heretical ideas surely were spoken and written about pre 1858.
Then add to all of the above reasoning and evidence the proven fact that Darwin did not discover the theory of evolution by natural selection while on the voyages of the Beagle observing finch beaks in the Galapagos islands (see Sulloway 1983) but, by his own admission, got it from reading books, originally four-word-shuffled Matthew's earlier original "natural process of selection" name for his theory to its only grammatically possible equivalent "process of natural selection" (see Sutton 2017). Then, add to that fact the fact that earlier in his 1844 private essay (as Eiseley (1981) so importantly discovered) replicated Matthew's (1831) highly idiosyncratic foresters trees selected by mankind to be raised in nurseries versus those selected in the wild by nature - surely establishes on a balance of reasonable probabilities that the proven serial liar Darwin was at least influenced by Matthew pre-1858 and more likely than not read and deliberately plagiarized his book. Don't you think dear reader? And if that is not enough to convince you then consider that fact that as opposed to Darwin's proven lie (see Sutton 2014) that no naturalist read Matthew's (1831) bombshell breakthrough pre-1858 that several known to have influenced Darwin and Wallace and their influencers did so (see Sutton 2015). And to cap it all, add to that other lies Darwin told about his influencers not influencing him (see Dower 2009). Then, as if that is not enough to convince the most obstinate Darwin worshipper to rethink, on top of that cap we must consider the great weight of circumstantial evidence that the Big Data IDD method (Sutton and Griffiths 2018) unearthed on who was apparently first to be second in print with what the IDD method revealed are apparently original terms and phrases ('Matthewisms') coined by Matthew in his 1831 book. At which, point I must direct you to the current nonsense that the obscene and obsessed malicious cyber-stalker and Darwin fanatic Derry has added to the Patrick Matthew page on Wikipedia from the idiotic blog site of Dishonest Dagg The Plagiarist that I have mistaken books containing these Matthewisms for something other than what they so obviously are. The point is not what the publications that were apparently first to be second are about, but the possibility that those who wrote them might have been knowledge contaminated from reading directly or from someone else who read Matthew's book. Clearly, some of those who were first to be second with 'Matthewisms' were closely associated with Darwin (evidence here). A further discussion on the first to be second (F2B2) hypothesis can be found in this article, that is a response to a desperately disingenuous and essentially dishonest review of this area of my research.
Who edited the journal that published Blyths' influential articles on species and varities, articles that Darwin scholars know influenced Darwin, and some of Blyth's articles Darwin admitted influenced him? It was Loudon. What did Loudon read and review in 1832? It was Matthew's (1831) book. What did Loudon say it contained? Something seemingly original on the question of "origin of species", no less! That is evidence for a route of knowledge contamination from Matthew to Loudon to Blyth. But when it comes to the F2B2 question, my research (Sutton 2014) further uniquely unearthed the fact that Blyth's friend and twice co-author Rober Mudie (Mudie was born in Forfarshire - same Scottish county as Matthew) was apparently first to be second with Matthew's apparently unique term "rectangular branching".
So the routes for Matthewian knowledge contamination of Blyth are proven and should not be ignored. Blyth did not get the theory of evolution by natural selection into any of his papers - he thought species were immutable, but his very likely influencer Matthew (1831) did originate the theory. Not mentioning these facts - or seeking to bury them under lies - as Wikipedia does - would be cherry picking the data to suit the conclusion you wish to reach. Would it not?
Now we know the above facts do we not have a scientific duty to consider and weigh them?
And there is so much more evidence than this in my books (Sutton 2014 and 2017).
Just how many otherwise stunningly miraculous multiple "coincidences" are needed to sum the the probability they are not all a coincidence?
Darwin, by his own proven lying behaviour, has lost the right to be accorded the benefit of the doubt when it comes to any question of his honesty about his influencers.
I do think it is 100% proven on a balance of reasonable probabilities (the civil law) test of guilt - as opposed to 100% proven beyond reasonable doubt (the criminal test of guilt) that Patrick Matthew's (1831) theory influenced both Darwin and Wallace to plagiarise his theory in their paper of 1858 and in Darwin's (1859) Origin of Species.
A conversation via email with another Darwin, Wallace and Matthew scholar influenced me to write this section to this blog post Patrick Matthew. But who would know he influenced me to write this unless I wrote here that he did so and named him accordingly? For that reason, I have not attributed him as my influencer. That failure is not done out of meanness, but to prove my point that absence of evidence is not evidence of absence in a case such as this.
A smoking gun confession from Darwin or one of his cronies may well exist for those who insist upon it. And I know several places to go digging for it. But I'd need a large grant to fund that particular excavation project.
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