The Bloodless Revolution: Radical Vegetarians and the Discovery of India

In 1699 the anatomy lecturer at Surgeon’s Hall in London, Edward Tyson, made a breakthrough in the understanding of humanity’s relationship to beasts. For the first time in Western science, Tyson dissected the body of an ape, and to the fascination of all found that in nearly every way it resembled a human. He called it the ‘Orang-Outang’ – Malayan for ‘Man of the Woods’ – or in Latin, Homo sylvestris, and his specimen still stands in the upright posture of a human in the British Museum. The ‘Orang-Outang’ was in fact a young chimpanzee, but Tyson’s observations were nevertheless sensational and were still being consulted 150 years later when Charles Darwin (1809–82) devised his theory on the ‘missing link’.

Tyson’s chimp shed new light on the perennial question about the distinction between humans and animals: this ‘pygmie’, said Tyson, was ‘no man, nor yet a common ape but a sort of animal between both’. As far as he could see there was no difference between the two, even ‘the Brain in all Respects, exactly resembling a Man’s’. Contrary to expectations, Tyson believed this disproved the ancient atheist idea that man was just a sophisticated ape. In accordance with Descartes’ philosophy, Tyson argued that if there was no physical difference and yet animals still couldn’t speak or reason, man’s pre-eminence must reside in the ‘Higher principle’ of a rational soul. However, in the longer term, Tyson’s observations did lend force to the argument that humans were not essentially different from animals.

Tyson’s dissection has gone down as a landmark in the history of human self-knowledge, but its immediate impact is less well known. If the ape was corporally identical to humans, Tyson’s contemporaries began to wonder, mightn’t its habits tell us something about human nature? As one anxious reader (perhaps John Evelyn) scribbled in the margin of Tyson’s book Orang-Outang, King Charles I had to put down his court ape for being disturbingly lecherous.

Edward Tyson’s chimpanzee, before and after dissection (1699)

What about other natural appetites? Before he cut the poor chimp open, Tyson had been charmed by its virtuous temperance: it had got extremely drunk the first time someone gave it a jug of wine, but subsequently it restricted itself to just one glass with every meal, which proved, said Tyson, that the ‘Instinct of Nature teaches Brutes Temperance; and Intemperance is a Crime not only against the Laws of Morality, but of Nature too.’ The chimp also seemed to show that St Paul’s commandment against food taboos was a natural law, for it ate anything that was set before it, which – in the absence of any information on its natural feeding habits – led Tyson to suggest tentatively that ‘I can’t but think, (like a Man) that they are omnivorous.’

It is true that chimps do occasionally prey on monkeys but the ape we now call the orang-utan is exclusively herbivorous. Tyson and his contemporaries were confused about the difference between the great apes which made it difficult to collate behavioural observations with anatomical studies made back home. Travel books that Tyson quoted described other apes which ‘feed upon Fruits that they find in the Woods, and upon Nuts; for they eat no kind of Flesh’. If it was true that the apes were herbivorous and if their bodies were identical to man’s, wouldn’t that imply that humans were naturally designed to be herbivorous too? This set the stage for one of the most enduring and heated debates of the century: if man was an animal, what sort of an animal was he: carnivore or herbivore? What implications did this have for human nature: vicious or benign?1

Immediately after dissecting the ape, Tyson released a series of articles ‘On Man’s feeding on Flesh’ in the Philosophical Transactions of the Royal Society. These were written in response to the enquiries of the ex-medical student, now Oxford Professor of Geometry and founder member of the Royal Society, John Wallis (1616–1703). As if the turn of the century demanded a new direction in thinking, Wallis and Tyson formally set out the new agenda: that man’s eating of meat was to be scrutinised on an empirical, rather than scriptural, basis. ‘Without disputing it as a Point of Divinity,’ declared Wallis, ‘I shall consider it (with Gassendus) as a Question in Natural Philosophy, whether it be proper Food for Man.’2

As Wallis noted, the empirical vegetarian tradition had in fact been inaugurated seventy years earlier by the philosopher ‘Gassendus’, or as he is known today, Pierre Gassendi. Gassendi shared Descartes’ detestation of the fusty old Aristotelian scholasticism, but rejected Descartes’ excessively speculative rationalism, and emphasised instead that human knowledge is based on empirical sensory experience. Though less well known than his adversary today, Gassendi’s resuscitation of Epicurean atomism spawned one of the most important philosophical movements in Europe. He taught such writers as Cyrano de Bergerac (1619–55), the big-nosed libertin érudit, and influenced a whole school of eighteenth-century materialists, ultimately paving the way for modern atomic theories.3

Given Epicurus’ reputation as an arch-atheist and hedonist, Gassendi was sailing close to the wind by espousing his materialist philosophy and he was constantly fending off accusations of being an atheist and drunken libertine himself.4 But Gassendi insisted that Epicurus was misunderstood: his ethic of attaining pleasure meant avoiding pain by detaching oneself from fleshly appetites, and Epicurus proved this by living a heroically sober and temperate life. The Epicurean diet, said Gassendi, far from being a gluttonous feast, was more like that of peasants and Pythagoreans ‘who live on nothing but bread, fruit and water, and who maintain themselves to a marvel, without hardly ever having need of doctors’.5 Epicurus took his temperance so far that he allegedly maintained ‘a total abstinence from Flesh’.6

With regard to the allegations of atheism, Gassendi was a Catholic abbot and professed an implicit faith in man’s immortal soul; but in opposition to Descartes’ impassable line between spirit and matter, Gassendi thought of the soul as a rarefied substance like a flame which pervaded and animated the body. Descartes’ definition of animals as soulless, mindless and thoughtless machines was consequently fallacious, since they too had an animating soul even if it was not immortal.

Developing his objections to Descartes in unison with Hobbes, Gassendi suggested that as everything in the human mind came there only by the senses, and as animals had the same organs of sense as humans, it seemed clear that animals would think just like humans. Gassendi claimed that animal thoughts were not essentially different from ‘reason’ and differed only in the degree of their perfection: ‘though animals do not reason so perfectly and about so many things as man, they still do reason,’ Gassendi wrote to Descartes in 1641, ‘though they do not utter human expressions (as is natural seeing they are not man) yet they emit their own peculiar cries, and employ them just as we do our vocal sounds.’7

By this time Gassendi’s dispute with Descartes on behalf of the animals was more than a decade old. In 1629, soon after leaving the company of Descartes’ friends in Paris, Gassendi travelled to northern Europe where he met another of the greatest intellectuals of the period, the chemist Jan Baptista van Helmont (1579–1644), father of Franciscus Mercurius the kabbalist. Of all subjects they could have chosen, Helmont and Gassendi engaged in a debate about vegetarianism which they later pursued in letters to each other, and which Gassendi finally built into one of the most influential philosophical works of the seventeenth century, the Syntagma Philosophicum (posthumously published in 1658).

Like Tyson and Wallis decades later, Gassendi’s principal argument was based on comparative anatomy, a discipline as old as Aristotle. Gassendi adapted this part of his argument from Plutarch’s essay ‘On the Eating of Flesh’ (1st century AD). Man, Plutarch had argued, ‘has no hooked beak or sharp nails or jagged teeth, no strong stomach or warmth of vital fluids able to digest and assimilate a heavy diet of flesh.’8 For Plutarch, the corporal design of the human body indicated that nature intended humans to be herbivorous.

A millennium and a half later, Gassendi produced the mandate for philosophical vegetarianism, by proclaiming that ‘The entire purpose of philosophy ought to consist in leading men back to the paths of nature.’ He gave new precision to Plutarch’s anatomical argument by pointing out that carnivores had sharp, pointed, unevenly spaced teeth, whereas the teeth of herbivores were short, broad, blunt, and closely packed in jaws that joined perfectly for effective grinding. Human teeth, with their prominent molars and incisors, he said, were most like the herbivores. Gassendi concluded that ‘Nature intended [men] to follow, in the selection of their food, not the first, namely the carnivorous, but the latter, which graze on the simple gifts of the Earth.’ This observation, he said, was corroborated by the herbivorous diet instituted by God in Eden and by the myths of the classical Golden Age: ‘in this time of innocence,’ Gassendi speculated, ‘man did not want to drench his hands in the blood of animals.’ Because our teeth weren’t properly designed for chewing flesh, he said, they couldn’t cope with all the membranes, tendons and sticky fibres, leaving too much work for our stomachs, overcharging the system with succulent juices and clouding the spirits. Fruit and vegetables, on the other hand were easy to break down into pulp.

Helmont’s interpretation of the facts was totally different. He insisted that man was a microcosmic combination of all the animals: he had the canine teeth of carnivores and the molar teeth of herbivores, and could be nourished by the flesh of them all. That flesh also tasted delicious and nourished the human body was clear proof that ‘it was permitted to man by his nature, to eat the flesh of animals’.9

Gassendi retorted that the similarities between ourselves and animals – rather than being a mandate for eating them – should teach us to recognise our consanguinity. Taking a sideswipe at ‘a celebrated man’ (presumably Descartes), Gassendi argued that in terms of anatomy ‘monkeys can pride themselves on having the same as us’; ‘notwithstanding they are earthly, they are coeval with us, however much we are used to despising them.’

‘So how come you do not abstain from eating meat?’ Gassendi imagined his opponent asking, to which he replied that his nature had been depraved by being brought up a carnivore, and that it would be dangerous to change his diet all of a sudden (a pervasive assumption rooted in ancient medicine10). But nevertheless, he conceded, ‘I admit that if I were wise, I would abandon this food bit by bit, and nourish myself solely on the gifts of the earth: I do not doubt that I would be happier for longer and more constantly in better health.’11

It was ironic that Gassendi framed some of his arguments in opposition to Descartes, for this was just the sort of conclusion that Descartes appears to have come to. Perhaps when Descartes and Gassendi had their famous reconciliatory meeting in 1647, this was one of the topics they agreed upon. If the opinion of Descartes’ disciple, Antoine le Grand, is anything to go by, the Gassendists and Cartesians both agreed that humans were naturally herbivorous. In the Entire Body of Philosophy, According to the Principles of the Famous Renate des Cartes (1672), le Grand endorsed every point of Gassendi’s vegetarian argument. The fact that eating raw meat was instinctively repellent, he insisted, shows ‘that Flesh is not our Natural food, being only introduc’d by Lust, which hath quite changed our Nature from its Primigenial Inclination and Temper’. If a boy were raised on a natural fruitarian diet, le Grand speculated, he might ‘not be inferiour to Stags in running, nor to Apes in climbing of Trees’.12

Gassendi’s medical arguments developed into a long-lasting scientific tradition. This received a massive boost in 1678 when his major works were abridged and translated from Latin into French by an ex-pupil who had just returned from travelling in India and was now at the medical faculty of Montpellier.13 This vital redactor of Gassendi’s theories was no other than François Bernier, the most influential interpreter of Indian vegetarianism in seventeenth-century Europe – who suggested that abstaining from meat had originally been a rational practice based on the preservation of health and the inculcation of good morals. Although Bernier never said so in his travel writing, he had probably been predisposed to the medical arguments for vegetarianism by Gassendi, his friend and mentor.

In Bernier’s hands, Gassendi’s vegetarian arguments underwent a fascinating transformation. Gassendi had little empirical evidence that the vegetable diet really was as healthy as he hypothesised, but Bernier used his experience in India to show that vegetarians really were at least as healthy as meat-eaters. So, in Bernier’s Abrégé de la Philosophie de Gassendi, where Gassendi noted that ancient pagan philosophers and Christian ascetics lived on the vegetable diet, Bernier updated this information with the crucial contemporary fact that ‘even now many people of the East Indies still do’. Where Gassendi argued that the fortitude of herbivorous animals suggested that plants were very nourishing, Bernier inserted the comment that ‘the Indians who live on nothing else are just as strong, and at least as healthy as us’.14 And when Gassendi wrote that Diogenes, Seneca and Lucretius were exemplars of Epicurean frugality, Bernier appended an entire essay on the living ‘Indian Diogenes’, in order, he explained, ‘to shew that all these fine things we have spoken of, are not only bare Philosophical Speculations, but that there are whole Nations, who lead as sparing a Life’. The Brahmins, Banians and naked Indian fakirs eat hardly anything but lentils and rice, never eat flesh, and yet, said Bernier, ‘they live as contented, as quiet, and pleasant as we do, and far more Healthy, at least full as strong and lusty as we are.’15

Most intriguing of all – given his professional status as an academic physician – is Bernier’s attention to Indian medicine. Although he did not think much of their anatomical knowledge – and ridiculed them for fleeing every time he cut open an animal alive to demonstrate the circulation of the blood – he did think their medical practice could teach Europeans something, even though it ‘differs essentially from ours’. In his travelogue, Bernier noted that for Indians ‘the sovereign remedy for sickness is abstinence; nothing is worse for a sick body than meat broth.’ This went against the prevailing practice in France where feeble patients were considered in need of ‘strengthening’ with rich meat broths. And yet, Bernier noted that the Indian practice of abstinence from flesh seemed like an effective remedy, used by both Hindus and Muslims alike.16 In the Abrégé Bernier converted this into a full-blown defence of vegetarianism, arguing that meat broths did more harm than good and that ‘a great part of Asia believe them to be mortal to fever patients, and that this was, apparently, Hippocrates’ opinion, since he usually prescribes them nothing but oat broth’.17

Bernier adopted the Indian method of treatment by abstinence from flesh in his own medical practice: ‘I might mention also a Person of great Eminency, who was severely tormented with the Gout, but by my Advice, yielding to live one Year very abstemiously, and scarce to Eat any Flesh (according to the Custom of the Indians, who nevertheless are very healthy and strong, and are rarely troubled with such Distempers) was perfectly cured.’18 Indeed, Bernier had cured himself of such ailments as soon as he arrived in India. This, he extrapolated, was proof that vegetarianism was a healthy diet for anyone.

Not only did Bernier’s experience in India turn him away from the use of meat broths in medicine, it even seems to have convinced him that flesh-eating itself was bad for the health. Bernier, who despised Hinduism as a whole, ended up converting – at least on an intellectual plane – to what he saw as one of its principal doctrines.

Bernier forcefully injected the teaching of Indian medicine into the European tradition at exactly the time that other doctors were starting to revive the ancient Hippocratic use of therapeutic dieting. This was a medical reform that profoundly affected the understanding of lifestyle and which can be seen as the beginning of modern notions about balanced diets, the requirement of fresh vegetables and the nutritional viability of vegetarianism. Bernier thought the Indian doctors were leading the way.

In the 1670s the English philosopher John Locke (1632–1704), a doctor himself, spent fifteen months curing his own ailments among medical colleagues in Montpellier. He befriended Bernier, frequently quizzed him about India, avidly making notes in his diary on Indian physiology and metempsychosis; he read his travel narratives, which inspired him to study the other major works on Hinduism by della Valle, Lord, Roe, Ovington and Rogerius, and these provided the variety of cultural perspectives Locke employed in his Essay Concerning Human Understanding (1690).19 Locke agreed with Gassendi that animals could think, and he even seems to have been influenced by the ‘Hindu’ doctrine (reported by Rogerius) that humans were only more intelligent than animals because their brains (not their souls) were better constructed.20

It may also have been thanks to Bernier that, in his widely used educational guidebook Thoughts Concerning Education (1692), Locke joined Gassendi in criticising the custom of weaning children onto meat, suggesting that they would be much healthier if they ‘were kept wholly from flesh the first three or four years of their lives’ – a practice he recognised was hardly likely to catch on among parents who were ‘misled by the custom of eating too much flesh themselves’. Like Bernier, Locke also recommended that most children’s ailments should be cured by ‘abstinence from flesh’, and in a conclusion that foreshadowed the social critiques of later vegetarian doctors, Locke attributed ‘a great part of our diseases in England, to our eating too much flesh, and too little bread’.21 The anatomical vegetarianism of Gassendi merged with the Indian example observed by Bernier and became a serious foundation for a reassessment of man’s natural diet.

Gassendi stressed that sensory observation was the means by which people acquired knowledge, and this Epicurean methodology underpinned the early Enlightenment’s emphasis on empirical observation. The similarity to Locke’s philosophical mantra has led many to suggest that Locke was deeply indebted to Gassendi, an assumption backed up by the fact that Locke spent hours in conversation with Bernier and owned a copy of the Abrégé.22 In the hands of Gassendi, Bernier and the members of the Royal Society in London, the vegetarian debate was shifted into this new empirical arena.

Bernier’s observations in India and his trials on his patients provided a new set of empirical data that appeared to substantiate Gassendi’s anatomical argument. Decades later, when John Wallis read about Tyson’s recent meticulous dissection of animals, he remembered Gassendi’s vegetarian treatise, and realised that here was yet another set of data that might shed light on the question. While Gassendi had focused on the morphology of the teeth, Tyson and Wallis extended the enquiry to the shape and function of animals’ guts. Wallis pointed out that herbivores tended to have intestines designed for slow digestion with a large colon and ‘caecum’ (a pouch between the small and large intestine). Carnivores, on the other hand, had little or no colon and the caecum was reduced to a small appendix or was completely absent, indicating a rapid digestion of food.

Wallis agreed that the human caecum was small and shrivelled but this was not necessarily natural, since the human foetus had a much larger, healthy caecum. Overall, the human intestines, Wallis and Tyson agreed, fell in line with the herbivores. So did those of the monkeys, baboons, apes and, as Tyson had shown, the Homo sylvestris whose guts were proportionally exactly the same dimensions as man’s.23 On the basis of the evidence, Tyson grudgingly – but decisively – agreed with Gassendi, ‘that Nature never designed [Man] to live on Flesh; but, that the Wantonness of his Appetite, and a depraved Custom, has inured him to it.’ This was exactly the claim of the radical vegetarians. If Thomas Tryon had been in the habit of reading scientific papers he might have been enthralled to find his religious and moral theories so clearly backed up by the latest scientific research. But Tyson and Wallis were not ready to part with their ‘depraved’ meat dinners. Despite their recognition of the very strong evidence, they refused to endorse a return to the natural diet. ‘I am not fond of advancing a New Hypothesis, contrary to the common sense of mankind,’ said Wallis. ‘And I should not have ventured so far, if Gassendus had not first broken the ice.’24 Wallis couldn’t face relinquishing meat, and instead he claimed that because meat-eating was universally practised it must be natural after all. Rather than accept the unpalatable conclusion that God intended he should be herbivorous, Tyson scuppered the entire basis of comparative anatomy and pointed out exceptions to the rule, such as the hedgehog and the opossum, the latter of which he had recently shown to have the gut of a herbivore but was carnivorous.25

Paradoxically, the papers published by Wallis and Tyson presented evidence in favour of the herbivorous nature of man, but argued for the opposite. It was therefore used by both vegetarians and anti-vegetarians to support both sides of the debate for decades to come. John Evelyn read and marked up his copy of these papers, finding it most surprising, for example, that both Wallis and Tyson made the blunder of asserting that there were no vegetarian people on earth.26 The eighteenth-century medical lecturers Boerhaave and Haller cited the articles to support their view that man was naturally omnivorous;27 John Arbuthnot claimed that they proved man was ‘a carnivorous Animal’;28 while the Italian vegetarian Antonio Cocchi, on the other hand, used the evidence to argue that the human gut showed we were supposed to be herbivores.29

When naturalists started to divide all creatures on earth into a taxonomical system, Gassendi’s anatomical arguments remained profoundly influential.30 In his seminal Historia Plantarum (1686–1704), the eminent botanist John Ray (1627–1705) asserted conclusively that ‘Certainly man by nature was never made to be a carnivorous animal, nor is he armed at all for prey and rapine, with jagged and pointed teeth and crooked claws sharpened to render and tear, but with gentle hands to gather fruit and vegetables, and with teeth to chew and eat them.’ The scientific evidence had obvious moral implications and he exclaimed against the unnatural consumption of ‘the reeking flesh of butchered and slaughtered animals’.31

Ray’s taxonomical research provided the foundations for the definitive work of Carl Linnaeus, whose ‘binomial system’ of classification is still in use today. In the first edition of the Systema naturae (1735), Linnaeus placed humans and apes in the same order, Anthropomorpha (Ray’s term which Linnaeus later changed to ‘Primates’), partly on the basis that man shared the four (distinctly herbivorous) incisors of apes, monkeys and sloths.32 Even this shocking decision – which still cordoned humans off into a genus (Homo) and even a whole family of their own – was nothing like as radical as what Linnaeus privately entertained; he wrote to a zoological colleague with the challenge: ‘I demand of you, and of the whole world, that you show me a generic character … by which to distinguish between Man and Ape. I myself most assuredly know of none. I wish somebody would indicate one to me. But, if I had called man an ape, or vice-versa, I would have fallen under the ban of all ecclesiastics. It may be that as a naturalist I ought to have done so.’33 This epoch-making recognition of human proximity to animals had a lesser-known corollary: in the same year Linnaeus – a physician by training – wrote his doctoral dissertation in which he argued that a comparison of the structure of the mouth, stomach and hands of the Homo sylvestris and other mammals demonstrated that fruit was the natural food for mankind and should therefore always be prescribed to patients whose bodies had been weakened by fever.34 As royal physician and medical professor, Linnaeus kept Gassendi’s scientific vegetarian tradition alive in the Swedish university of Uppsala by encouraging his students to combine medical dietetics with anatomical analysis. For example, in 1757 the young Isaac Svensson submitted to Linnaeus a doctoral dissertation in which he argued that the most natural food for man was fruit, as was exhibited by children’s natural inclinations, the structure of the teeth, the Persians who fed on nothing but the fruit of palm trees and by the fruitarian ‘Gymnosophists, the wise men of India’.35 By this time in European universities, the Indian vegetarians had taken on the mantle of the greatest adherers to the laws of human nature. While the Western world had long ago abandoned the vegetarian laws of nature, the Indians remained a constant reminder of what they had left behind.36 These three sets of data – human anatomy, the Indian vegetarians, and the effects of the vegetable diet on ailing patients – were repeated time and time again by medical practitioners throughout the eighteenth century and beyond.