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