In Steven Pinker’s new book out this month, Enlightenment Now, the Harvard professor catalogs reams of data to show that the world has actually gotten much better over time, despite what you hear on the news. The book looks at increased life spans, decreased inequality, and even a 37-fold reduction in deaths from lightning bolts as cause for optimism in humanity. After more than 500 pages, it’s hard not to be convinced.

But the question remains whether Pinker’s seemingly exhaustive treatment is neglecting some entire category of negative trends, such as the experiences of nonhuman animals who share this planet with us. The human population is around seven billion today, and will perhaps be ten billion by 2050. Yet here are over 100 billion domestic animals (the vast majority of whom are in the food system) and a quadrillion wild vertebrates (with many more invertebrates).

Unfortunately, their current situation is unimaginable suffering.

Over 99% of animals raised for food in the US currently live in factory farms (over 90% globally), many of them enduring horrific conditions like intense confinement in tiny cages so small they can barely turn around. The number of these animals has vastly increased over the past century. It’s even increased over the past decade, mainly due to rising incomes and trends of Westernization in countries like China and India, though US numbers have remained fairly stable.

At the Sentience Institute, a nonprofit think tank focused on the expansion of humanity’s moral circle where I work as research director, we try to better understand the state of affairs for animals (who make up the bulk of excluded sentient beings) and how it can be improved.

Given the abundant neuroscientific and behavioral evidence of these animals’ sentience, not to mention the environmental devastation and public health harms caused by animal farming, does this issue undercut the upward trend documented by Pinker? I think the answer is yes, if we’re considering only the state of human and animal welfare today.

However, I think a better metric is human attitudes towards animals, because it’s a bigger driver of future trends. Polls on this topic are fascinating. Despite the fact that less than 1% of US consumers usually eat meat from animals from non-factory farms, a poll we ran in November suggested 47% “support a ban on slaughterhouses.” In a 2015 Gallup poll, 32% of respondents said “[a]nimals deserve the exact same rights as people to be free from harm and exploitation.”

Why the apparent gulf between values and behavior? First, misleading marketing from animal agriculture has portrayed the industry as humane and picturesque, despite numerous undercover investigations and reports showing a horrific reality. Second, we want to believe we’re good people, and we’ll go to great lengths to justify our behavior, including the creation of a psychological refuge whereby we take shelter in the mistaken belief that the animals were treated well. Finally, it’s just a much greater cost to make personal change than to support institutional change: if I go vegan, I have to sort through restaurant options to ensure my needs are met, but if the world goes vegan, then I can pick anything on the menu just like I could before.

This is good reason for optimism. With virtually every social movement—from environmentalism, children’s rights, antislavery, to feminism—we’ve seen people transcend the limitations of individual consumer choices via institutional change. Indeed, we’ve already seen companies around the world commit to cage-free eggs, despite only a tiny fraction of consumers selecting cage-free eggs when given the option at a grocery store. The most recent campaign to ban the sale of cage eggs in Massachusetts received 77.7% of the popular vote.

These consumer attitudes suggest that Pinker’s optimism about human welfare actually might apply—at least with great caution—to animal welfare.

The ethical costs of animal farming also portend its downfall. The industry exploits complex, sentient beings as resources, which is a woefully inefficient process. To process plant calories into animal calories, the animal does a lot more than just produce meat, eggs, and dairy. She grows hair, teeth, bones. She walks around. And most importantly, she has a brain with the capacity for sentient experience — no small metabolic task. This means that for every ten calories of plant-based food we feed a farmed animal, we get around one calorie of meat in return.

Humanity tends towards efficiency for better or worse, which suggests that, in the long run, we will transcend the animal, even if individuals fail to muster sufficient moral motivation. We’ll produce meat, eggs, and dairy without the costly middleman. Scientists and chefs are already working on so-called “clean meat,” real meat made without the ethical and food safety costs of animal slaughter. They do this by taking a small sample of cells from a living animal and mixing them with food, energy, and growth factors—in the same process that happens inside an animal’s body. In fact, the first products are expected to roll out to select restaurants over the next couple of years.

Of course, consumer attitudes and technological trends aren’t cause for blind optimism in the case of human or animal welfare. There’s a rocky and precarious climb ahead. My greatest fear isn’t backsliding into the Middle Ages when blatant animal cruelty like cat burning (literally burning cats in a public place for entertainment) was widely accepted. My fear is instead that our values will stagnate, leaving the smallest and strangest sentient creatures stranded outside our moral circle. What if we expand that circle to chickens, pigs, and cows, but never fish? What about artificial sentience, if humanity gains the capacity to build feeling machines?

So let’s keep climbing the mountain of progress, foothold by foothold. Let’s stop once in a while to enjoy the view—I’m glad Pinker is pushing for this in a world that does it too rarely. But let’s also occasionally pause to acknowledge and strategize for the epic task ahead of us. Let’s keep in mind not just those beings who won the metaphysical lottery by being born as Homo sapiens, but also those who lie furthest outside our moral circle. They need us the most.