I Think II


Contradictions on Natural Selection

Charles Darwin’s innumerably long “I Think” arguments to sell his natural selection theory eventually resulted in contradictions in The Origin of Species on 15 major aspects of evolution. Contradictory aspects include, power, perfection, chance, and advantages.  Other contradictions are presented in length in Darwin, Then and Now.




Darwin argued –

“It has been said that I speak of natural selection as an active power or Deity; but who objects to an author speaking of the attraction of gravity as ruling the movements of the planets?”


“What limit can be put to this [natural selection] power, acting during long ages and rigidly scrutinising the whole constitution, structure, and habits of each creature, favouring the good and rejecting the bad? I can see no limit to this power, in slowly and beautifully adapting each form to the most complex relations of life.”

Then, Darwin contradicted his own argument –

“Natural selection will be powerless in certain beneficial directions.”


Darwin argued –

“There is no logical impossibility in the acquirement of any conceivable degree of perfection through natural selection.”

Then, Darwin contradicted his own argument –

“Natural selection will not produce absolute perfection, nor do we always meet, as far as we can judge, with this high standard under nature.”


Darwin argued against the role of chance in natural selection –

“I was so convinced that not even a stripe of colour appears from what is commonly called chance.”

Then, Darwin contradicted his own argument  –

“As many more individuals of each species are born than can possibly survive; and as, consequently, there is a frequently recurring struggle for existence, it follows that any being, if it vary however slightly in any manner profitable to itself, under the complex and sometimes varying conditions of life, will have a better chance of surviving, and thus be naturally selected.”


Darwin argued –

“What natural selection cannot do, is to modify the structure of one species, without giving it any advantage, for the good of another species.”

Then contradicted his own argument –

“Natural selection can and does often produce structures for the direct injury of other animals.”



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Darwin, Then and Now is a journey through the most amazing story in the history of science - the history of evolution. The book encapsulates who Darwin was, what he said, and what scientists have discovered since the publication of The Origin of Species in 1859.

With over 1,000 references, Darwin Then and Now is a historical chronicle of the rise and fall of the once popular theory of biological evolution.