“It were unwise to be sanguine and unphilosophical to despair” – John Playfair, 1814.

In an essay of 1888, with the novels on which his reputation rests both completed, Samuel Butler reflected on how he might describe himself. “Philosophical writer” was the best fit, he concluded, even if any close reader of Butler will agree it was a rather loose fit. His best known intellectual progeny are as various and contrasting as you might expect from a talent which itself eludes any simple definition.

Saul Bellow re-printed Butler’s ‘Ramblings in Cheapside’ in ‘The Noble Savage’, a little magazine he ran in the 1960s, hoping it would ‘get writers into the world again.’ As a translator of both the Iliad and the Odyssey Butler's theory that the latter must have been written by a woman in western Sicily was later dusted off and re-used by Robert Graves in his Greek Myths. Asked to write about “a book which has influenced me”, E.M.Forster chose Butler's satire Erewhon, liking it all the more for being “hard to classify”.

Butler was also involved in the Victorian debate on evolution. Fifty year later his ideas on the subject were taken up by George Bernard Shaw, incorporating them into his own critique of Darwinism, Back to Methuselah. It's from this less familiar, less literary end of his pre-occupations – namely his thinking on memory and evolution – that I want to begin. Butler wrote at a time when first-class writers were still, just, permitted to attempt some grand synthesis. His engagement with, and competence across, such a wide range of literary forms and subject matter seem rather forbidding a century after his death. But we can always take refuge in sneering at him as a dilettante or 'Victorian sage' if they make us too uncomfortable.

He read Darwin’s The Origin of Species the year it came out, in 1859. He was then a young man who had just declined to follow his father and grandfather into ordained ministry in the Church of England. The book caught his imagination and he was to meet Darwin himself in the 1860s. His enthusiasm was later tempered, however, by the feeling that the extreme material determinism of Darwin's version of natural selection was itself an over-reaction to the 'Bible fetishism' of the early 19th century. As for many of his intellectual contemporaries, elaborating a response to Darwin was a life-long under-taking. Butler was to write, most famously, that Darwin had “banished mind from the universe”. He came to reject a theory of human development in which “habit, effort and intelligence acquired during the experience of any one life goes for nothing […] such a nightmare of waste and death is as baseless as it is repulsive,” he wrote.

Butler was of course a man of his times but his criticisms were not those of the Biblical literalism which he had rejected in his twenties, even before reading Darwin. He fully accepted evolution as a fact. In the recent debate on sociobiology, in the 1980s and 1990s, the Victorian debate on evolution was often caricatured as one which pitted the Biblical die-hards against the unclouded vision of the secularising new wave. No prizes for guessing which side came off more glamorously in this re-imagined version of events. But Bishop Wilberforce was present in the much-mythologised 'confrontation' with T.H.Huxley as a scientist and as vice-president of the Royal Society, not as a bishop. The real debate was a much more nuanced issue and Butler is still one of the best ways into it.

He took his writings on the matter seriously and there is little in them of the oblique humour of his other work. He was of course, a man of his times. He believed things to be factually true which have been disproved since. He guessed things wrong. So did Darwin. Darwin had observed the differentiation of species and had posited natural selection as the explanation for it. But since neither Darwin nor anyone else knew how any given trait was transmitted from one generation to the next, he could not know how his 'natural selection' worked at the individual level. He posited 'gemmules' as the entities responsible, but could offer only the vaguest explanation of what these were or what they did.

Gregor Mendel, an Augustinian monk and school teacher, presented his 44-page monograph to Brno's Natural History Society in 1865. He would remain best known in his life-time as Brno's weather man – three times a day for twenty-seven years he collected meteorological data, sending them to the weather centre in Vienna. His monograph made little impression in Brno and none at all in the outside world until its 're-discovery' in 1900.

That leaves forty years between On the Origin of Species and the first awareness of Mendel's laws of inheritance, the very years in which Butler worked as a 'philosophical writer'. The significance of this is that, with no way of explaining the transmission of characteristics, or how 'accidental variations' could arise, the Lamarckian argument could still stand – and indeed, as we shall see, there are still traces of it even in Darwin's work. Butler was among those who could not accept that any theory of evolution 'undirected by will, effort and intelligence' would ever stand the test of time. He himself placed that intelligence firmly inside the species not outside it, allowing chance a secondary role in his system.

The discovery of Mendel's Laws, and then DNA, finally put paid to the Lamarckian theory of evolution. It seemed the idea of a creature that could 'will' its own evolutionary direction was quite untenable. The genetic blue-print we pass on is the one we are born with and it operates quite independently of any use we make of it or any plans we may have for it.

But let us remind ourselves again of the nub of the recent debate about socio-biology: How much of our behaviour is inherited and determined genetically? The Edward O. Wilsons and the Richard Dawkins' answer: all of it. Their opponents: some of it. The factual landscape has altered out of all recognition but the underlying disagreement shows striking affinity with, let us say, a famous ancestor. Summarise the socio-biology debate a slightly different way: does our behaviour operate by the laws, albeit rich and complex, of material determinism? Is there any sense in which we can operate independently of those laws?

Put it like that and suddenly it's a debate Butler would have recognised at once. For him 'will, effort and intelligence' had been allotted no role in Darwinian theory, which meant the theory must eventually be proved wrong. Compare that with some words from Mary Midgley, referring in 1985 to Dawkins' theory about the 'selfishness' of our genes: “What is supposed to follow from this for our understanding of life is an arbitrary, selective debunking of all non-egoistic motivation”.

What our genes do or do not determine ought perhaps to be a 'purely scientific' debate, but of course eminent (and not so eminent) scientists are no more able than anyone else to resist arrogating to themselves the role of prophet. As Midgley wryly observes, with a sidelong glance at the zealots of socio-biology: “Extravagance is not eliminated merely by becoming anti-religious”.

For Steve Jones or the late Stephen Jay Gould, by contrast, the jury on such questions is very much still out. The MIT geneticist Evelyn Fox Keller has recently argued that in our fascination with variability, as one of natural selection's 'motors', we have missed the no less remarkable 'robustness' or 'reliability' which can sustain a species over millions of years. She wonders how “structures whose function is to provide pockets of resistance to the disordering forces of chance” ever arose? Or as the geneticist Theodosius Dobzansky put it: “This dichotomy [between pure chance and pure necessity] is spurious. Evolution […] is governed by natural selection, in which ingredients of chance and anti-chance are blended”.

Again Butler would have been fascinated by the new science but the arguments over it would have had a familiar ring. Just as he placed a creature's vital intelligence inside the creature and scorned a version of evolution that was driven by nothing but chance, so now geneticists come to marvel at creatures as, in part, mysteriously capable of just such 'pockets of resistance' to chance.

It's precisely because of the resonance between these two debates that the 19th century one is so often invoked, and so often inaccurately, by participants in the current one. Coming to terms with a more grown-up version of events still matters, then. Butler was not treated as a major player at the time but his arguments offer valuable insights into the real debate, as it was going on then and still is going on – the one which the popularisers wisely steer clear of. Chiaroscuro always sold better.

In Butler's personality, as he broke with orthodox religious belief, of course the new and bracing currents of thought washed in among the old. But he was not so craven as to pretend that they had simply washed away all trace of or influence from the older civilisation which had formed him. “The Christianity that can be taken up and laid down as if it were a watch or a book is Christianity in name only” he wrote. And what was the essence of a still-believable Christianity? “Unflinching opposition to the charlatinisms and Pharisaisms of a man's own times […] Faith does not consist, as the Sunday School pupil said, 'in the power of believing that which we know to be untrue' “.

By his deeply thought-through, unhysterical rejection of the Church, he avoided much of the worst of Victorian secularist hysteria likewise. And might perhaps have something sensible to offer us, caught as we all are in the religious / secular schism of our own day.

Evolution, as we've seen, as the explanation of our biological origins, never troubled him, though he contested Darwin's claim to have been the first to understand it. He preferred to trace the idea's gradual formation since Buffon in the 18th century. Indeed, as he pointed out, Darwin is at times less of a Darwinist himself than many of his followers. “To suppose that the eye, with all its inimitable contrivances […] could have formed by natural selection, seems, I freely confess, absurd in the highest possible degree”. Or again, “disuse, aided sometimes by natural selection, will often tend to reduce an organ, when it had become useless by changed habits or under changed conditions of life; and we can clearly see on this view the meaning of rudimentary organs”. This latter is, of course, pure Lamarck. Both quotations are from On the Origin of Species. Butler delighted to 'expose' such inconsistencies in the great work.

And in doing so was more spiteful than was justified. Darwin read and re-read Paradise Lost during the Beagle Voyage and was to express regret in later life at no longer being able to read poetry with pleasure. He was indeed less of a 'Darwinist' than many who lay claim to his mantle even today. Of his wide reading as a young man Midgley writes: “The result of this long preliminary pilgrimage was to make his own picture unusually balanced and inclusive […] The vastness of truth and the one-sidedness of formulae always haunted him”.

Butler's own apprenticeship to the 'examined life' was also a long if very different one, to which the excellence and variety of his output attest. And he was not only critical of Darwin – he constructed a theory of natural selection of his own. Adapting the theory of an Austrian scientist, he proposed to consider heredity as a form of memory, “an extension of memory from one generation to another”. He believed that the habits successively acquired by our ancestors are downloaded into the embryo during gestation, and asserted that if we are inheriting, developing and passing on such habits then we are in one sense identical with all our ancestors, and all our descendants. The development of an embryo, then, is “repetition of a lesson learned by rote”.

He was more than ready for the response to this: “From the point of view of the law courts and everyday life it is, of course, nonsense. The common sense view of the matter to people who are not over-curious and to whom time is money, will be that a baby is not a baby until it is born and that when born it should be born in wedlock […] But in the kingdom of thought, as in that of heaven, there are many mansions, and what would be extravagance in the cottage or the farmhouse, as it were, of daily practise, is but common decency in the palace of high philosophy, wherein dwells evolution”.