Marx and Engels in their commentary on Darwin spoke of his materialism as ‘mechanical’, to be distinguished from their own dialectical and historical materialism. The supernatural, and hence religious belief, was simply redundant in biology’s account of human nature. Within the very different materialism of Marx, religion is theorised as ‘the sigh of the oppressed creature, the heart of a heartless world, just as it is the spirit of a spiritless situation. It is the opium of the people.’ It is difficult to think of two materialisms further apart. Writing to Engels some three years after the publication of The Origin, Marx, recognising Darwin’s dependence on Malthus, anticipates a central premise of science studies – the mutual shaping of science and society:
This is not how mainstream biologists read Darwin’s theory of evolution. Instead of problematising his reproduction of the Victorian social order within The Origin, they read out his embrace of capitalist political economy and the sexism and racism which for him were integral to nature’s laws. For mainstream biologists the true reading is neutral, having nothing to do with the social order. It is the meticulous study of the natural order and the illumination that evolutionary theory casts upon it. Since for biologists humans are part of this natural order, the theory that applies to non-humans applies to them as well? In the intervening century and a half, biologists have continued building on Darwin by insisting on a materialist account of nature in general and of human nature in particular, from our basic physiology to our powers of cognition, our emotions and beliefs. As we will discuss in later chapters, the current project of the neurosciences to explain not only the brain but the mind, and indeed consciousness itself, seeks to realise Darwin’s fundamental premise.
The book’s resonances were widely shared and despite religious objections evolutionary theory was becoming part of the wider culture. For Spencer, Darwinian natural selection provided the explanation for why laissez-faire liberalism required a brutal ‘struggle for existence’. Darwin, despite regarding Spencer’s work as speculative, later adopted the term – and even later regretted having done so. Had he instead adopted the Russian anarchist and biologist Prince Peter Kropotkin’s ‘struggle for life’ in which mutual aid, not mere existence, was a driving force in evolution, the naturalising gloom of Darwinism might have been averted. The proposition that it is not only competition but cooperation – both within and between species – which has been a major driving force in evolution, has run like a subterranean heresy through most of the evolutionary theorising of the last century. Only now – as we discuss later in this chapter – has it re-emerged into the daylight of mainstream thinking.