If you answered “cure,” “antidote,” or “antivenom” — you’ve obviously been reading the antonym section at www.merriam-webster.com/thesaurus/cancer.

But today’s guest Athena Aktipis says that the opposite of cancer is us: it's having a functional multicellular body that’s cooperating effectively in order to make that multicellular body function.

If, like us, you found her answer far more satisfying than the dictionary, maybe you could consider closing your dozens of merriam-webster.com tabs, and start listening to this podcast instead.

Links to learn more, summary and full transcript.

As Athena explains in her book The Cheating Cell, what we see with cancer is a breakdown in each of the foundations of cooperation that allowed multicellularity to arise:

• Cells will proliferate when they shouldn't.
• Cells won't die when they should.
• Cells won't engage in the kind of division of labour that they should.
• Cells won’t do the jobs that they're supposed to do.
• Cells will monopolise resources.
• And cells will trash the environment.

When we think about animals in the wild, or even bacteria living inside our cells, we understand that they're facing evolutionary pressures to figure out how they can replicate more; how they can get more resources; and how they can avoid predators — like lions, or antibiotics.

We don’t normally think of individual cells as acting as if they have their own interests like this. But cancer cells are actually facing similar kinds of evolutionary pressures within our bodies, with one major difference: they replicate much, much faster.

Incredibly, the opportunity for evolution by natural selection to operate just over the course of cancer progression is easily faster than all of the evolutionary time that we have had as humans since *Homo sapiens* came about.

Here’s a quote from Athena:

“So you have to shift your thinking to be like: the body is a world with all these different ecosystems in it, and the cells are existing on a time scale where, if we're going to map it onto anything like what we experience, a day is at least 10 years for them, right? So it's a very, very different way of thinking.”

You can find compelling examples of cooperation and conflict all over the universe, so Rob and Athena don’t stop with cancer. They also discuss:

• Cheating within cells themselves
• Cooperation in human societies as they exist today — and perhaps in the future, between civilisations spread across different planets or stars
• Whether it’s too out-there to think of humans as engaging in cancerous behaviour
• Why elephants get deadly cancers less often than humans, despite having way more cells
• When a cell should commit suicide
• The strategy of deliberately not treating cancer aggressively
• Superhuman cooperation

And at the end of the episode, they cover Athena’s new book Everything is Fine! How to Thrive in the Apocalypse, including:

• Staying happy while thinking about the apocalypse
• Practical steps to prepare for the apocalypse
• And whether a zombie apocalypse is already happening among Tasmanian devils

And if you’d rather see Rob and Athena’s facial expressions as they laugh and laugh while discussing cancer and the apocalypse — you can watch the video of the full interview.

Get this episode by subscribing to our podcast on the world’s most pressing problems and how to solve them: type 80,000 Hours into your podcasting app.

Producer: Keiran Harris
Audio mastering: Milo McGuire
Transcriptions: Katy Moore