The premise of Steven Pinker’s latest book Enlightenment Now (“My new favourite book of all time”: Bill Gates) is as follows. Humankind evolved in an essentially hostile world, set in an indifferent universe, and for millennia humans merely compounded these unfavourable conditions with their own special savagery and error. Yet within the last few centuries they have learned how to live long lives in safety, comfort, and good health, not just getting steadily more prosperous, but having popular access to forms of wealth (information, communications) not available even to the Croesuses and Fuggers of former times.
All this, Pinker insists, has been the consequence of those ideas and practices thought out and championed during the ‘Enlightenment’ of the late 17th and the 18th centuries: reliance on reason, the pursuit of science, humanist ideals, confidence in the possibility of progress. “The Enlightenment,” writes Pinker, “has worked – perhaps the greatest story seldom told.”  It’s “seldom told” for various reasons which he gives, the chief of them being that our brains (Pinker is a cognitive psychologist) have not had time to evolve to suit these new conditions, and remain pessimistically alert for trouble, better at fearing disaster than recognising and enjoying good fortune. Modern news media exploit and confirm this “negativity bias”. Therefore Pinker takes it on himself to tell this greatest story, and the book’s title is both a statement (‘This is what we’ve gained, thanks to the Enlightenment’) and an injunction: hold fast to it because, as he says on the last page of the book, “there is no limit to the betterments we can attain if we continue to apply knowledge to enhance human flourishing.” 
“human flourishing” – the index to the book gives some hint of the range and detail of its manifestations in Pinker’s survey: freedom, equal rights, vacuum cleaners, drowning deaths [fewer of them], literacy, cooking smoke [reduced], peace, sewerage. In keeping with Enlightenment principles of reason and science, he evidences all this good news with graphs and numbers (e.g. deaths by water down by 90% over the last 115 years). It’s an impressive record, though we may doubt whether every one of these varieties of progress really does constitute flourishing. Population, for instance: Pinker argues that the growing numbers (not just proportion) of humans enjoying such benefits should be welcomed: “Every additional long-lived, healthy, well-fed, well-off person is a sentient being capable of happiness, and the world is a better place for having more of them.”  Then, not unconnected, there’s jet travel: counted by ‘number of arrivals’, we’ve apparently flourished from a mere 0.55 billion in 1995 to 1.2 billion in 2015, with all that implies of expansion in our “awareness of our planet and species” .
And there’s the key: “our planet and species”. This is the story not just of how well we’ve done for ourselves since 1700, but of how we’ve made the planet ours. Higher numbers of well-off people (to repeat) make the world itself “a better place”. Humans, then, are the world. The speciesist assumption is everywhere. When we are invited to welcome the rise of “a moral principle – Life is sacred” , there’s no need to specify that it’s human life that’s meant. Even when we congratulate ourselves on conservation successes, it’s for saving “many beloved species”  (you see what makes them worth saving).
One glaring casualty of Enlightenment-style progress, the world’s climate, Pinker acknowledges with unreserved scientific candour, but he makes this disaster part of the great adventure, rather than the delinquency, of man: “Humanity has never faced a problem like it.”  Solving problems is what science and reason do; he keeps saying it. In this sense, then, for all its enormity, climate change is like housework and death by drowning, a project for reason and science to get their teeth into. So it’s not surprising that when Pinker asks, towards the end of his book, what should be regarded as “the proudest accomplishment of our species”, he chooses science: not that we shouldn’t be proud of “the masterworks of art, music, and literature”, but these may after all not be cosmically estimable, reliably intelligible to “any tribunal of minds”, whereas our scientific knowledge is independent and absolute . The reasoning is sound, I’m sure, and I don’t suggest that Pinker should have preferred the masterworks. I just note that he expects “our species” to look for approval to the universe, not to our real paying audience (and how they do pay!) in this world. What net good we have done to any lives but our own here on “our planet” is not a question that the book gets round to asking.
Well, Steven Pinker is a humanist. “He has been named Humanist of the Year”, says the publisher (no sniggering, please), and he defines humanism as the “goal of maximizing human flourishing.”  He does note, in the last chapter of the book, that humanism “doesn’t exclude the flourishing of animals” but he explains that “this book focuses on the welfare of humankind.” Yes, it certainly does that, and rather more: it privileges that welfare to a nearly absolute degree.
It’s true that the other animal species have been given a more spacious attention in Pinker’s earlier book The Better Angels of Our Nature (2011). Even here, however, he speaks of human flourishing as “the only value that cannot be denied” , and in fact the account of animals which he does give goes some way to explaining why they seem to matter so little in Enlightenment Now.
The earlier book is a survey of human violence, including violence towards animals. Like its successor, it claims that we have made enormous progress (“the historical decline of violence”), and it aims to demonstrate as much with graphs and statistics, for as Pinker says in Enlightenment Now, “how can we appraise the state of the world? The answer is to count.”  But although he does indeed do plenty of counting – deaths in civil war, lynchings, domestic assault, levels of political violence, even (and fascinatingly) ‘apologies by political and religious leaders’, all of which do support his case – there’s a noticeable deficit in the statistical element when he speaks about the other animals.
The slaughtering of farm animals, for instance: figures for this form of violence are easily available and surely as telling as any of his other numbers, but they don’t appear in the book. Pinker concedes, in words only, that there has been “a stealthy creeping up of the numbers”, but he explains it as a growing preference for chicken meat, which costs more individual lives per weight of food than, for instance, beef. This explanation helps him to fit the daily world-wide massacre of animals into his general thesis, because the numbers reflect “changes in economics and taste” rather than “a backsliding of moral sensibilities or an increase in callousness” . That’s all right then, and by way of further reassurance, cruelties to farmed animals “are by no means a modern invention”, and factory farming itself “not a phenomenon of the 20th century” . The point is illustrated not with numbers (which would hardly do it) but with some gruesome and obsolete cruelties quoted from histories of food. We can take satisfaction, then, in our increased human decency, even though the total suffering caused by its deficiencies is actually going up. It’s an argument which would not, I think, be accepted anywhere else in either book.
But then can they even be called deficiencies? Meat-eating, for instance: is its opposite, vegetarianism, really such an ethical choice? Pinker argues that vegetarianism has always been a scene of mixed motives (asceticism, health, belief in the transmigration of souls); it’s a line of argument whose summation (and one sees it coming from afar) is the vegetarianism of “Hitler and many of his henchmen” . So you can feel confident that he’ll also be mentioning the fact that other animals eat each other (“nature red in tooth and claw”), which in fact he does on p.571.
So although we humans have apparently been able to half-cure our devotion to war, an achievement which Pinker very reasonably classes among “those psychological retunings … that cause violence to decline” , no such retuning is expected or even much missed in our eating habits. After all, as Pinker states with a fatalism quite opposite to his general thesis, killing animals for food is “part of the human condition” .
Very much the same technique of argument is used for vivisection. On the one hand, there has been a great improvement. Pinker describes the routine cruelties of laboratory life in the U.S.A. as recently as 1975, when he had some direct experience of it, but he is “relieved to say” that “just five years later, indifference to the welfare of animals among scientists had become unthinkable, indeed illegal.”  This is an assertion for which no statistics are provided. (N.B. The Silver Spring monkeys scandal dates from 1981-3. I won’t attempt to list the other abuses which PETA has exposed in laboratories over the years since then.) Then, again undocumented, not only are animals “now protected from being hurt, stressed, or killed in the conduct of science” by adults, but “in high school biology labs the venerable custom of dissecting pickled frogs has gone the way of inkwells and slide rules.”  If this shaky assertion is at least a welcome idea, things are even better in the U.K. Here, according to Pinker, scientists “acceded to laws banning vivisection” as long ago as the late nineteenth century . No statistics are provided, in fact no details at all, and I don’t know how they could be. (Incidentally, we’re also told that all blood-sports have been illegal in the U.K. since 2005.)
On the other hand, like meat-eating, it seems that vivisection is just one of those things (perhaps there are only the two of them) about which it can’t be said that there is “no limit to the betterments which we can attain” (the phrase from Enlightenment Now). The general proposition in both books is that humans aren’t fated to any particular status quo. With the aid of reason, science, and optimism, we can change anything for the better: “Indeed, a naïve faith in stasis has repeatedly led to prophecies of environmental doomsdays that never happened.” [EN 125] And so, for instance, we needn’t fear that the world will “run out of resources” [EN 126]; we can find others, or other ways of getting the benefits which such resources gave us: “Why should the laws of nature have allowed exactly one physically possible way of satisfying a human desire, no more and no less?” [EN 127] Why indeed, but evidently that is all they’ve allowed in the case of vivisection, for we’re told that without this particular way of doing research “medicine would be frozen at its current state, and billions of living and unborn people would suffer and die for the sake of mice.”  Violence towards other species, it seems, is the one thing that the laws of nature, including our own human nature, simply won’t allow us to abjure.
Pinker does not himself see the animal question as an exception to his argument. At any rate he presents it in such a way as to show that we have indeed improved even here, in the hardest of all tests of our moral progress, and he waves genial goodbye to it with a fittingly unconvincing assurance: “it is certain that the lives of animals will continue to improve.” 
These two big books (more than 1500 pages between them) demand respect and attention: they are mighty in scope, they’re written with wit and lucidity, and mostly they’re telling good if often disputable news. You’d have to call them ‘important’ books, influential books at least (“The most inspiring book I’ve ever read”: Bill Gates again, on Better Angels this time). That makes their rigid anthropocentrism both significant and deplorable.
There’s a chapter in Enlightenment Now titled ‘Progressophobia’, in which Pinker reviews some of the objections and objectors to the case he presents. Among these latter is the political philosopher John Gray “an avowed progressophobe” [EN 191]. Certainly Gray himself is no teller of good news, but at least he reminds us that there is more light shining in the world than that one beam of human mind which Pinker urges us to see by:
Humanism is a doctrine of salvation – the belief that humankind can take charge of its destiny … But for anyone whose hopes are not centred on their own species, the notion that human action can save themselves or the planet must be absurd … What could be more hopeless than placing the Earth in the charge of this exceptionally destructive species? It is not of becoming the planet’s wise stewards that Earth-lovers dream, but of a time when humans have ceased to matter.
Notes and References:
Quotations are from Enlightenment Now: the Case for Reason, Science, Humanism and Progress (Allen Lane, 2018) and The Better Angels of our Nature: a History of Violence and Humanity (Penguin Books, 2012, first published 2002), page numbers as given in square brackets. The testimonials from Bill Gates appear on the two covers. John Gray is quoted from Straw Dogs: Thoughts on Humans and Other Animals, Granta Books, 2003 (first published 2002), pp.16-17.
For the Silver Spring exposé, see https://www.peta.org/issues/animals-used-for-experimentation/silver-spring-monkeys/.