Content warning: Spoilers for Doctor Who S09E11! Also some references to animal suffering and mortality.

One of the greatest episodes of television I have ever seen is “Heaven Sent”, which is the second-to-last episode of the 9th season of Doctor Who.

I’m actually not a huge Doctor Who fan. But this episode is a banger. You don’t even need to know about Doctor Who to enjoy it, beyond knowing that the TARDIS is the Doctor’s signature intergalactic time machine. The premise is as follows (condensed from Wikipedia):

The Twelfth Doctor is teleported into a glass chamber within an empty castle in the sea. He is pursued by a cloaked veiled figure. The Doctor jumps out of a window into the sea, finding many skulls under the water. He takes advantage of the figure’s slow reaction time to explore the castle, finding several strange remnants of his predecessors, such as dry replacement clothes, a skull connected to the transportation chamber, and the word “bird” written in dust. […] the Doctor discovers a wall of Azbantium; a mineral harder than diamond, behind which he theorises the TARDIS to be. He realises that “bird” refers to “The Shepherd Boy”, a fairytale by the Brothers Grimm in which a shepherd’s boy says to an Emperor that a second of eternity will have passed when a bird chisels a diamond mountain down to nothing with its beak. […] the Doctor punches the wall while reciting the fable. The figure mortally injures the Doctor, disabling his regeneration. He crawls back to the teleportation chamber, and burns his body as a catalyst to restart the teleport, aware that a “blueprint” of himself is inside. He then falls to the ground, writes “bird” in the dust, and disintegrates, reduced to the skull which the Doctor had seen earlier. A new Doctor appears, starting the cycle anew.

I saw this episode when it first broadcast in 2015. It has stayed with me for ten years.

I often think about the Quakers in the United Kingdom and the United States, who were arguing against slavery as early as the 1600s. This was two centuries before the abolition of slavery in the United States. The Quakers initial efforts set the ground for much of the later political advocacy by key abolitionists in the UK and the US. Had the Quakers not argued against slavery, it probably would have been more difficult for the figures we know about—John Quincy Adams, William Wilberforce, Frederick Douglass, Abraham Lincoln—to bring about the end to state-sanctioned slavery in their countries. But this benefit took two hundred years to materialise (and even today we are still grappling with both modern slavery and the socio-economic legacy of state-sanctioned slavery), and the Quakers certainly had no certainty that their efforts would ever pay off. How on Earth did the Quakers remain motivated in the 1600s?

There is a very obvious analogy with the animal advocacy movement in the 21st century. Of course, there are some important differences between slavery and industrial animal agriculture, but there are also some important similarities. We have a very long journey ahead of us. This will take sustained, intelligent effort.

I have analysed animal welfare policy around the world (in fact, in every continent except for Antarctica). Trust me when I say there is no victory on the horizon. We are not on the cusp of abolishing industrial animal torture once and for all—there is no transformative animal agriculture ban or even economically competitive cultured meat product right around the corner. We are seeing meaningful progress, but every victory is hard-won and fraught, and there are powerful social and economic forces working against progress.

This is the challenge of an animal advocate in the 21st century. We are the Doctor, punching the wall of Azbantium. We can dedicate our lives to figuring the most impactful way to punch the wall, and we each get just a couple of punches. Once we break through this wall, people will stop torturing and killing our animal friends. We cannot break through this wall in our lifetime. But we have to punch it anyway to make it easier for our descendants, in centuries, to finally break through. Once one generation punches the wall a few times, that generation dies—along with trillions of farmed animals (Faunalytics reports 71 billion land animals, but this excludes farmed fish and farmed shrimp which are the most numerous groups). We have to do this with no certainty that we will ever succeed. But every punch brings progress for a few thousand or million of those animals.

You punch the Azbantium wall a few times. Then you die, along with trillions of your innocent friends. But you have to punch the wall anyway—this is perhaps the most important thing you can do with your life. This is the central mission of animal advocacy in the 21st century.