William Lawrence (1783-1867)
Nature has provided, by the insurmountable barriers of instinctive aversion, of sterility in the hybrid offspring, and in the allotment of species to different parts of the earth, against any corruption or change of species of wild animals. We must therefore admit, for all the species which we know at present, as sufficiently distinct and constant, a distinct origin and common date. ( Lectures on Physiology, Zoology, and the Natural History of Man, 1819).
Sometimes, being elevated to the status of an early evolutionist runs counter to the actual evidence. Such is the case of William Lawrence, whose views above, make amply clear that he was not an evolutionist. However, this did not prevent C.D. Darlington from referring to Lawrence as a “precursor to Darwin” whose “book made it clear that the theory of evolution was bound up with ideas that would destroy both the Church and the governing class.” That said, there is much that is radical in Lawrence’s 1819 Lectures on Physiology, Zoology, and the Natural History of Man: his starkly materialist view of the human mind, his position that humans should be studied like any other species of animal, his outright rejection of Lamarckian (and prevailing) views of the inheritance of acquired characteristics, and his unswerving insistence on scientific inquiry unfettered by academic or theological authority.
The overarching project of Lawrence’s book is to advance the idea that the different human races are members of a single species (monogenism) as opposed to separately created species. Lawrence located human beings within a natural, or zoological, classification. His radical materialist philosophy of mind claimed that cognition resulted entirely from an animal’s structural organization, and he viewed the difference between man and the smallest creatures on Earth as one only of degree:
“If the intellectual phenomena of man require an immaterial principle superadded to the brain, we must equally concede it to those more rational animals which exhibit manifestations differing from some of the human only in degree. If we grant it to these, we cannot refuse it to the next in order, and so on in succession to the whole series, – to the oyster, the sea-anemone, the polype, the microscopic animalcules.” (96)
The prevailing Lord Chancellor apparently took these kinds of views to be an implicit denial of Christian theological tenets. As a consequence of this radicalism, Lawrence’s 1819 Lectures on Physiology, Zoology, and the Natural History of Man was suppressed and its copyright revoked (though later editions were printed illegally and were widely available).
What makes Lawrence’s writings feel consistent with a modern understanding of evolutionary process are his considerations of inheritance and heredity, as well as his views on the formation of varieties and races in humans, other animals, and plants. Lawrence clearly recognized the possibility of heritable biological novelty arising in a population that could then be passed on and spread and categorically rejected the inheritance of acquired characteristics:
“It is obvious that the external influences just considered [i.e. the operation of climate] …would still be entirely inadequate to account for those signal diversities, which constitute differences of race in animals. These can be explained only by two principles already mentioned; namely, the occasional production of an offspring with different characters from those of the parents, as a native or congenital variety; and the propagation of such varieties by generation.” (469)
Moreover, Lawrence conceived of the additional power of geographic isolation of populations leading to the creation of distinct races:
“Let us suppose that the porcupine family [humans with a hereditary disease causing bristly protrusions from the skin] had been exiled from human society, and been obliged to take up their abode in some solitary spot or desert island. By matching with each other, a race would have been produced, more widely different from us [Caucasians] in external appearance than the Negro.” (pg. 390 in 1822 Natural History – also qtd in Wells)
Lawrence never used any of his evidence on individual and population-level variation giving rise to new races and varieties to articulate a theory of evolutionary change over longer periods of time. Nevertheless, in Descent of Man (1871), Darwin cited Lawrence’s observations on the outcomes of sexual selection in human populations as evidence of evolutionary change induced by selective breeding. Alfred Russel Wallace was also well versed and deeply impressed by Lawrence’s Lectures.
For additional treatment of Lawrence’s writings in an evolutionary context, please see Kentwood Wells’ “Sir William Lawrence (1783-1867) A Study of Pre-Darwinian Ideas on Heredity and Variation.”